LMAN1

UniProt ID: P49257
Organism: Homo sapiens
Review Status: COMPLETE
πŸ“ Provide Detailed Feedback

Gene Description

LMAN1 (Protein ERGIC-53; also Gp58, MR60, lectin mannose-binding 1) is a 510-residue type I single-pass transmembrane L-type (leguminous-type) lectin of the early secretory pathway. Its luminal carbohydrate-recognition domain binds high-mannose N-glycans in a calcium-dependent manner, making it a mannose-specific lectin (identical to the myelomonocytic lectin MR60); it is not a glycosidase and has no catalytic activity. ERGIC-53 cycles between the endoplasmic reticulum, the ER-Golgi intermediate compartment (ERGIC) and the cis-Golgi, exiting the ER in COPII-coated vesicles and returning by COPI-dependent retrograde traffic via a C-terminal dilysine/diphenylalanine motif. Together with its soluble co-receptor MCFD2 it forms an oligomeric cargo receptor (the LMAN1-MCFD2 complex; full-length cryo-EM resolves a disulfide-linked homotetramer, revising older homohexamer models) that selectively captures glycoprotein cargo in the ER and transports it to the Golgi; its best characterized cargoes are coagulation factors V and VIII, and additional secretory glycoproteins (e.g. alpha-1-antitrypsin, cathepsins) have been proposed. As an abundant, rapidly cycling cargo receptor ERGIC-53 also contributes, together with Surf4 and p24 family members, to maintaining the architecture of the ERGIC and Golgi by controlling COPI recruitment. Loss-of-function mutations in LMAN1 cause autosomal recessive combined deficiency of factors V and VIII (F5F8D1).

