PSENEN

UniProt ID: Q9NZ42
Organism: Homo sapiens
Review Status: COMPLETE
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Gene Description

PSENEN encodes PEN-2, a small multipass membrane protein and essential non-catalytic subunit of the gamma-secretase intramembrane protease complex. Together with a presenilin catalytic subunit, nicastrin, and APH1A or APH1B, PEN-2 promotes presenilin maturation/endoproteolysis, gamma-secretase complex stability and trafficking, and intramembrane cleavage of substrates including APP and Notch receptors. PEN-2 localizes primarily to endoplasmic-reticulum and cis-Golgi membranes, with evidence for cell-membrane and other membrane compartments; additional orthology-based evidence links PEN-2 to energy-stress signaling through V-ATPase/AMPK/TORC1 regulation.

Existing Annotations Review

GO Term Evidence Action Reason
GO:0007220 Notch receptor processing
IBA
GO_REF:0000033
ACCEPT
Summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through its role in complex maturation and activity.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IBA
GO_REF:0000033
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0005789 endoplasmic reticulum membrane
IEA
GO_REF:0000044
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
IEA
GO_REF:0000044
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016020 membrane
IEA
GO_REF:0000044
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0032580 Golgi cisterna membrane
IEA
GO_REF:0000044
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005515 protein binding
IPI
PMID:15322109
Both the sequence and length of the C terminus of PEN-2 are ...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:16641999
TMP21 is a presenilin complex component that modulates gamma...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:18201567
Cellular localization of Nicastrin affects amyloid beta spec...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:23685131
Ferritin light chain interacts with PEN-2 and affects γ-secr...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:30559186
Bax inhibitor 1 is a γ-secretase-independent presenilin-bind...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:32296183
A reference map of the human binary protein interactome.
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0005515 protein binding
IPI
PMID:32814053
Interactome Mapping Provides a Network of Neurodegenerative ...
MARK AS OVER ANNOTATED
Summary: The interaction evidence is compatible with PSENEN complex/substrate associations, but generic protein binding is not an informative molecular function for this gene.
Reason: Prefer gamma-secretase complex membership and endopeptidase-activator/contribution terms over broad protein-binding annotations.
GO:0016485 protein processing
IEA
GO_REF:0000107
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042149 cellular response to glucose starvation
IEA
GO_REF:0000107
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:0042734 presynaptic membrane
IEA
GO_REF:0000107
KEEP AS NON CORE
Summary: Presynaptic membrane localization is plausible for some transferred annotations but is peripheral to the main ER/Golgi/cell-membrane gamma-secretase complex localization evidence.
Reason: Retain as non-core because it may reflect a real context-specific localization without defining the primary PSENEN function.
GO:0061133 endopeptidase activator activity
IEA
GO_REF:0000107
ACCEPT
Summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase proteolytic activity, supporting an endopeptidase-activating role at the complex level.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IEA
GO_REF:0000107
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0140678 molecular function inhibitor activity
IEA
GO_REF:0000107
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:1904262 negative regulation of TORC1 signaling
IEA
GO_REF:0000107
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:0042149 cellular response to glucose starvation
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:0140678 molecular function inhibitor activity
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:1904262 negative regulation of TORC1 signaling
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: This starvation/TORC1/AMPK-related annotation represents a plausible gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function supported by the human gamma-secretase literature.
Reason: Retain as non-core because this likely reflects a gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred by orthology or automation, not the primary human PSENEN gamma-secretase function reviewed here.
GO:0005789 endoplasmic reticulum membrane
NAS
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0007220 Notch receptor processing
NAS
PMID:10206645
A presenilin-1-dependent gamma-secretase-like protease media...
ACCEPT
Summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through its role in complex maturation and activity.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0031293 membrane protein intracellular domain proteolysis
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042987 amyloid precursor protein catabolic process
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IPI
PMID:26280335
An atomic structure of human γ-secretase.
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0000139 Golgi membrane
NAS
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016485 protein processing
IMP
PMID:12522139
PEN-2 and APH-1 coordinately regulate proteolytic processing...
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0005789 endoplasmic reticulum membrane
EXP
PMID:12522139
PEN-2 and APH-1 coordinately regulate proteolytic processing...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005789 endoplasmic reticulum membrane
EXP
PMID:12639958
Membrane topology of gamma-secretase component PEN-2.
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
EXP
PMID:24941111
Pen-2 is essential for γ-secretase complex stability and tra...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016020 membrane
EXP
PMID:12198112
PEN-2 is an integral component of the gamma-secretase comple...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016485 protein processing
