ABCB9 (TAPL, transporter associated with antigen processing-like) is a half-size ATP-binding cassette transporter of the ABCB subfamily that assembles as a homodimer in the limiting membrane of lysosomes and late endosomes. Each subunit has an N-terminal four-helix TMD0 domain, a six-helix core transmembrane domain and a cytosolic nucleotide-binding domain. The core dimer uses ATP hydrolysis to translocate a broad range of peptides (about 6 to 59 residues) from the cytosol into the lysosomal lumen, where they can be degraded. TMD0 carries the lysosomal targeting information and binds LAMP-1 and LAMP-2, which stabilize the transporter; it also binds YIF1B, which assists exit from the ER. ABCB9 is broadly expressed, with high levels in testis (Sertoli cells), and is induced when monocytes differentiate into dendritic cells and macrophages. Unlike TAP1/TAP2 it does not supply peptides for MHC class I loading in the ER.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0002474 antigen processing and presentation of peptide antigen via MHC class I | IDA NOT PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: NOT annotation. ABCB9 cannot replace TAP to load peptides onto MHC class I in the ER. Reason: The cited study shows that TAPL does not restore MHC class I surface expression in TAP-deficient cells. That supports the negated claim. A possible lysosomal role in cross-presentation is still speculative and does not contradict this NOT annotation. Supporting Evidence: PMID:17977821 TAPL does not, however, restore MHC class I surface expression in TAP-deficient cells |
| GO:0005515 protein binding | IPI PMID:21194361 The lysosomal polypeptide transporter TAPL: more than a hous... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:21194361 The lysosomal polypeptide transporter TAPL: more than a hous... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:21194361 The lysosomal polypeptide transporter TAPL: more than a hous... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005515 protein binding | IPI PMID:30877195 Lysosomal targeting of the ABC transporter TAPL is determine... | REMOVE | Summary: Generic protein binding (LAMP-1, LAMP-2, YIF1B and their orthologs) through the TMD0 domain. Reason: The protein-binding policy treats bare GO:0005515 as uninformative. The interactions with LAMP-1/LAMP-2 (which stabilize TAPL in the lysosomal limiting membrane) and with YIF1B (which assists ER-to-Golgi trafficking) are real. However, no specific molecular-function term describes them better, and the interaction alone gives no evidence for one. Removing the rows does not dispute that the interactions happen. Supporting Evidence: PMID:22641697 The interaction interface with LAMP was mapped to the four-transmembrane helices constituting the N-terminal domain of TAPL (TMD0). PMID:30877195 An interactome analysis revealed that Yip1-interacting factor homolog B membrane-trafficking protein (YIF1B) interacts with TAPL. |
| GO:0005524 ATP binding | IDA PMID:15863492 Selective and ATP-dependent translocation of peptides by the... | ACCEPT | Summary: ATP binding by the nucleotide-binding domain. Reason: ABCB9 has a canonical ABC nucleotide-binding domain. Purified TAPL binds ATP-agarose, and its transport needs ATP hydrolysis. ATP binding is part of how the transporter works. Supporting Evidence: PMID:18175933 Solubilized TAPL bound ATP-agarose and adenosine 5'-diphosphate (ADP)-agarose but not adenosine 5'-monophosphate (AMP)-agarose. PMID:15863492 Different nucleotides bind and energize the transport with a slight predilection for purine bases. |
| GO:0005524 ATP binding | IEA GO_REF:0000002 | ACCEPT | Summary: ATP binding by the nucleotide-binding domain. Reason: ABCB9 has a canonical ABC nucleotide-binding domain. Purified TAPL binds ATP-agarose, and its transport needs ATP hydrolysis. ATP binding is part of how the transporter works. Supporting Evidence: PMID:18175933 Solubilized TAPL bound ATP-agarose and adenosine 5'-diphosphate (ADP)-agarose but not adenosine 5'-monophosphate (AMP)-agarose. PMID:15863492 Different nucleotides bind and energize the transport with a slight predilection for purine bases. |
| GO:0005764 lysosome | IDA PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | MODIFY | Summary: Lysosomal localization. The protein is an integral component of the lysosomal limiting membrane. Reason: The localization is correct, but ABCB9 is a multi-pass membrane protein of the lysosomal limiting membrane, not a luminal lysosomal protein. Lysosomal membrane (GO:0005765), which the gene already carries with many experimental rows, is the more specific supported term. Proposed replacements: lysosomal membrane Supporting Evidence: PMID:22641697 LAMP proteins retain TAPL on the limiting membrane of endosomes and prevent its sorting to intraluminal vesicles |