Existing Annotations Review

GO Term Evidence Action Reason
GO:0005793 endoplasmic reticulum-Golgi intermediate compartment
IBA
GO_REF:0000033
ACCEPT
Summary: ERGIC is the defining site of action for ERGIC-53; the phylogenetic annotation matches the UniProt subcellular location and the protein's name.
Reason: Correct core compartment; ERGIC-53 is the canonical ERGIC marker and acts there as a cycling cargo receptor.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
SUBCELLULAR LOCATION: Endoplasmic reticulum-Golgi intermediate
GO:0000139 Golgi membrane
IBA
GO_REF:0000033
ACCEPT
Summary: ERGIC-53 cycles through the Golgi apparatus membrane as part of its ER-ERGIC-Golgi itinerary; consistent with the UniProt Golgi apparatus membrane location.
Reason: Correct compartment within the cycling itinerary, though the ERGIC is the primary steady-state location.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Golgi apparatus membrane
GO:0005789 endoplasmic reticulum membrane
IBA
GO_REF:0000033
ACCEPT
Summary: ERGIC-53 captures cargo in the ER and exits via COPII vesicles; ER membrane is a bona fide part of its cycling itinerary.
Reason: Correct compartment; matches the UniProt ER membrane location and the cargo-capture step in the ER.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005537 D-mannose binding
IBA
GO_REF:0000033
ACCEPT
Summary: ERGIC-53/MR60 is a mannose-specific lectin; its CRD binds high-mannose N-glycans. The F5F8D1 variant W67S abolishes D-mannose binding, directly supporting this molecular function.
Reason: Core molecular function; ERGIC-53 is identical to the mannose-specific lectin MR60 and recombinant WT (but not W67S) binds D-mannose.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Mannose-specific lectin
PMID:19787799
could bind to
GO:0006888 endoplasmic reticulum to Golgi vesicle-mediated transport
IBA
GO_REF:0000033
ACCEPT
Summary: The defining biological process of ERGIC-53 is ER-to-Golgi transport of glycoprotein cargo as part of the LMAN1-MCFD2 cargo receptor.
Reason: Core biological process; well supported across the family and by direct human studies of FV/FVIII transport.
Supporting Evidence:
PMID:12717434
forms a specific cargo receptor for the ER-to-Golgi transport of selected
GO:0030134 COPII-coated ER to Golgi transport vesicle
IBA
GO_REF:0000033
ACCEPT
Summary: ERGIC-53 is packaged into COPII vesicles at ER exit sites for anterograde transport; a C-terminal motif recruits COPII coat components.
Reason: Correct; ERGIC-53 is a classic COPII cargo/cargo receptor exiting the ER in COPII vesicles.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0000139 Golgi membrane
IEA
GO_REF:0000044
ACCEPT
Summary: Electronic transfer of the Golgi apparatus membrane location from the UniProt subcellular location vocabulary; consistent with the cycling itinerary.
Reason: Correct compartment; redundant with the IBA Golgi membrane annotation.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Golgi apparatus membrane
GO:0005789 endoplasmic reticulum membrane
IEA
GO_REF:0000044
ACCEPT
Summary: Electronic transfer of the ER membrane location from the UniProt subcellular location vocabulary.
Reason: Correct compartment; redundant with the IBA ER membrane annotation.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0012505 endomembrane system
IEA
GO_REF:0000117
MARK AS OVER ANNOTATED
Summary: Generic ARBA electronic assignment to the endomembrane system; far less informative than the specific ERGIC/ER/Golgi compartments already annotated.
Reason: Overly general parent term; the specific ERGIC membrane, ER membrane and Golgi membrane annotations capture the localization precisely.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum-Golgi intermediate
GO:0016020 membrane
IEA
GO_REF:0000002
MARK AS OVER ANNOTATED
Summary: Bare "membrane" from InterPro; ERGIC-53 is a single-pass type I membrane protein, but the term is uninformative relative to the curated ER/ERGIC/Golgi membrane annotations.
Reason: Uninformative generic term; the specific compartment-membrane annotations are preferable. ER/ERGIC membrane would be the appropriate refinement.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Single-pass type I membrane protein
GO:0033116 endoplasmic reticulum-Golgi intermediate compartment membrane
IEA
GO_REF:0000044
ACCEPT
Summary: Electronic transfer of the ERGIC membrane location; this is the precise core compartment for ERGIC-53.
Reason: Correct and specific core compartment; redundant with the IDA ERGIC membrane annotation.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
SUBCELLULAR LOCATION: Endoplasmic reticulum-Golgi intermediate
GO:0005515 protein binding
IPI
PMID:16304051