IMP
PMID:12660785
The role of presenilin cofactors in the gamma-secretase comp...
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0016485 protein processing
IGI
PMID:12763021
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-se...
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0019899 enzyme binding
IPI
PMID:12522139
PEN-2 and APH-1 coordinately regulate proteolytic processing...
KEEP AS NON CORE
Summary: Broad enzyme binding is plausible for a PSENEN gamma-secretase subunit but is less informative than complex membership and activator/contribution terms.
Reason: Retain as non-core because it may reflect real interaction with presenilin enzyme complexes without defining the primary PSENEN molecular role.
GO:0034205 amyloid-beta formation
IGI
PMID:12763021
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-se...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042987 amyloid precursor protein catabolic process
IMP
PMID:12660785
The role of presenilin cofactors in the gamma-secretase comp...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042987 amyloid precursor protein catabolic process
IGI
PMID:12763021
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-se...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0061133 endopeptidase activator activity
IMP
PMID:12522139
PEN-2 and APH-1 coordinately regulate proteolytic processing...
ACCEPT
Summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase proteolytic activity, supporting an endopeptidase-activating role at the complex level.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0061133 endopeptidase activator activity
IGI
PMID:12763021
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-se...
ACCEPT
Summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase proteolytic activity, supporting an endopeptidase-activating role at the complex level.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IGI
PMID:12763021
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-se...
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0010950 positive regulation of endopeptidase activity
IMP
PMID:12660785
The role of presenilin cofactors in the gamma-secretase comp...
ACCEPT
Summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase proteolytic activity, supporting an endopeptidase-activating role at the complex level.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0034205 amyloid-beta formation
IMP
PMID:12660785
The role of presenilin cofactors in the gamma-secretase comp...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0010008 endosome membrane
TAS
Reactome:R-HSA-9010096
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016020 membrane
IDA
PMID:25043039
Three-dimensional structure of human γ-secretase.
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0016020 membrane
IDA
PMID:26280335
An atomic structure of human γ-secretase.
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0034205 amyloid-beta formation
IMP
PMID:25043039
Three-dimensional structure of human γ-secretase.
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0034205 amyloid-beta formation
IMP
PMID:26280335
An atomic structure of human γ-secretase.
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042982 amyloid precursor protein metabolic process
IDA
PMID:25043039
Three-dimensional structure of human γ-secretase.
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042982 amyloid precursor protein metabolic process
IDA
PMID:26280335
An atomic structure of human γ-secretase.
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IDA
PMID:25043039
Three-dimensional structure of human γ-secretase.
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0070765 gamma-secretase complex
IDA
PMID:26280335
An atomic structure of human γ-secretase.
ACCEPT
Summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase complex with presenilin, nicastrin, and APH1.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-1251997
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-193682
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-205112
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-2220988
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-3928656
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-9013361
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-9017817
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-HSA-9839376
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-NUL-2197556
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005886 plasma membrane
TAS
Reactome:R-NUL-9604300
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005783 endoplasmic reticulum
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0005794 Golgi apparatus
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and substrate-processing compartments.
Reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, cis-Golgi, cell-membrane, and general endomembrane localization evidence.
GO:0006509 membrane protein ectodomain proteolysis
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
MODIFY
Summary: Gamma-secretase acts after ectodomain shedding and performs intramembrane cleavage; ectodomain proteolysis is not the best PSENEN process label.
Reason: Use intramembrane substrate-processing terms rather than ectodomain proteolysis for the PSENEN-containing gamma-secretase complex.
GO:0007220 Notch receptor processing
TAS
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through its role in complex maturation and activity.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0016485 protein processing
IDA
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: This captures regulated membrane-substrate processing by the PSENEN-containing gamma-secretase complex.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.
GO:0042987 amyloid precursor protein catabolic process
TAS
PMID:15274632
Purification and characterization of the human gamma-secreta...
ACCEPT
Summary: PSENEN-containing gamma-secretase participates in APP processing and amyloid-beta-related product formation.
Reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic gamma-secretase subunit that promotes presenilin maturation, complex stability, trafficking, and APP/Notch substrate processing.