| GO:0005764 lysosome | IDA PMID:30877195 Lysosomal targeting of the ABC transporter TAPL is determine... | MODIFY | Summary: Lysosomal localization. The protein is an integral component of the lysosomal limiting membrane. Reason: The localization is correct, but ABCB9 is a multi-pass membrane protein of the lysosomal limiting membrane, not a luminal lysosomal protein. Lysosomal membrane (GO:0005765), which the gene already carries with many experimental rows, is the more specific supported term. Proposed replacements: lysosomal membrane Supporting Evidence: PMID:22641697 LAMP proteins retain TAPL on the limiting membrane of endosomes and prevent its sorting to intraluminal vesicles |
| GO:0005765 lysosomal membrane | EXP PMID:15577206 Membrane localization of transporter associated with antigen... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | EXP PMID:18175933 Biochemical characterization of transporter associated with ... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | EXP PMID:20377823 Tuning the cellular trafficking of the lysosomal peptide tra... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | EXP PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | EXP PMID:30877195 Lysosomal targeting of the ABC transporter TAPL is determine... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | HDA PMID:17897319 Integral and associated lysosomal membrane proteins. | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IDA PMID:10748049 Characterization of ABCB9, an ATP binding cassette protein a... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IDA PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IDA PMID:18952056 Functional dissection of transmembrane domains of human TAP-... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IDA PMID:21194361 The lysosomal polypeptide transporter TAPL: more than a hous... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IDA PMID:21212514 Transporter associated with antigen processing-like (ABCB9) ... | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | IEA GO_REF:0000120 | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005765 lysosomal membrane | TAS Reactome:R-HSA-5223317 | ACCEPT | Summary: Lysosomal membrane is the established steady-state location of ABCB9. Reason: Several independent lines of evidence place ABCB9 in the lysosomal limiting membrane. It colocalizes with LAMP1/LAMP2 and LysoTracker, it cofractionates with lysosomal markers, it appears in the proteome of placental lysosomal membranes, and transport assays on isolated lysosomes show its activity there. TMD0 carries the lysosomal sorting signal. The protein does not reside at the plasma membrane; only the core domain without TMD0 is diverted to the cell surface. Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. PMID:17977821 TAPL was detected in the lysosomal compartment co-localizing with the lysosome-associated membrane protein LAMP-2 PMID:21212514 TAPL-GFP was co-sedimented with lysosomal marker cathepsin D on Percoll density gradient centrifugation. PMID:20377823 in contrast to the full-length transporter, the core translocation complex is targeted preferentially to the plasma membrane |
| GO:0005769 early endosome | IDA NOT PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: NOT early endosome. ABCB9 is not resident in early endosomes at steady state. Reason: Quantitative immunofluorescence and subcellular fractionation placed TAPL in the LAMP-2-positive lysosomal compartment. A later RUSH trafficking study showed that newly made TAPL passes through the Golgi to lysosomes by a direct route, so any time in early endosomes is transient. This supports the negated steady-state claim. Supporting Evidence: PMID:17977821 by using quantitative immunofluorescence and subcellular fractionation, TAPL was detected in the lysosomal compartment PMID:30877195 we demonstrate that TAPL takes the direct route to lysosomes |
| GO:0005783 endoplasmic reticulum | IDA NOT PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: NOT endoplasmic reticulum. ABCB9 does not reside in the ER at steady state. Reason: Endogenous TAPL in dendritic cells and macrophages is lysosomal and does not reconstitute ER peptide loading. The ER is only a biosynthetic transit compartment; TAPL is retained there only when TMD0 charged residues are mutated. Supporting Evidence: PMID:17977821 TAPL alone or in combination with single TAP subunits does not form a functional transport complex required for peptide loading of MHC I in the endoplasmic reticulum PMID:30877195 Substitutions of these residues retained TAPL in the endoplasmic reticulum (ER) or Golgi. |