Combined deficiency of factor V and factor VIII is due to mu...
KEEP AS NON CORE
Summary: IntAct capture of the LMAN1-MCFD2 interaction (UniProtKB:Q8NI22). MCFD2 is the soluble co-receptor; the bare protein binding term is uninformative even though the interaction is biologically central.
Reason: Records a real, important interaction (MCFD2) but bare GO:0005515 is uninformative; the cargo receptor complex (GO:0062137) and D-mannose binding capture the core function.
Supporting Evidence:
PMID:16304051
cargo receptor ferrying FV and FVIII from the
GO:0005515 protein binding
IPI
PMID:17805346
Sequential steps and checkpoints in the early exocytic compa...
KEEP AS NON CORE
Summary: IntAct capture of the ERGIC-53/ERp44 interaction (UniProtKB:Q9BS26); ERp44 is a thiol-mediated retention protein localized to the ERGIC partly through binding ERGIC-53.
Reason: Real interaction (ERp44) recorded, but bare protein binding is uninformative and peripheral to the lectin cargo-receptor core function.
Supporting Evidence:
PMID:17805346
interacts with ERGIC-53
GO:0005515 protein binding
IPI
PMID:17971482
Deletion of 3 residues from the C-terminus of MCFD2 affects ...
KEEP AS NON CORE
Summary: IntAct capture of the LMAN1-MCFD2 interaction (UniProtKB:Q8NI22); deletion of the MCFD2 C-terminus impairs binding to ERGIC-53 and causes F5F8D.
Reason: Real MCFD2 interaction, but bare protein binding is uninformative; the cargo receptor complex term captures it more meaningfully.
Supporting Evidence:
PMID:17971482
ERGIC-53/MCFD2 protein complex functions as transport receptor of
GO:0005515 protein binding
IPI
PMID:18287528
The cargo receptors Surf4, endoplasmic reticulum-Golgi inter...
KEEP AS NON CORE
Summary: IntAct capture of the ERGIC-53/Surf4 interaction (UniProtKB:O15260); Surf4 and ERGIC-53 are interacting cargo receptors.
Reason: Real interaction (Surf4) recorded, but bare protein binding is uninformative; the functional role (Golgi/ERGIC architecture) is captured by GO:0007030.
Supporting Evidence:
PMID:18287528
Surf4 was found to interact with
GO:0005515 protein binding
IPI
PMID:19787799
A novel missense mutation causing abnormal LMAN1 in a Japane...
KEEP AS NON CORE
Summary: IntAct capture of the LMAN1-MCFD2 interaction (UniProtKB:Q8NI22); the F5F8D1 W67S variant abolishes MCFD2 interaction (and D-mannose binding).
Reason: Real MCFD2 interaction, but bare protein binding is uninformative; this paper better supports the D-mannose binding annotation.
Supporting Evidence:
PMID:19787799
did not co-immunoprecipitate the mutant LMAN1 with MCFD2
GO:0005515 protein binding
IPI
PMID:20138881
Crystal structure of the LMAN1-CRD/MCFD2 transport receptor ...
KEEP AS NON CORE
Summary: IntAct capture from the LMAN1-CRD/MCFD2 crystal structure (UniProtKB:Q8NI22); defines the LMAN1-MCFD2 binding interface.
Reason: Real, structurally defined MCFD2 interaction, but bare protein binding is uninformative; the cargo receptor complex term captures it.
Supporting Evidence:
PMID:20138881
LMAN1 is a glycoprotein receptor, mediating transfer from the ER to the ER-Golgi
GO:0005515 protein binding
IPI
PMID:20142513
Structural basis for the cooperative interplay between the t...
KEEP AS NON CORE
Summary: IntAct capture from the ERGIC-53-CRD/MCFD2 structural study (UniProtKB:Q8NI22); MCFD2 binds a surface remote from the sugar-binding site.
Reason: Real MCFD2 interaction with structural detail, but bare protein binding is uninformative as a standalone function.
Supporting Evidence:
PMID:20142513
ERGIC-53-CRD binds MCFD2 through its molecular surface remote from the
GO:0005515 protein binding
IPI
PMID:33961781
Dual proteome-scale networks reveal cell-specific remodeling...
KEEP AS NON CORE
Summary: High-throughput BioPlex interactome capture of the LMAN1-MCFD2 interaction (UniProtKB:Q8NI22).
Reason: High-throughput interaction (MCFD2); bare protein binding is uninformative and not elevated to core.
Supporting Evidence:
PMID:33961781
cell-specific remodeling of the human
GO:0005515 protein binding
IPI
PMID:35271311
OpenCell: Endogenous tagging for the cartography of human ce...
KEEP AS NON CORE
Summary: OpenCell endogenous-tagging interactome capture of the LMAN1-MCFD2 interaction (UniProtKB:Q8NI22).
Reason: High-throughput interaction (MCFD2); bare protein binding is uninformative and not elevated to core.
Supporting Evidence:
PMID:35271311
cartography of human cellular organization
GO:0005793 endoplasmic reticulum-Golgi intermediate compartment
IEA
GO_REF:0000120
ACCEPT
Summary: Combined-method electronic assignment to the ERGIC, the core compartment for ERGIC-53.
Reason: Correct core compartment; redundant with IDA/IBA ERGIC annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum-Golgi intermediate