Core Functions

PSENEN/PEN-2 is an essential non-catalytic gamma-secretase subunit that promotes presenilin endoproteolysis, stabilizes and traffics the assembled complex, and enables presenilin-dependent intramembrane cleavage of APP, Notch receptors, and related membrane substrates.

Supporting Evidence:
  • PMID:12198112
    a critical component of PS1/gamma-secretase and PS2/gamma-secretase complexes
  • PMID:12198112
    PEN-2 is an integral gamma-secretase complex component
  • PMID:12522139
    Down-regulation of PEN-2 expression by small interfering RNA (siRNA) abolishes the endoproteolysis of PS1
  • PMID:12660785
    PEN-2 is required for endoproteolytic processing of presenilin and conferring gamma-secretase activity to the complex
  • PMID:24941111
    Pen-2 may also stabilize the complex prior to PS1 endoproteolysis, allowing time for full assembly and proper trafficking
  • PMID:25043039
    The γ-secretase complex consists of four components: presenilin, Pen-2, Aph-1, and Nicastrin

References

Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator judgment of sequence similarity
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Automatic transfer of experimentally verified manual GO annotation data to orthologs using Ensembl Compara
A presenilin-1-dependent gamma-secretase-like protease mediates release of Notch intracellular domain.
PEN-2 is an integral component of the gamma-secretase complex required for coordinated expression of presenilin and nicastrin.
PEN-2 and APH-1 coordinately regulate proteolytic processing of presenilin 1.
Membrane topology of gamma-secretase component PEN-2.
The role of presenilin cofactors in the gamma-secretase complex.
APH1, PEN2, and Nicastrin increase Abeta levels and gamma-secretase activity.
Purification and characterization of the human gamma-secretase complex.
Both the sequence and length of the C terminus of PEN-2 are critical for intermolecular interactions and function of presenilin complexes.
TMP21 is a presenilin complex component that modulates gamma-secretase but not epsilon-secretase activity.
Cellular localization of Nicastrin affects amyloid beta species production.
Ferritin light chain interacts with PEN-2 and affects γ-secretase activity.
Pen-2 is essential for γ-secretase complex stability and trafficking but partially dispensable for endoproteolysis.
Three-dimensional structure of human γ-secretase.
An atomic structure of human γ-secretase.
Bax inhibitor 1 is a γ-secretase-independent presenilin-binding protein.
A reference map of the human binary protein interactome.
Interactome Mapping Provides a Network of Neurodegenerative Disease Proteins and Uncovers Widespread Protein Aggregation in Affected Brains.
Reactome:R-HSA-1251997
Cleavage of ERBB4m80 by gamma-scretase complex
Reactome:R-HSA-193682
gamma-secretase cleaves the p75NTR transmembrane domain
Reactome:R-HSA-205112
gamma-secretase cleaves p75NTR, releasing NRIF and TRAF6
Reactome:R-HSA-2220988
NEXT1 PEST domain mutants are cleaved to produce NICD1 PEST domain mutants
Reactome:R-HSA-3928656
gamma-secretase cleaves EPHB2
Reactome:R-HSA-9010096
Gamma-secretase cleaves APP(672-770) to APP(672-711) and APP(672-713)
Reactome:R-HSA-9013361
NEXT3 is cleaved to produce NICD3
Reactome:R-HSA-9017817
Gamma-secretase cleaves YBX1:NOTCH3
Reactome:R-HSA-9839376
TGFBR3(784-851) degradation
Reactome:R-NUL-2197556
Gamma-secretase complex cleaves mNEXT2
Reactome:R-NUL-9604300
Gamma-secretase cleaves Notch4

Suggested Questions for Experts

Q: How should GO represent PEN-2 promotion of presenilin endoproteolysis, complex stability, and trafficking without implying that PSENEN is the catalytic protease?

Suggested experts: GO molecular-function curators, gamma-secretase structure-function experts

Q: Which PSENEN energy-stress/V-ATPase/AMPK/TORC1 activities are direct human PEN-2 functions versus orthology-based or drug-response context?