| GO:0005789 endoplasmic reticulum membrane | IDA PMID:11011155 A half-type ABC transporter TAPL is highly conserved between... | MARK AS OVER ANNOTATED | Summary: ER membrane localization reported from early transient overexpression of TAPL-GFP in COS-1 and other cells. Reason: The early GFP-fusion overexpression studies saw PDI/ER-marker colocalization. Later work with endogenous protein, stable expression and fractionation established that steady-state ABCB9 is in the lysosomal membrane, and that ER residence is either transient biosynthetic transit or a result of overexpression or misfolding. A curated NOT ER annotation (PMID:17977821) also exists. The ER membrane is therefore not a functional location of ABCB9. Supporting Evidence: PMID:11011155 The TAPL-GFP fusion protein transiently expressed in Cos-1 cells was co-localized with PDI, suggesting that TAPL is inserted into endoplasmic reticulum membrane. PMID:21212514 These results indicated that TAPL is a lysosomal ABC transporter but not a mitochondrial one. PMID:30877195 we demonstrate that TAPL takes the direct route to lysosomes |
| GO:0005789 endoplasmic reticulum membrane | IDA PMID:1101155 [Phenotype Pi and alpha 1 antitrypsin deficiency in types A ... | MARK AS OVER ANNOTATED | Summary: ER membrane IDA attributed to PMID:1101155, which is a 1975 paper on alpha-1-antitrypsin in chronic obstructive lung disease. Reason: The cited PMID is clearly a mis-keyed reference. The cached abstract is about Pi phenotype and alpha-1-antitrypsin in COPD patients and does not mention TAPL. The intended paper is almost certainly PMID:11011155 (Kobayashi et al. 2000, TAPL-GFP colocalized with PDI), one digit longer. The claim itself is given the same action as the other ER membrane rows, over-annotation, because steady-state ABCB9 is lysosomal. Supporting Evidence: PMID:1101155 The authors studied 79 patients with chronic obstructive lung disease. PMID:11011155 The TAPL-GFP fusion protein transiently expressed in Cos-1 cells was co-localized with PDI |
| GO:0005789 endoplasmic reticulum membrane | IDA PMID:15577206 Membrane localization of transporter associated with antigen... | MARK AS OVER ANNOTATED | Summary: ER membrane localization reported from early transient overexpression of TAPL-GFP in COS-1 and other cells. Reason: The early GFP-fusion overexpression studies saw PDI/ER-marker colocalization. Later work with endogenous protein, stable expression and fractionation established that steady-state ABCB9 is in the lysosomal membrane, and that ER residence is either transient biosynthetic transit or a result of overexpression or misfolding. A curated NOT ER annotation (PMID:17977821) also exists. The ER membrane is therefore not a functional location of ABCB9. Supporting Evidence: PMID:11011155 The TAPL-GFP fusion protein transiently expressed in Cos-1 cells was co-localized with PDI, suggesting that TAPL is inserted into endoplasmic reticulum membrane. PMID:21212514 These results indicated that TAPL is a lysosomal ABC transporter but not a mitochondrial one. PMID:30877195 we demonstrate that TAPL takes the direct route to lysosomes |
| GO:0006518 peptide metabolic process | IDA PMID:25646430 Single liposome analysis of peptide translocation by the ABC... | MARK AS OVER ANNOTATED | Summary: Peptide metabolic process. ABCB9 delivers cytosolic peptides into lysosomes, where lysosomal hydrolases degrade them. Reason: The cited papers measure ABCB9 peptide translocation and ATPase coupling in proteoliposomes. They do not show that ABCB9 catalyses any metabolic conversion of peptides. Lysosomal proteases carry out the degradation. ABCB9's contribution is transmembrane transport, which peptide transport and oligopeptide transmembrane transport already capture. Supporting Evidence: PMID:31417173 TAPL forms a homodimeric transport complex, which translocates oligo- and polypeptides into the lumen of lysosomes driven by ATP hydrolysis. |
| GO:0006518 peptide metabolic process | IDA PMID:31417173 Peptide translocation by the lysosomal ABC transporter TAPL ... | MARK AS OVER ANNOTATED | Summary: Peptide metabolic process. ABCB9 delivers cytosolic peptides into lysosomes, where lysosomal hydrolases degrade them. Reason: The cited papers measure ABCB9 peptide translocation and ATPase coupling in proteoliposomes. They do not show that ABCB9 catalyses any metabolic conversion of peptides. Lysosomal proteases carry out the degradation. ABCB9's contribution is transmembrane transport, which peptide transport and oligopeptide transmembrane transport already capture. Supporting Evidence: PMID:31417173 TAPL forms a homodimeric transport complex, which translocates oligo- and polypeptides into the lumen of lysosomes driven by ATP hydrolysis. |
