id: Q9P7N2
gene_symbol: vas2
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:284812
  label: Schizosaccharomyces pombe (strain 972 / ATCC 24843)
description: Vas2 (Aps1) is the sigma subunit of the heterotetrameric AP-1 clathrin adaptor complex. It
  associates with the gamma subunit Apl4 and contributes to assembly and membrane recruitment of AP-1
  at the Golgi and endosomal system. The complex sorts membrane-protein cargo into intracellular transport
  carriers and supports exit of cargo such as the v-SNARE Syb1 from endosomes.
existing_annotations:
- term:
    id: GO:0005634
    label: nucleus
  evidence_type: HDA
  original_reference_id: PMID:16823372
  qualifier: is_active_in
  review:
    summary: nucleus is retained as an ancillary annotation.
    action: KEEP_AS_NON_CORE
    reason: Retain the reported nuclear signal from the tagged-protein screen as an ancillary localization.
      It does not establish a nuclear AP-1 cargo-sorting mechanism and is not the principal functional
      location supported by endosomal trafficking experiments.
    supported_by:
    - &id001
      reference_id: PMID:16823372
      supporting_text: Next, we determined the localization of 4,431 proteins, corresponding to approximately
        90% of the fission yeast proteome, by tagging each ORF with the yellow fluorescent protein.
    - &id002
      reference_id: PMID:19624755
      supporting_text: In pull-down assay, Apm1 binds Apl2 even in the absence of Aps1 and Apl4, and Apl4
        binds Aps1 even in the absence of Apm1 and Apl2. Consistently, the deletion of any subunit generally
        caused the disassociation of the heterotetrameric complex from endosomes, although some subunits
        weakly localized to endosomes. In addition, the deletion of individual subunits caused similar
        endosomal accumulation of v-SNARE synaptobrevin Syb1. Altogether, results suggest that the four
        subunits are all essential for the heterotetrameric complex formation and for the AP-1 function
        in exit transport from endosomes.
- term:
    id: GO:0005634
    label: nucleus
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  supporting_entities:
  - UniProtKB-SubCell:SL-0191
  review:
    summary: nucleus is retained as an ancillary annotation.
    action: KEEP_AS_NON_CORE
    reason: Retain the reported nuclear signal from the tagged-protein screen as an ancillary localization.
      It does not establish a nuclear AP-1 cargo-sorting mechanism and is not the principal functional
      location supported by endosomal trafficking experiments.
    supported_by:
    - *id001
    - *id002
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: EXP
  original_reference_id: PMID:16823372
  qualifier: located_in
  review:
    summary: cytoplasm is supported.
    action: ACCEPT
    reason: AP-1 is a peripheral membrane adaptor recruited from the cytoplasm. Cytoplasmic and cytosolic
      pools are consistent with the localization screen and the membrane recruitment behavior of the complex.
    supported_by:
    - *id001
    - *id002
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  supporting_entities:
  - UniProtKB-SubCell:SL-0086
  review:
    summary: cytoplasm is supported.
    action: ACCEPT
    reason: AP-1 is a peripheral membrane adaptor recruited from the cytoplasm. Cytoplasmic and cytosolic
      pools are consistent with the localization screen and the membrane recruitment behavior of the complex.
    supported_by:
    - *id001
    - *id002
- term: &id009
    id: GO:0005768
    label: endosome
  evidence_type: IDA
  original_reference_id: PMID:19624755
  qualifier: is_active_in
  review:
    summary: endosome is supported.
    action: ACCEPT
    reason: Fission yeast AP-1 subunit deletions alter recruitment to endosomes and trap Syb1 in the endosomal
      system. The Golgi/endosome-associated clathrin adaptor location is consistent with the conserved
      AP-1 coat function and the curated target-specific localization observations.
    supported_by:
    - *id002
- term:
    id: GO:0005768
    label: endosome
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  supporting_entities:
  - UniProtKB-SubCell:SL-0101
  review:
    summary: endosome is supported.
    action: ACCEPT
    reason: Fission yeast AP-1 subunit deletions alter recruitment to endosomes and trap Syb1 in the endosomal
      system. The Golgi/endosome-associated clathrin adaptor location is consistent with the conserved
      AP-1 coat function and the curated target-specific localization observations.
    supported_by:
    - *id002
- term: &id010
    id: GO:0005794
    label: Golgi apparatus
  evidence_type: IDA
  original_reference_id: PMID:19624755
  qualifier: is_active_in
  review:
    summary: Golgi apparatus is supported.
    action: ACCEPT
    reason: Fission yeast AP-1 subunit deletions alter recruitment to endosomes and trap Syb1 in the endosomal
      system. The Golgi/endosome-associated clathrin adaptor location is consistent with the conserved
      AP-1 coat function and the curated target-specific localization observations.