Suggested experts: AMPK signaling experts, gamma-secretase complex experts

Suggested Experiments

Experiment: Use endogenous PSENEN perturbation and rescue in human neural and epithelial cells to measure presenilin endoproteolysis, complex assembly, localization, and APP/Notch substrate cleavage side by side.

Hypothesis: PEN-2 primarily controls gamma-secretase activity by promoting presenilin maturation plus complex stability and trafficking rather than by acting as an independent protease.

Type: endogenous rescue and gamma-secretase maturation assay

Experiment: Test PSENEN-dependent metformin/V-ATPase/AMPK/TORC1 signaling in human cells with gamma-secretase catalytic inhibition and presenilin-complex assembly mutants.

Hypothesis: The reported energy-stress role of PEN-2 is separable from the canonical gamma-secretase substrate-processing role.

Type: separation-of-function energy-stress signaling assay

📚 Additional Documentation

Notes

(PSENEN-notes.md)

PSENEN curation notes

2026-06-19

  • Deep-research attempt with just deep-research-falcon human PSENEN --fallback perplexity-lite timed out after 180 seconds with no generated research artifact, so this manual review uses cached UniProt, GOA, and publication evidence.
  • PSENEN encodes PEN-2, a small multipass membrane subunit of the gamma-secretase complex. UniProt and primary papers support PEN-2 as an essential non-catalytic subunit that modulates presenilin endoproteolysis, complex stability, trafficking, and gamma-secretase activity.
  • PEN-2 is a bona fide gamma-secretase complex component: Steiner et al. identify it as "a critical component of PS1/gamma-secretase and PS2/gamma-secretase complexes" and conclude that it is an integral gamma-secretase component [PMID:12198112 "a critical component of PS1/gamma-secretase and PS2/gamma-secretase complexes"; PMID:12198112 "PEN-2 is an integral gamma-secretase complex component"].
  • PEN-2 has a direct role in presenilin maturation/endoproteolysis: PEN-2 knockdown abolishes PS1 endoproteolysis and overexpression promotes PS1 fragment formation [PMID:12522139 "Down-regulation of PEN-2 expression by small interfering RNA (siRNA) abolishes the endoproteolysis of PS1"; PMID:12522139 "overexpression of PEN-2 promotes the production of PS1 fragments"].
  • Gamma-secretase activity and APP/Notch processing are core outputs. Drosophila/mammalian evidence states that PEN-2 is required for presenilin endoproteolytic processing and confers gamma-secretase activity PMID:12660785, while human structural work describes the four-component complex and APP substrate cleavage PMID:25043039.
  • PEN-2 also contributes to gamma-secretase complex stability and trafficking, not only presenilin endoproteolysis PMID:24941111.
  • The glucose-starvation/AMPK/TORC1 annotations are retained as non-core. They are not the main human PSENEN gamma-secretase function and appear in GOA via similarity/automatic transfer rather than direct cached human evidence in this review.
  • Generic protein binding and broad enzyme binding annotations are less informative than complex membership and endopeptidase-activator/contribution terms. I marked generic protein binding as over-annotated and kept enzyme binding as non-core.

2026-06-20 second-pass audit

The second-pass audit added manual reference_review metadata for PEN-2/PSENEN papers supporting integral gamma-secretase complex membership, presenilin endoproteolysis, complex stability, and purified/structural complex composition. No annotation action changes were needed: PSENEN remains curated as a small non-catalytic gamma-secretase subunit required for presenilin maturation and complex activity, while broad stress-response transfers remain non-core.