| GO:0015421 ABC-type oligopeptide transporter activity | EXP PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | EXP PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | EXP PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | EXP PMID:30353140 Structural and functional insights into the interaction and ... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | IDA PMID:15863492 Selective and ATP-dependent translocation of peptides by the... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | IDA PMID:25646430 Single liposome analysis of peptide translocation by the ABC... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | IDA PMID:30877195 Lysosomal targeting of the ABC transporter TAPL is determine... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | IDA PMID:31417173 Peptide translocation by the lysosomal ABC transporter TAPL ... | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015421 ABC-type oligopeptide transporter activity | IEA GO_REF:0000003 | ACCEPT | Summary: ATP-dependent peptide translocation into lysosomes. This is the core activity of ABCB9. Reason: TAPL activity has been shown in reconstituted proteoliposomes, single-liposome assays, isolated lysosomes and membrane vesicles, and it strictly requires ATP hydrolysis. Many substrates are in the oligopeptide range (the 9-mer reporter peptides). Substrates longer than 20 residues are also transported, so the sibling term ABC-type peptide transporter activity is equally apt. Both are kept. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. Peptide transport strictly requires ATP hydrolysis. PMID:17977821 we demonstrate a TAPL-specific translocation of peptides into isolated lysosomes, which strictly requires ATP hydrolysis Reactome:R-HSA-5223317 is a homodimeric ATP-dependent low affinity peptide transporter |
| GO:0015440 ABC-type peptide transporter activity | IBA GO_REF:0000033 | ACCEPT | Summary: ABC-type peptide transporter activity. This is the core activity and covers the broad substrate length range of 6 to 59 residues. Reason: The term describes ATP-driven transport of peptides of any length. ABCB9 transports peptides up to at least 59 residues long, so this term fits the full substrate range. The IBA placement in the ABCB9/TAP clade is consistent with ABCB9's own experimental data. Supporting Evidence: PMID:15863492 The peptide specificity is very broad, ranging from 6-mer up to at least 59-mer peptides with a preference for 23-mers. PMID:18434309 acts as an ATP-dependent polypeptide transporter with broad length selectivity |
| GO:0015440 ABC-type peptide transporter activity | IDA PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: ABC-type peptide transporter activity. This is the core activity and covers the broad substrate length range of 6 to 59 residues. Reason: The term describes ATP-driven transport of peptides of any length. ABCB9 transports peptides up to at least 59 residues long, so this term fits the full substrate range. The IBA placement in the ABCB9/TAP clade is consistent with ABCB9's own experimental data. Supporting Evidence: PMID:15863492 The peptide specificity is very broad, ranging from 6-mer up to at least 59-mer peptides with a preference for 23-mers. PMID:18434309 acts as an ATP-dependent polypeptide transporter with broad length selectivity |
| GO:0015440 ABC-type peptide transporter activity | IDA PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | ACCEPT | Summary: ABC-type peptide transporter activity. This is the core activity and covers the broad substrate length range of 6 to 59 residues. Reason: The term describes ATP-driven transport of peptides of any length. ABCB9 transports peptides up to at least 59 residues long, so this term fits the full substrate range. The IBA placement in the ABCB9/TAP clade is consistent with ABCB9's own experimental data. Supporting Evidence: PMID:15863492 The peptide specificity is very broad, ranging from 6-mer up to at least 59-mer peptides with a preference for 23-mers. PMID:18434309 acts as an ATP-dependent polypeptide transporter with broad length selectivity |
| GO:0015440 ABC-type peptide transporter activity | IDA PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | ACCEPT | Summary: ABC-type peptide transporter activity. This is the core activity and covers the broad substrate length range of 6 to 59 residues. Reason: The term describes ATP-driven transport of peptides of any length. ABCB9 transports peptides up to at least 59 residues long, so this term fits the full substrate range. The IBA placement in the ABCB9/TAP clade is consistent with ABCB9's own experimental data. Supporting Evidence: PMID:15863492 The peptide specificity is very broad, ranging from 6-mer up to at least 59-mer peptides with a preference for 23-mers. PMID:18434309 acts as an ATP-dependent polypeptide transporter with broad length selectivity |