GO:0005794 Golgi apparatus
IEA
GO_REF:0000107
ACCEPT
Summary: Ortholog-based electronic assignment to the Golgi apparatus; consistent with the cycling itinerary through the Golgi.
Reason: Correct compartment within the cycling itinerary; ERGIC remains the primary steady-state location.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Golgi apparatus membrane
GO:0030017 sarcomere
IEA
GO_REF:0000107
MARK AS OVER ANNOTATED
Summary: Ortholog-based electronic assignment to the sarcomere; there is no biological support for ERGIC-53 acting at the sarcomere and it conflicts with its early-secretory-pathway localization.
Reason: Implausible compartment for an ER/ERGIC/Golgi cargo receptor; likely spurious electronic transfer.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Single-pass type I membrane protein
GO:0030134 COPII-coated ER to Golgi transport vesicle
IEA
GO_REF:0000107
ACCEPT
Summary: Ortholog-based electronic assignment to the COPII vesicle; ERGIC-53 is a COPII cargo receptor.
Reason: Correct; redundant with the IBA COPII vesicle annotation.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0005783 endoplasmic reticulum
IDA
GO_REF:0000052
ACCEPT
Summary: Direct immunofluorescence (HPA) evidence for ER localization, consistent with ERGIC-53 capturing cargo in the ER.
Reason: Correct compartment within the cycling itinerary; supported by direct imaging.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0006888 endoplasmic reticulum to Golgi vesicle-mediated transport
NAS
PMID:36490287
Separate roles of LMAN1 and MCFD2 in ER-to-Golgi trafficking...
ACCEPT
Summary: ComplexPortal NAS annotation; LMAN1 and MCFD2 form a complex that transports FV and FVIII from the ER to the Golgi, with MCFD2 carrying the cargo-binding role and LMAN1 acting as a shuttling carrier.
Reason: Core biological process; directly asserted by the cited functional study of the LMAN1/MCFD2-dependent FV/FVIII secretion pathway.
Supporting Evidence:
PMID:36490287
cargo binding and transport are carried out by MCFD2 and that LMAN1
PMID:36490287
transports FV and FVIII from the endoplasmic reticulum (ER) to the Golgi
GO:0033116 endoplasmic reticulum-Golgi intermediate compartment membrane
IDA
PMID:12717434
Bleeding due to disruption of a cargo-specific ER-to-Golgi t...
ACCEPT
Summary: Direct evidence (ComplexPortal) for ERGIC membrane localization; LMAN1 is a mannose-binding type 1 transmembrane protein localized to the ERGIC.
Reason: Correct, specific core compartment with direct support.
Supporting Evidence:
PMID:12717434
localized to the endoplasmic
GO:0062137 cargo receptor complex
IPI
PMID:12717434
Bleeding due to disruption of a cargo-specific ER-to-Golgi t...
ACCEPT
Summary: The LMAN1-MCFD2 complex (ComplexPortal CPX-8001) is a cargo receptor for ER-to-Golgi transport of FV/FVIII; MCFD2 is localized to the ERGIC through a Ca2+-dependent interaction with LMAN1.
Reason: Core cellular component; LMAN1 is a defining subunit of the LMAN1-MCFD2 cargo receptor complex.
Supporting Evidence:
PMID:12717434
forms a specific cargo receptor for the ER-to-Golgi transport of selected
GO:0005515 protein binding
IPI
PMID:34779586
BET1 variants establish impaired vesicular transport as a ca...
KEEP AS NON CORE
Summary: IntAct capture of the ERGIC-53/BET1 interaction (UniProtKB:O15155); ERGIC-53 was identified as a novel interaction partner of the ER-to-Golgi SNARE BET1.
Reason: Real interaction (BET1) recorded, but bare protein binding is uninformative; peripheral to the lectin cargo-receptor core function.
Supporting Evidence:
PMID:34779586
ERGIC‐53 as a novel interaction partner of BET1
GO:0046872 metal ion binding
EXP
PMID:24498414
Structural basis for disparate sugar-binding specificities i...
KEEP AS NON CORE
Summary: The CRD coordinates Ca2+, which is required for the lectin's high-mannose carbohydrate recognition; structural studies resolve Ca2+ in the sugar-binding pocket.
Reason: Ca2+ is a structural cofactor of the carbohydrate-recognition domain, supporting (not equivalent to) the core D-mannose binding function.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
ligand="Ca(2+)"
PMID:24498414
carbohydrate recognition domains (CRDs)
GO:0005515 protein binding
IPI
PMID:31142615
The E3 ubiquitin ligase MARCH2 regulates ERGIC3-dependent tr...
KEEP AS NON CORE
Summary: IntAct capture of the ERGIC-53/SERPINA1 (alpha-1-antitrypsin) interaction (UniProtKB:P01009); alpha-1-antitrypsin is a candidate secretory glycoprotein cargo.
Reason: Real interaction (SERPINA1) recorded; bare protein binding is uninformative, though it hints at a broader cargo repertoire.
Supporting Evidence:
PMID:31142615
Ξ±1-antitrypsin and haptoglobin specifically bind to ERGIC3