📄 View Raw YAML

id: Q9NZ42
gene_symbol: PSENEN
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: 'PSENEN encodes PEN-2, a small multipass membrane protein and essential non-catalytic
  subunit of the gamma-secretase intramembrane protease complex. Together with a presenilin
  catalytic subunit, nicastrin, and APH1A or APH1B, PEN-2 promotes presenilin maturation/endoproteolysis,
  gamma-secretase complex stability and trafficking, and intramembrane cleavage of substrates
  including APP and Notch receptors. PEN-2 localizes primarily to endoplasmic-reticulum and
  cis-Golgi membranes, with evidence for cell-membrane and other membrane compartments; additional
  orthology-based evidence links PEN-2 to energy-stress signaling through V-ATPase/AMPK/TORC1
  regulation.'
existing_annotations:
- term:
    id: GO:0007220
    label: Notch receptor processing
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through
      its role in complex maturation and activity.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0032580
    label: Golgi cisterna membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:15322109
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:16641999
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:18201567
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:23685131
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:30559186
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:32296183
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:32814053
  qualifier: enables
  review:
    summary: The interaction evidence is compatible with PSENEN complex/substrate 
      associations, but generic protein binding is not an informative molecular function
      for this gene.
    action: MARK_AS_OVER_ANNOTATED
    reason: Prefer gamma-secretase complex membership and 
      endopeptidase-activator/contribution terms over broad protein-binding annotations.
- term:
    id: GO:0016485
    label: protein processing
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042149
    label: cellular response to glucose starvation
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:0042734
    label: presynaptic membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: is_active_in
  review:
    summary: Presynaptic membrane localization is plausible for some transferred 
      annotations but is peripheral to the main ER/Golgi/cell-membrane gamma-secretase 
      complex localization evidence.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because it may reflect a real context-specific 
      localization without defining the primary PSENEN function.
- term:
    id: GO:0061133
    label: endopeptidase activator activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: enables
  review:
    summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase 
      proteolytic activity, supporting an endopeptidase-activating role at the complex 
      level.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0140678
    label: molecular function inhibitor activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: enables
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:1904262
    label: negative regulation of TORC1 signaling
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:0042149
    label: cellular response to glucose starvation
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  qualifier: involved_in
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:0140678
    label: molecular function inhibitor activity
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  qualifier: enables
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:1904262
    label: negative regulation of TORC1 signaling
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  qualifier: involved_in
  review:
    summary: This starvation/TORC1/AMPK-related annotation represents a plausible 
      gamma-secretase-independent PSENEN role, but it is not the main PEN-2 function 
      supported by the human gamma-secretase literature.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because this likely reflects a 
      gamma-secretase-independent, energy-stress/V-ATPase/AMPK-related role transferred 
      by orthology or automation, not the primary human PSENEN gamma-secretase function 
      reviewed here.
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: NAS
  original_reference_id: PMID:15274632
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0007220
    label: Notch receptor processing
  evidence_type: NAS
  original_reference_id: PMID:10206645
  qualifier: involved_in
  review:
    summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through
      its role in complex maturation and activity.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0031293
    label: membrane protein intracellular domain proteolysis
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042987
    label: amyloid precursor protein catabolic process
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IPI
  original_reference_id: PMID:26280335
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0000139
    label: Golgi membrane
  evidence_type: NAS
  original_reference_id: PMID:15274632
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016485
    label: protein processing
  evidence_type: IMP
  original_reference_id: PMID:12522139
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: EXP
  original_reference_id: PMID:12522139