    supported_by:
    - *id002
- term:
    id: GO:0005794
    label: Golgi apparatus
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  supporting_entities:
  - UniProtKB-SubCell:SL-0132
  review:
    summary: Golgi apparatus is supported.
    action: ACCEPT
    reason: Fission yeast AP-1 subunit deletions alter recruitment to endosomes and trap Syb1 in the endosomal
      system. The Golgi/endosome-associated clathrin adaptor location is consistent with the conserved
      AP-1 coat function and the curated target-specific localization observations.
    supported_by:
    - *id002
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: HDA
  original_reference_id: PMID:16823372
  qualifier: is_active_in
  review:
    summary: cytosol is supported.
    action: ACCEPT
    reason: AP-1 is a peripheral membrane adaptor recruited from the cytoplasm. Cytoplasmic and cytosolic
      pools are consistent with the localization screen and the membrane recruitment behavior of the complex.
    supported_by:
    - *id001
    - *id002
- term:
    id: GO:0010496
    label: intercellular transport
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: involved_in
  supporting_entities:
  - ARBA:ARBA00092758
  review:
    summary: intercellular transport is not supported for this gene.
    action: REMOVE
    reason: GO:0010496 means movement between cells, as verified in QuickGO. The experimentally established
      Vas2/AP-1 pathway sorts cargo between compartments inside a cell. This ARBA assertion conflates
      intercellular and intracellular transport and lacks an independent intercellular mechanism.
    supported_by:
    - *id002
- term:
    id: GO:0015031
    label: protein transport
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: involved_in
  supporting_entities:
  - InterPro:IPR016635
  review:
    summary: protein transport is supported.
    action: ACCEPT
    reason: The Aps1 sigma subunit is required for normal AP-1 complex formation and exit transport from
      endosomes; loss of individual subunits causes endosomal accumulation of Syb1. Retain the curated
      routes supported by the original target experiments and distinguish them from transport between
      cells.
    supported_by:
    - *id002
- term: &id004
    id: GO:0016192
    label: vesicle-mediated transport
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  supporting_entities:
  - CGD:CAL0000182525
  - FB:FBgn0039132
  - FB:FBgn0043012
  - MGI:MGI:1098244
  - MGI:MGI:1889383
  - PANTHER:PTN000204281
  - PomBase:SPAP27G11.06c
  - RGD:620188
  - SGD:S000003561
  - SGD:S000004160
  - UniProtKB:P53680
  - WB:WBGene00000157
  review:
    summary: vesicle-mediated transport is supported.
    action: ACCEPT
    reason: The Aps1 sigma subunit is required for normal AP-1 complex formation and exit transport from
      endosomes; loss of individual subunits causes endosomal accumulation of Syb1. Retain the curated
      routes supported by the original target experiments and distinguish them from transport between
      cells.
    supported_by:
    - *id002
- term:
    id: GO:0016192
    label: vesicle-mediated transport
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: involved_in
  supporting_entities:
  - ARBA:ARBA00028249
  - InterPro:IPR044733
  review:
    summary: vesicle-mediated transport is supported.
    action: ACCEPT
    reason: The Aps1 sigma subunit is required for normal AP-1 complex formation and exit transport from
      endosomes; loss of individual subunits causes endosomal accumulation of Syb1. Retain the curated
      routes supported by the original target experiments and distinguish them from transport between
      cells.
    supported_by:
    - *id002
- term: &id008
    id: GO:0030121
    label: AP-1 adaptor complex
  evidence_type: IDA
  original_reference_id: PMID:19624755
  qualifier: part_of
  review:
    summary: AP-1 adaptor complex is supported.
    action: ACCEPT
    reason: Pull-downs establish the Apl4-Aps1 association, and subunit deletion analysis establishes
      their contribution to assembly and recruitment of the heterotetrameric AP-1 complex.
    supported_by:
    - *id002
- term:
    id: GO:0030121
    label: AP-1 adaptor complex
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: part_of
  supporting_entities:
  - ARBA:ARBA00085820
  - InterPro:IPR044733
  review:
    summary: AP-1 adaptor complex is supported.
    action: ACCEPT
    reason: Pull-downs establish the Apl4-Aps1 association, and subunit deletion analysis establishes
      their contribution to assembly and recruitment of the heterotetrameric AP-1 complex.
    supported_by:
    - *id002
- term:
    id: GO:0030121
    label: AP-1 adaptor complex
  evidence_type: NAS
  original_reference_id: PMID:19624755
  qualifier: part_of
  review:
    summary: AP-1 adaptor complex is supported.
    action: ACCEPT
    reason: Pull-downs establish the Apl4-Aps1 association, and subunit deletion analysis establishes
      their contribution to assembly and recruitment of the heterotetrameric AP-1 complex.
    supported_by:
    - *id002
- term:
    id: GO:0030276
    label: clathrin binding
  evidence_type: ISO
  original_reference_id: GO_REF:0000024
  qualifier: enables
  supporting_entities:
  - SGD:S000004160
  review:
    summary: clathrin binding is retained as an ancillary annotation.
    action: KEEP_AS_NON_CORE
    reason: Retain the curator-mediated orthology transfer for clathrin association in the AP-1 context.