GO:0005783 endoplasmic reticulum
IDA
PMID:19401338
Role of syntaxin 18 in the organization of endoplasmic retic...
ACCEPT
Summary: Direct evidence for ER localization from a study of ER subdomain organization (syntaxin 18), consistent with ERGIC-53's cycling itinerary.
Reason: Correct compartment within the cycling itinerary; supported by direct imaging.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0031012 extracellular matrix
HDA
PMID:28675934
Characterization of the Extracellular Matrix of Normal and D...
MARK AS OVER ANNOTATED
Summary: High-throughput ECM proteomics detection; ERGIC-53 is an intracellular early-secretory-pathway membrane protein and not a genuine ECM component.
Reason: Proteomic over-detection inconsistent with the established ER/ERGIC/Golgi localization; not a true ECM protein.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum-Golgi intermediate
GO:0031012 extracellular matrix
HDA
PMID:25037231
Extracellular matrix signatures of human primary metastatic ...
MARK AS OVER ANNOTATED
Summary: High-throughput ECM proteomics detection in colon cancer tissue; not a genuine ECM localization for this intracellular cargo receptor.
Reason: Proteomic over-detection inconsistent with the established intracellular localization.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum-Golgi intermediate
GO:1903748 negative regulation of protein localization to mitochondrion
HMP
PMID:24270810
High-content genome-wide RNAi screens identify regulators of...
KEEP AS NON CORE
Summary: LMAN1 was a hit in a genome-wide RNAi screen for regulators of parkin translocation to damaged mitochondria; a high-throughput phenotype far removed from its characterized cargo-receptor function.
Reason: High-throughput screen hit only; peripheral and not mechanistically connected to the core ER-to-Golgi lectin function. Retained but not elevated.
Supporting Evidence:
PMID:24270810
regulators that have an impact on parkin
GO:0005793 endoplasmic reticulum-Golgi intermediate compartment
IDA
PMID:21525244
C4orf41 and TTC-15 are mammalian TRAPP components with a rol...
ACCEPT
Summary: Direct evidence for ERGIC localization from a study of mammalian TRAPP components in early ER-to-Golgi trafficking.
Reason: Correct core compartment with direct support.
Supporting Evidence:
PMID:21525244
ER-to-Golgi trafficking at a very early stage
GO:0005515 protein binding
IPI
PMID:22337587
Protein interaction profiling of the p97 adaptor UBXD1 point...
KEEP AS NON CORE
Summary: IPI capture of ERGIC-53 interactions with RAB3GAP1/RAB3GAP2 (Q15042/Q9H2M9) and UBXN6 (Q9BZV1) via its C-terminal cytoplasmic tail; the p97-UBXD1 complex modulates ERGIC-53 trafficking.
Reason: Real interactions (RAB3GAP1/2, UBXN6) recorded, but bare protein binding is uninformative; these modulate ERGIC-53 trafficking and are peripheral to the lectin core function.
Supporting Evidence:
PMID:22337587
Rab3GAP1/2 complex involved in the fusion of vesicles
GO:0033116 endoplasmic reticulum-Golgi intermediate compartment membrane
TAS
Reactome:R-HSA-5694446
ACCEPT
Summary: Reactome curation of ERGIC membrane localization in the COPII transport pathway.
Reason: Correct core compartment; redundant with experimental ERGIC annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
SUBCELLULAR LOCATION: Endoplasmic reticulum-Golgi intermediate
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-203973
ACCEPT
Summary: Reactome curation of ER membrane localization during vesicle budding.
Reason: Correct compartment; redundant with curated ER membrane annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-204008
ACCEPT
Summary: Reactome curation of ER membrane localization during COPII coat recruitment.
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-5694417
ACCEPT
Summary: Reactome curation of ER membrane localization during COPII inner-coat assembly.
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-5694428
ACCEPT
Summary: Reactome curation (LMAN family proteins bind glycosylated cargo) placing ERGIC-53 at the ER membrane.
Reason: Correct compartment; this reaction directly reflects the lectin cargo-binding role.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-5694431
ACCEPT
Summary: Reactome curation (hexameric LMAN1:MCFD2 bind glycosylated Factor V and VIII precursors) placing ERGIC-53 at the ER membrane.
Reason: Correct compartment; this reaction directly reflects the FV/FVIII cargo-receptor role.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-5694522
ACCEPT
Summary: Reactome curation of ER membrane localization during inner coat assembly and cargo binding.
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005789 endoplasmic reticulum membrane
TAS