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: EXP
  original_reference_id: PMID:12639958
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: EXP
  original_reference_id: PMID:24941111
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016020
    label: membrane
  evidence_type: EXP
  original_reference_id: PMID:12198112
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016485
    label: protein processing
  evidence_type: IMP
  original_reference_id: PMID:12660785
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0016485
    label: protein processing
  evidence_type: IGI
  original_reference_id: PMID:12763021
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0019899
    label: enzyme binding
  evidence_type: IPI
  original_reference_id: PMID:12522139
  qualifier: enables
  review:
    summary: Broad enzyme binding is plausible for a PSENEN gamma-secretase subunit but 
      is less informative than complex membership and activator/contribution terms.
    action: KEEP_AS_NON_CORE
    reason: Retain as non-core because it may reflect real interaction with presenilin 
      enzyme complexes without defining the primary PSENEN molecular role.
- term:
    id: GO:0034205
    label: amyloid-beta formation
  evidence_type: IGI
  original_reference_id: PMID:12763021
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042987
    label: amyloid precursor protein catabolic process
  evidence_type: IMP
  original_reference_id: PMID:12660785
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042987
    label: amyloid precursor protein catabolic process
  evidence_type: IGI
  original_reference_id: PMID:12763021
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0061133
    label: endopeptidase activator activity
  evidence_type: IMP
  original_reference_id: PMID:12522139
  qualifier: enables
  review:
    summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase 
      proteolytic activity, supporting an endopeptidase-activating role at the complex 
      level.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0061133
    label: endopeptidase activator activity
  evidence_type: IGI
  original_reference_id: PMID:12763021
  qualifier: enables
  review:
    summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase 
      proteolytic activity, supporting an endopeptidase-activating role at the complex 
      level.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IGI
  original_reference_id: PMID:12763021
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0010950
    label: positive regulation of endopeptidase activity
  evidence_type: IMP
  original_reference_id: PMID:12660785
  qualifier: involved_in
  review:
    summary: PSENEN/PEN-2 promotes presenilin endoproteolysis and gamma-secretase 
      proteolytic activity, supporting an endopeptidase-activating role at the complex 
      level.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0034205
    label: amyloid-beta formation
  evidence_type: IMP
  original_reference_id: PMID:12660785
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9010096
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IDA
  original_reference_id: PMID:25043039
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IDA
  original_reference_id: PMID:26280335
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0034205
    label: amyloid-beta formation
  evidence_type: IMP
  original_reference_id: PMID:25043039
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0034205
    label: amyloid-beta formation
  evidence_type: IMP
  original_reference_id: PMID:26280335
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042982
    label: amyloid precursor protein metabolic process
  evidence_type: IDA
  original_reference_id: PMID:25043039
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042982
    label: amyloid precursor protein metabolic process
  evidence_type: IDA
  original_reference_id: PMID:26280335
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IDA
  original_reference_id: PMID:25043039
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0070765
    label: gamma-secretase complex
  evidence_type: IDA
  original_reference_id: PMID:26280335
  qualifier: part_of
  review:
    summary: PSENEN/PEN-2 is an integral subunit of the four-component gamma-secretase 
      complex with presenilin, nicastrin, and APH1.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-1251997
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-193682
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-205112
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-2220988
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-3928656
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9013361
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9017817
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9839376
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-NUL-2197556
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005886
    label: plasma membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-NUL-9604300
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005783
    label: endoplasmic reticulum
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0005794
    label: Golgi apparatus
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: located_in
  review:
    summary: This membrane or endomembrane location is consistent with PSENEN/PEN-2 as a