| GO:0015440 ABC-type peptide transporter activity | IEA GO_REF:0000120 | ACCEPT | Summary: ABC-type peptide transporter activity. This is the core activity and covers the broad substrate length range of 6 to 59 residues. Reason: The term describes ATP-driven transport of peptides of any length. ABCB9 transports peptides up to at least 59 residues long, so this term fits the full substrate range. The IBA placement in the ABCB9/TAP clade is consistent with ABCB9's own experimental data. Supporting Evidence: PMID:15863492 The peptide specificity is very broad, ranging from 6-mer up to at least 59-mer peptides with a preference for 23-mers. PMID:18434309 acts as an ATP-dependent polypeptide transporter with broad length selectivity |
| GO:0015833 peptide transport | IDA PMID:15863492 Selective and ATP-dependent translocation of peptides by the... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IDA PMID:17977821 Identification of a lysosomal peptide transport system induc... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IDA PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IDA PMID:22641697 The lysosomal polypeptide transporter TAPL is stabilized by ... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IDA PMID:25646430 Single liposome analysis of peptide translocation by the ABC... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IDA PMID:31417173 Peptide translocation by the lysosomal ABC transporter TAPL ... | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0015833 peptide transport | IEA GO_REF:0000002 | ACCEPT | Summary: Peptide transport from the cytosol into the lysosomal lumen. Reason: ABCB9 directly translocates peptides across the lysosomal membrane. GO has no peptide transmembrane transport process term for peptides longer than oligopeptides, so peptide transport is the appropriate process term. It is retained alongside oligopeptide transmembrane transport. Supporting Evidence: PMID:20377823 translocates a broad spectrum of peptides from the cytosol into the lumen of lysosomes |
| GO:0016020 membrane | IBA GO_REF:0000033 | MODIFY | Summary: Membrane. Correct but uninformative; ABCB9 is a multi-pass protein of the lysosomal membrane. Reason: The term is true but too general. The evidence supports lysosomal membrane (GO:0005765), which the gene already carries with many experimental annotations. Propagation Review Root cause: NO FAILURE NON CORE Sources checked: PANTHER:PTN002517083 SUPPORTS TRANSFER Deep ABCB-family ancestor carrying a generic membrane IBD; correct for ABCB9 but less specific than its lysosomal-membrane localization. Proposed replacements: lysosomal membrane Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. |
| GO:0016020 membrane | IDA PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | MODIFY | Summary: Membrane. Correct but uninformative; ABCB9 is a multi-pass protein of the lysosomal membrane. Reason: The term is true but too general. The evidence supports lysosomal membrane (GO:0005765), which the gene already carries with many experimental annotations. Proposed replacements: lysosomal membrane Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. |
| GO:0016020 membrane | IEA GO_REF:0000120 | MODIFY | Summary: Membrane. Correct but uninformative; ABCB9 is a multi-pass protein of the lysosomal membrane. Reason: The term is true but too general. The evidence supports lysosomal membrane (GO:0005765), which the gene already carries with many experimental annotations. Proposed replacements: lysosomal membrane Supporting Evidence: PMID:10748049 ABCB9 protein colocalized with the lysosomal markers, LAMP1 and LAMP2, in transfected cells. |
| GO:0016887 ATP hydrolysis activity | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: ATP hydrolysis activity of the nucleotide-binding domains, which powers transport. Reason: TAPL has measurable basal and peptide-modulated ATPase activity. ATP hydrolysis is a component of the ABC transport cycle rather than a separate function; the core activity is captured by ABC-type peptide transporter activity. Supporting Evidence: PMID:31417173 TAPL shows a basal ATPase activity, which is inhibited in the presence of longer peptides. |
| GO:0022857 transmembrane transporter activity | IDA PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | MODIFY | Summary: Transmembrane transporter activity. Correct but too general. Reason: The reconstitution data in the cited paper support the specific ABC-type peptide transporter activity, which the gene already carries. Proposed replacements: ABC-type peptide transporter activity ABC-type oligopeptide transporter activity Supporting Evidence: PMID:18434309 TAPL was isolated in a two-step procedure with high purity and, subsequently, reconstituted into proteoliposomes. |