Reactome:R-HSA-5694527
ACCEPT
Summary: Reactome curation of ER membrane localization during COPII budding (loss of SAR1B GTPase).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0005515 protein binding
IPI
PMID:24806965
TMEM115 is an integral membrane protein of the Golgi complex...
KEEP AS NON CORE
Summary: IPI capture of the ERGIC-53/TMEM115 interaction (UniProtKB:Q12893); TMEM115 is a Golgi protein involved in retrograde transport.
Reason: Real interaction (TMEM115) recorded, but bare protein binding is uninformative and peripheral to the lectin core function.
Supporting Evidence:
PMID:24806965
interacts with the COG complex
GO:0016020 membrane
HDA
PMID:19946888
Defining the membrane proteome of NK cells.
MARK AS OVER ANNOTATED
Summary: High-throughput NK-cell membrane proteome detection; bare "membrane" is uninformative relative to the curated ER/ERGIC/Golgi membrane annotations.
Reason: Uninformative generic term from a proteomics survey; superseded by specific compartment-membrane annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Single-pass type I membrane protein
GO:0070062 extracellular exosome
HDA
PMID:19199708
Proteomic analysis of human parotid gland exosomes by multid...
MARK AS OVER ANNOTATED
Summary: High-throughput exosome proteomics detection (parotid gland exosomes); not a site of action for this early-secretory-pathway cargo receptor.
Reason: Proteomic over-detection; not biologically meaningful for ERGIC-53 function.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum-Golgi intermediate
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-203973
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane during vesicle budding.
Reason: Correct compartment for a COPII cargo receptor; redundant with COPII vesicle annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-5694409
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane (nucleotide exchange on RAB1).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-5694418
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane (RAB1 tethering).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-5694439
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane (COPII binds TRAPPCII and RAB1).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-5694441
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane (CSNK1D phosphorylates SEC23).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-5694446
ACCEPT
Summary: Reactome curation placing ERGIC-53 in the ER-to-Golgi transport vesicle membrane (v-SNARE binding on tethered vesicle).
Reason: Correct compartment; redundant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0012507 ER to Golgi transport vesicle membrane
TAS
Reactome:R-HSA-947991
ACCEPT
Summary: Reactome curation (Transport of glycoproteins with Man8/Man9 N-glycans to the Golgi) placing ERGIC-53 in the transport vesicle membrane; directly reflects its high-mannose lectin cargo function.
Reason: Correct compartment; this reaction directly reflects the high-mannose-glycoprotein transport role of ERGIC-53.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
proper recognition of COPII coat components
GO:0007030 Golgi organization
IMP
PMID:18287528
The cargo receptors Surf4, endoplasmic reticulum-Golgi inter...
KEEP AS NON CORE
Summary: Silencing Surf4 together with ERGIC-53 reduces ERGIC clusters and fragments the Golgi by impairing COPI recruitment; cargo receptors including ERGIC-53 are required to maintain ERGIC/Golgi architecture.
Reason: Experimentally supported (IMP), but this is an emergent structural role of an abundant cycling cargo receptor rather than its primary, defining cargo-transport function. Retained as a valid non-core process.
Supporting Evidence:
PMID:18287528
cargo receptors are essential for maintaining the architecture of ERGIC and Golgi by controlling COP I recruitment
GO:0034498 early endosome to Golgi transport
IMP NOT
PMID:18287528
The cargo receptors Surf4, endoplasmic reticulum-Golgi inter...
ACCEPT
Summary: ERGIC-53 functions in the ER-ERGIC-Golgi early secretory pathway and COPI-dependent retrograde recycling; the study shows its role is in maintaining ERGIC/Golgi architecture via COPI, with no role in early endosome to Golgi transport. The NOT qualifier correctly records that ERGIC-53 does NOT act in this endosomal pathway.
Reason: The negation is appropriate because ERGIC-53 operates in ER/ERGIC/Golgi cargo transport and COPI retrograde traffic rather than in endosome-to-Golgi transport.
Supporting Evidence:
PMID:18287528
cargo receptors are essential for maintaining the architecture of ERGIC and Golgi by controlling COP I recruitment
GO:0005793 endoplasmic reticulum-Golgi intermediate compartment
IDA
PMID:15308636