      multipass gamma-secretase subunit in ER, Golgi, cell-membrane, and 
      substrate-processing compartments.
    action: ACCEPT
    reason: PSENEN/PEN-2 is a multipass membrane gamma-secretase subunit with ER, 
      cis-Golgi, cell-membrane, and general endomembrane localization evidence.
- term:
    id: GO:0006509
    label: membrane protein ectodomain proteolysis
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: Gamma-secretase acts after ectodomain shedding and performs intramembrane 
      cleavage; ectodomain proteolysis is not the best PSENEN process label.
    action: MODIFY
    proposed_replacement_terms:
    - id: GO:0031293
      label: membrane protein intracellular domain proteolysis
    - id: GO:0016485
      label: protein processing
    reason: Use intramembrane substrate-processing terms rather than ectodomain 
      proteolysis for the PSENEN-containing gamma-secretase complex.
- term:
    id: GO:0007220
    label: Notch receptor processing
  evidence_type: TAS
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: PSENEN supports gamma-secretase-dependent Notch receptor processing through
      its role in complex maturation and activity.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0016485
    label: protein processing
  evidence_type: IDA
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: This captures regulated membrane-substrate processing by the 
      PSENEN-containing gamma-secretase complex.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
- term:
    id: GO:0042987
    label: amyloid precursor protein catabolic process
  evidence_type: TAS
  original_reference_id: PMID:15274632
  qualifier: involved_in
  review:
    summary: PSENEN-containing gamma-secretase participates in APP processing and 
      amyloid-beta-related product formation.
    action: ACCEPT
    reason: The term aligns with PSENEN/PEN-2 function as an essential non-catalytic 
      gamma-secretase subunit that promotes presenilin maturation, complex stability, 
      trafficking, and APP/Notch substrate processing.
references:
- id: GO_REF:0000024
  title: Manual transfer of experimentally-verified manual GO annotation data to 
    orthologs by curator judgment of sequence similarity
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location 
    vocabulary mapping, accompanied by conservative changes to GO terms applied by 
    UniProt
  findings: []
- id: GO_REF:0000107
  title: Automatic transfer of experimentally verified manual GO annotation data to 
    orthologs using Ensembl Compara
  findings: []
- id: PMID:10206645
  title: A presenilin-1-dependent gamma-secretase-like protease mediates release of 
    Notch intracellular domain.
  findings: []
- id: PMID:12198112
  title: PEN-2 is an integral component of the gamma-secretase complex required for 
    coordinated expression of presenilin and nicastrin.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached abstract directly identifies PEN-2 as an integral 
      gamma-secretase component required for coordinated presenilin/nicastrin 
      complex expression.
- id: PMID:12522139
  title: PEN-2 and APH-1 coordinately regulate proteolytic processing of presenilin 1.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached abstract supports PEN-2 interaction with presenilin 1
      holoprotein and a direct role in presenilin endoproteolysis.
- id: PMID:12639958
  title: Membrane topology of gamma-secretase component PEN-2.
  findings: []
- id: PMID:12660785
  title: The role of presenilin cofactors in the gamma-secretase complex.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached abstract supports PEN-2 requirement for presenilin 
      endoproteolysis and conferring gamma-secretase activity to the complex.
- id: PMID:12763021
  title: APH1, PEN2, and Nicastrin increase Abeta levels and gamma-secretase activity.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached abstract includes PEN2 as a gamma-secretase complex 
      component and supports its contribution to Abeta levels and 
      gamma-secretase activity.
- id: PMID:15274632
  title: Purification and characterization of the human gamma-secretase complex.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached abstract identifies Pen-2 with presenilin, nicastrin,
      and APH-1 as components of purified active human gamma-secretase.
- id: PMID:15322109
  title: Both the sequence and length of the C terminus of PEN-2 are critical for 
    intermolecular interactions and function of presenilin complexes.
  findings: []
- id: PMID:16641999
  title: TMP21 is a presenilin complex component that modulates gamma-secretase but not 
    epsilon-secretase activity.
  findings: []
- id: PMID:18201567
  title: Cellular localization of Nicastrin affects amyloid beta species production.
  findings: []
- id: PMID:23685131
  title: Ferritin light chain interacts with PEN-2 and affects γ-secretase activity.
  findings: []
- id: PMID:24941111
  title: Pen-2 is essential for γ-secretase complex stability and trafficking but 
    partially dispensable for endoproteolysis.
  findings: []
- id: PMID:25043039
  title: Three-dimensional structure of human γ-secretase.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached full-text record supports the four-subunit human 
      gamma-secretase structural model containing Pen-2/PSENEN.
- id: PMID:26280335