      The decisive target evidence establishes adaptor-complex assembly; it does not demonstrate that
      isolated sigma subunit is the principal direct clathrin-binding interface.
    supported_by:
    - *id002
- term:
    id: GO:0030665
    label: clathrin-coated vesicle membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  supporting_entities:
  - UniProtKB-SubCell:SL-0071
  review:
    summary: clathrin-coated vesicle membrane is supported.
    action: ACCEPT
    reason: Fission yeast AP-1 subunit deletions alter recruitment to endosomes and trap Syb1 in the endosomal
      system. The Golgi/endosome-associated clathrin adaptor location is consistent with the conserved
      AP-1 coat function and the curated target-specific localization observations.
    supported_by:
    - *id002
- term: &id007
    id: GO:0035615
    label: clathrin-cargo adaptor activity
  evidence_type: IC
  original_reference_id: GO_REF:0000111
  qualifier: contributes_to
  supporting_entities:
  - GO:0030121
  review:
    summary: clathrin-cargo adaptor activity is supported.
    action: ACCEPT
    reason: Aps1 contributes to the clathrin-cargo adaptor function of assembled AP-1, whose four subunits
      organize membrane cargo sorting. The contributes_to row captures this precisely; the broad domain
      mapping should also be interpreted in the obligate adaptor-complex context.
    supported_by:
    - *id002
    - &id003
      reference_id: PMID:17360967
      supporting_text: We report that the gamma/sigma1 or alpha/sigma2 hemicomplexes bound the dileucine-based
        motifs of several proteins quite strongly, whereas binding by the beta1/mu1 and beta2/mu2 hemicomplexes,
        and the individual beta or mu subunits, was extremely weak or undetectable.
- term:
    id: GO:0035615
    label: clathrin-cargo adaptor activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: enables
  supporting_entities:
  - InterPro:IPR044733
  review:
    summary: clathrin-cargo adaptor activity is supported.
    action: ACCEPT
    reason: Aps1 contributes to the clathrin-cargo adaptor function of assembled AP-1, whose four subunits
      organize membrane cargo sorting. The contributes_to row captures this precisely; the broad domain
      mapping should also be interpreted in the obligate adaptor-complex context.
    supported_by:
    - *id002
    - *id003
- term: &id005
    id: GO:0042147
    label: retrograde transport, endosome to Golgi
  evidence_type: IDA
  original_reference_id: PMID:19624755
  qualifier: involved_in
  review:
    summary: retrograde transport, endosome to Golgi is supported.
    action: ACCEPT
    reason: The Aps1 sigma subunit is required for normal AP-1 complex formation and exit transport from
      endosomes; loss of individual subunits causes endosomal accumulation of Syb1. Retain the curated
      routes supported by the original target experiments and distinguish them from transport between
      cells.
    supported_by:
    - *id002
- term: &id006
    id: GO:0099638
    label: endosome to plasma membrane protein transport
  evidence_type: IDA
  original_reference_id: PMID:19624755
  qualifier: involved_in
  review:
    summary: endosome to plasma membrane protein transport is supported.
    action: ACCEPT
    reason: The Aps1 sigma subunit is required for normal AP-1 complex formation and exit transport from
      endosomes; loss of individual subunits causes endosomal accumulation of Syb1. Retain the curated
      routes supported by the original target experiments and distinguish them from transport between
      cells.
    supported_by:
    - *id002
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO terms
  findings: []
- id: GO_REF:0000024
  title: Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator
    judgment of sequence similarity
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping,
    accompanied by conservative changes to GO terms applied by UniProt
  findings: []
- id: GO_REF:0000111
  title: Gene Ontology annotations Inferred by Curator (IC) using at least one Inferred by Sequence Similarity
    (ISS) annotation to support the inference
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning models
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: PMID:16823372
  title: ORFeome cloning and global analysis of protein localization in the fission yeast Schizosaccharomyces
    pombe.
  findings: []
  full_text_unavailable: true
- id: PMID:19624755
  title: Deletion mutants of AP-1 adaptin subunits display distinct phenotypes in fission yeast.
  findings: []
  full_text_unavailable: true
- id: PMID:17360967
  title: The gamma/sigma1 and alpha/sigma2 hemicomplexes of clathrin adaptors AP-1 and AP-2 harbor the
    dileucine recognition site.
  full_text_unavailable: true
core_functions:
- description: Sigma subunit of AP-1 contributing to cargo sorting and vesicular exit transport from endosomes.
  supported_by:
  - *id002
  - *id003
  directly_involved_in:
  - *id004
  - *id005
  - *id006
  contributes_to_molecular_function: *id007
  in_complex: *id008
  locations:
  - *id009
  - *id010