Proteomics of endoplasmic reticulum-Golgi intermediate compa...
ACCEPT
Summary: ERGIC proteomics enriched ERGIC-53 ~110-fold in purified ERGIC membranes, providing direct biochemical evidence for ERGIC localization.
Reason: Correct core compartment with direct biochemical support.
Supporting Evidence:
PMID:15308636
enriched 110-fold over the homogenate for ERGIC-53
GO:0005515 protein binding
IPI
PMID:9774442
Molecular cloning of the oncofetal isoform of the human panc...
KEEP AS NON CORE
Summary: IPI capture of an interaction with the oncofetal bile salt-dependent lipase (UniProtKB:O75612) from a cloning study; a candidate glycoprotein cargo/partner.
Reason: Real interaction recorded, but bare protein binding is uninformative and the partner is peripheral to the established function.
Supporting Evidence:
PMID:9774442
oncofetal isoform of the human pancreatic bile
GO:0005537 D-mannose binding
TAS
PMID:7876089
ERGIC-53, a membrane protein of the endoplasmic reticulum-Go...
ACCEPT
Summary: ERGIC-53 is identical to MR60, an intracellular mannose-specific lectin; the TAS annotation records the foundational identification of its D-mannose binding activity. (PMID:7876089 not cached; supported via the UniProt record documenting ERGIC-53 = MR60.)
Reason: Core molecular function; ERGIC-53/MR60 is a mannose-specific lectin, corroborated by the W67S loss-of-D-mannose-binding variant.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
is identical to MR60, an intracellular mannose-
GO:0000139 Golgi membrane
TAS
PMID:7876089
ERGIC-53, a membrane protein of the endoplasmic reticulum-Go...
ACCEPT
Summary: TAS annotation of Golgi membrane localization for ERGIC-53; consistent with its cycling itinerary through the Golgi. (PMID:7876089 not cached; supported via the UniProt record.)
Reason: Correct compartment within the cycling itinerary; redundant with curated Golgi membrane annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Golgi apparatus membrane
GO:0005789 endoplasmic reticulum membrane
TAS
PMID:7876089
ERGIC-53, a membrane protein of the endoplasmic reticulum-Go...
ACCEPT
Summary: TAS annotation of ER membrane localization for ERGIC-53. (PMID:7876089 not cached; supported via the UniProt record documenting the ER membrane location.)
Reason: Correct compartment; redundant with curated ER membrane annotations.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Endoplasmic reticulum
GO:0006457 protein folding
TAS
PMID:9546392
Mutations in the ER-Golgi intermediate compartment protein E...
KEEP AS NON CORE
Summary: The original F5F8D paper proposed ERGIC-53 may function as a "molecular chaperone" for ER-to-Golgi transport of a subset of secreted proteins. ERGIC-53 is a transport receptor, not a folding enzyme; the protein folding term reflects the historical chaperone framing of its transport role.
Reason: ERGIC-53 is a cargo receptor/lectin, not a folding catalyst; protein folding is at best an indirect, downstream consequence of efficient cargo transport. Retained as non-core.
Supporting Evidence:
PMID:9546392
ERGIC-53 may function as a molecular
GO:0006888 endoplasmic reticulum to Golgi vesicle-mediated transport
TAS
PMID:9546392
Mutations in the ER-Golgi intermediate compartment protein E...
ACCEPT
Summary: The foundational F5F8D paper implicates ERGIC-53 in ER-to-Golgi transport of a specific subset of secreted proteins including FV and FVIII.
Reason: Core biological process with strong genetic/biochemical support.
Supporting Evidence:
PMID:9546392
transport from ER to Golgi of a specific subset of secreted proteins
GO:0007596 blood coagulation
TAS
PMID:9546392
Mutations in the ER-Golgi intermediate compartment protein E...
KEEP AS NON CORE
Summary: LMAN1 mutations cause combined deficiency of coagulation factors V and VIII; blood coagulation is a physiological consequence of its role in secreting FV/FVIII, not a direct molecular activity of ERGIC-53.
Reason: Downstream physiological process resulting from cargo transport of FV/FVIII; ERGIC-53 itself has no coagulation activity. Retained as non-core.
Supporting Evidence:
PMID:9546392
combined deficiency of coagulation factors V and VIII
GO:0016020 membrane
TAS
PMID:7876089
ERGIC-53, a membrane protein of the endoplasmic reticulum-Go...
MARK AS OVER ANNOTATED
Summary: Legacy TAS "membrane" annotation; bare term is uninformative relative to the curated ER/ERGIC/Golgi membrane annotations. (PMID:7876089 not cached; supported via the UniProt record.)
Reason: Uninformative generic term; superseded by specific compartment-membrane annotations. ER/ERGIC membrane is the appropriate refinement.
Supporting Evidence:
file:human/LMAN1/LMAN1-uniprot.txt
Single-pass type I membrane protein