  title: An atomic structure of human γ-secretase.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: Cached full-text record supports atomic gamma-secretase 
      structure and membrane-embedded complex organization including PSENEN.
- id: PMID:30559186
  title: Bax inhibitor 1 is a γ-secretase-independent presenilin-binding protein.
  findings: []
- id: PMID:32296183
  title: A reference map of the human binary protein interactome.
  findings: []
- id: PMID:32814053
  title: Interactome Mapping Provides a Network of Neurodegenerative Disease Proteins 
    and Uncovers Widespread Protein Aggregation in Affected Brains.
  findings: []
- id: Reactome:R-HSA-1251997
  title: Cleavage of ERBB4m80 by gamma-scretase complex
  findings: []
- id: Reactome:R-HSA-193682
  title: gamma-secretase cleaves the p75NTR transmembrane domain
  findings: []
- id: Reactome:R-HSA-205112
  title: gamma-secretase cleaves p75NTR, releasing NRIF and TRAF6
  findings: []
- id: Reactome:R-HSA-2220988
  title: NEXT1 PEST domain mutants are cleaved to produce NICD1 PEST domain mutants
  findings: []
- id: Reactome:R-HSA-3928656
  title: gamma-secretase cleaves EPHB2
  findings: []
- id: Reactome:R-HSA-9010096
  title: Gamma-secretase cleaves APP(672-770) to APP(672-711) and APP(672-713)
  findings: []
- id: Reactome:R-HSA-9013361
  title: NEXT3 is cleaved to produce NICD3
  findings: []
- id: Reactome:R-HSA-9017817
  title: Gamma-secretase cleaves YBX1:NOTCH3
  findings: []
- id: Reactome:R-HSA-9839376
  title: TGFBR3(784-851) degradation
  findings: []
- id: Reactome:R-NUL-2197556
  title: Gamma-secretase complex cleaves mNEXT2
  findings: []
- id: Reactome:R-NUL-9604300
  title: Gamma-secretase cleaves Notch4
  findings: []
core_functions:
- molecular_function:
    id: GO:0061133
    label: endopeptidase activator activity
  contributes_to_molecular_function:
    id: GO:0042500
    label: aspartic endopeptidase activity, intramembrane cleaving
  description: PSENEN/PEN-2 is an essential non-catalytic gamma-secretase subunit that 
    promotes presenilin endoproteolysis, stabilizes and traffics the assembled complex, 
    and enables presenilin-dependent intramembrane cleavage of APP, Notch receptors, and
    related membrane substrates.
  directly_involved_in:
  - id: GO:0031293
    label: membrane protein intracellular domain proteolysis
  - id: GO:0007220
    label: Notch receptor processing
  - id: GO:0042987
    label: amyloid precursor protein catabolic process
  - id: GO:0034205
    label: amyloid-beta formation
  - id: GO:0016485
    label: protein processing
  - id: GO:0010950
    label: positive regulation of endopeptidase activity
  locations:
  - id: GO:0005789
    label: endoplasmic reticulum membrane
  - id: GO:0032580
    label: Golgi cisterna membrane
  - id: GO:0000139
    label: Golgi membrane
  - id: GO:0005886
    label: plasma membrane
  - id: GO:0010008
    label: endosome membrane
  - id: GO:0016020
    label: membrane
  in_complex:
    id: GO:0070765
    label: gamma-secretase complex
  supported_by:
  - reference_id: PMID:12198112
    supporting_text: a critical component of PS1/gamma-secretase and PS2/gamma-secretase
      complexes
  - reference_id: PMID:12198112
    supporting_text: PEN-2 is an integral gamma-secretase complex component
  - reference_id: PMID:12522139
    supporting_text: Down-regulation of PEN-2 expression by small interfering RNA 
      (siRNA) abolishes the endoproteolysis of PS1
  - reference_id: PMID:12660785
    supporting_text: PEN-2 is required for endoproteolytic processing of presenilin and 
      conferring gamma-secretase activity to the complex
  - reference_id: PMID:24941111
    supporting_text: Pen-2 may also stabilize the complex prior to PS1 endoproteolysis, 
      allowing time for full assembly and proper trafficking
  - reference_id: PMID:25043039
    supporting_text: 'The γ-secretase complex consists of four components: presenilin, Pen-2,
      Aph-1, and Nicastrin'
proposed_new_terms: []
suggested_questions:
- question: How should GO represent PEN-2 promotion of presenilin endoproteolysis, 
    complex stability, and trafficking without implying that PSENEN is the catalytic 
    protease?
  experts:
  - GO molecular-function curators
  - gamma-secretase structure-function experts
- question: Which PSENEN energy-stress/V-ATPase/AMPK/TORC1 activities are direct human 
    PEN-2 functions versus orthology-based or drug-response context?
  experts:
  - AMPK signaling experts
  - gamma-secretase complex experts
suggested_experiments:
- description: Use endogenous PSENEN perturbation and rescue in human neural and 
    epithelial cells to measure presenilin endoproteolysis, complex assembly, 
    localization, and APP/Notch substrate cleavage side by side.
  hypothesis: PEN-2 primarily controls gamma-secretase activity by promoting presenilin 
    maturation plus complex stability and trafficking rather than by acting as an 
    independent protease.
  experiment_type: endogenous rescue and gamma-secretase maturation assay
- description: Test PSENEN-dependent metformin/V-ATPase/AMPK/TORC1 signaling in human 
    cells with gamma-secretase catalytic inhibition and presenilin-complex assembly 
    mutants.
  hypothesis: The reported energy-stress role of PEN-2 is separable from the canonical 
    gamma-secretase substrate-processing role.
  experiment_type: separation-of-function energy-stress signaling assay