| GO:0035672 oligopeptide transmembrane transport | IEA GO_REF:0000108 | ACCEPT | Summary: Oligopeptide transmembrane transport, inferred from the oligopeptide transporter activity. Reason: This follows logically from the experimentally established ABC-type oligopeptide transporter activity (peptides moved from the cytosol to the lysosomal lumen). Supporting Evidence: PMID:25646430 We reconstituted the human lysosomal polypeptide ABC transporter TAPL, expressed in Pichia pastoris, into lipid vesicles (liposomes) and performed explicit transport measurements. |
| GO:0042803 protein homodimerization activity | IDA PMID:18434309 Peptide specificity and lipid activation of the lysosomal tr... | KEEP AS NON CORE | Summary: Homodimerization. The functional transporter is a homodimer of two half-transporters. Reason: TAPL is a half-size ABC transporter that must homodimerize to form the transport unit. Crosslinking and coimmunoprecipitation of the core domains support this. Dimerization is a structural prerequisite for the transporter activity rather than a separate function. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex PMID:18952056 both the core domain (Arg(141)-Ala(766)) and full-length protein mutually interacted |
| GO:0042803 protein homodimerization activity | IPI PMID:18952056 Functional dissection of transmembrane domains of human TAP-... | KEEP AS NON CORE | Summary: Homodimerization. The functional transporter is a homodimer of two half-transporters. Reason: TAPL is a half-size ABC transporter that must homodimerize to form the transport unit. Crosslinking and coimmunoprecipitation of the core domains support this. Dimerization is a structural prerequisite for the transporter activity rather than a separate function. Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex PMID:18952056 both the core domain (Arg(141)-Ala(766)) and full-length protein mutually interacted |
| GO:0055085 transmembrane transport | IBA GO_REF:0000033 | MODIFY | Summary: Transmembrane transport. Correct but too general. Reason: The specific process is the movement of peptides across the lysosomal membrane. The more specific term is oligopeptide transmembrane transport (GO:0035672), which the gene already carries. Propagation Review Root cause: NO FAILURE NON CORE Sources checked: PANTHER:PTN000657189 SUPPORTS TRANSFER Deep ABC-transporter ancestor carrying generic transmembrane transport; correct for ABCB9 but less specific than oligopeptide transmembrane transport. Proposed replacements: oligopeptide transmembrane transport Supporting Evidence: PMID:17977821 TAPL-specific translocation of peptides into isolated lysosomes |
| GO:0055085 transmembrane transport | IEA GO_REF:0000002 | MODIFY | Summary: Transmembrane transport. Correct but too general. Reason: The specific process is the movement of peptides across the lysosomal membrane. The more specific term is oligopeptide transmembrane transport (GO:0035672), which the gene already carries. Proposed replacements: oligopeptide transmembrane transport Supporting Evidence: PMID:17977821 TAPL-specific translocation of peptides into isolated lysosomes |
| GO:0140359 ABC-type transporter activity | IEA GO_REF:0000002 | MODIFY | Summary: ABC-type transporter activity. Correct but too general. Reason: The substrate is known (peptides), so the specific child term ABC-type peptide transporter activity should be used. Proposed replacements: ABC-type peptide transporter activity Supporting Evidence: PMID:15863492 TAPL forms a homodimeric complex, which translocates peptides across the membrane. |
Loading supporting content…
Download this section (compressed HTML)Q: Which physiological peptide pools does ABCB9 deliver into lysosomes, and does its activity feed lysosomal MHC class II or TAP-independent cross-presentation pathways in dendritic cells?
Q: Does ABCB9 have a specialized role in Sertoli cells, where it is most highly expressed?
Experiment: Peptidomics of lysosomes purified from ABCB9-knockout versus wild-type dendritic cells or macrophages, to define endogenous substrates and test for effects on MHC class II and cross-presentation.
Experiment: Surface biotinylation together with lysosome immunoprecipitation (LysoIP) of endogenous ABCB9, to confirm that no detectable cell-surface pool exists.
Loading supporting content…
Download this section (compressed HTML)Loading supporting content…
Download this section (compressed HTML)