Core Functions

Mannose-specific L-type lectin whose luminal carbohydrate-recognition domain binds high-mannose N-glycans of glycoprotein cargo in a calcium-dependent manner.

Supporting Evidence:
  • file:human/LMAN1/LMAN1-uniprot.txt
    Mannose-specific lectin
  • PMID:24498414
    function as cargo receptors for trafficking certain N-linked glycoproteins

Subunit of the LMAN1-MCFD2 cargo receptor complex that captures glycoprotein cargo (notably coagulation factors V and VIII) in the ER and transports it via COPII vesicles to the Golgi, cycling back through COPI-dependent retrograde traffic.

Supporting Evidence:
  • PMID:12717434
    forms a specific cargo receptor for the ER-to-Golgi transport of selected
  • PMID:36490287
    transports FV and FVIII from the endoplasmic reticulum (ER) to the Golgi

References

Loading supporting content…

Download this section (compressed HTML)

Suggested Questions for Experts

Q: Given that LMAN1 N-glycan binding is dispensable for FV/FVIII transport (MCFD2 carries cargo binding), what is the full repertoire of cargoes that depend on LMAN1's own lectin activity versus those routed primarily through MCFD2?

Q: Beyond FV/FVIII, which endogenous high-mannose glycoproteins (e.g. cathepsins, alpha-1-antitrypsin) are bona fide LMAN1 cargoes in vivo?

Suggested Experiments

Experiment: Compare FV/FVIII and broader secretome trafficking in LMAN1-null cells reconstituted with wild-type LMAN1 versus the carbohydrate-binding-dead and W67S variants to separate the lectin-dependent from MCFD2-shuttling contributions.

Experiment: Perform proximity labeling (BioID/APEX) from endogenously tagged LMAN1 across cell types to define the cargo and machinery interactome and test the proposed cargoes (SERPINA1, cathepsins) as genuine clients.

Deep Research

Falcon

(LMAN1-deep-research-falcon.md)

Loading supporting content…

Download this section (compressed HTML)

πŸ“š Additional Documentation

Notes

(LMAN1-notes.md)

Loading supporting content…

Download this section (compressed HTML)

Pn Notes

(LMAN1-pn-notes.md)

Loading supporting content…

Download this section (compressed HTML)

πŸ“„ View Raw YAML

Loading supporting content…

Download this section (compressed HTML)