Vesicle-associated membrane protein-associated protein A (VAPA)

The protein contains 249 amino acids for an estimated molecular weight of 27893 Da.

 

Binds to OSBPL3, which mediates recruitment of VAPA to plasma membrane sites (PubMed:25447204). The ORP3-VAPA complex stimulates RRAS signaling which in turn attenuates integrin beta-1 (ITGB1) activation at the cell surface (PubMed:25447204). With OSBPL3, may regulate ER morphology (PubMed:16143324). May play a role in vesicle trafficking (PubMed:11511104, PubMed:19289470). (updated: Jan. 31, 2018)

Protein identification was indicated in the following studies:

  1. Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
  2. Lange and co-workers. (2014) Annotating N termini for the human proteome project: N termini and Nα-acetylation status differentiate stable cleaved protein species from degradation remnants in the human erythrocyte proteome. J Proteome Res. 13(4), 2028-2044.
  3. Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
  4. Wilson and co-workers. (2016) Comparison of the Proteome of Adult and Cord Erythroid Cells, and Changes in the Proteome Following Reticulocyte Maturation. Mol Cell Proteomics. 15(6), 1938-1946.
  5. Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
  6. D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
  7. Chu and co-workers. (2018) Quantitative mass spectrometry of human reticulocytes reveal proteome-wide modifications during maturation. Br J Haematol. 180(1), 118-133.

Methods

The following articles were analysed to gather the proteome content of erythrocytes.

The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.

PublicationIdentification 1Uniprot mapping 2Not mapped /
Obsolete
TrEMBLSwiss-Prot
Goodman (2013)2289 (gene list)227853205992269
Lange (2014)123412347281224
Hegedus (2015)2638262202352387
Wilson (2016)165815281702911068
d'Alessandro (2017)18261817201815
Bryk (2017)20902060101081942
Chu (2018)18531804553621387

1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry

The compilation of older studies can be retrieved from the Red Blood Cell Collection database.

The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.

No sequence conservation computed yet.

This protein is annotated as membranous in Gene Ontology, is annotated as membranous in UniProt, is predicted to be membranous by TOPCONS.


Interpro domains
Total structural coverage: 59%
Model score: 39

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VariantDescription
dbSNP:rs1044163
dbSNP:rs1127666

The reference OMIM entry for this protein is 605703

Vesicle-associated membrane protein-associated protein a; vapa
Vamp-associated protein a
Vamp-associated protein, 33-kd; vap33

DESCRIPTION

SNAREs (see 603215) are compartmentally specific, cytoplasmically oriented integral membrane proteins involved in the fusion of membranes and the transport of intracellular proteins. Recognition of vesicles and target membranes is mediated by v-SNAREs (e.g., VAMP8; 603177) and t-SNAREs (e.g., SNAP23; 602534), respectively.

CLONING

By searching an EST database for human homologs of the Aplysia 33-kD VAMP-associated protein (Vap33), Weir et al. (1998) identified a cDNA encoding VAPA, which they termed VAP33. Sequence analysis predicted that the 242-amino acid protein, which is 50% identical to the molluscan sequence, contains 8 potential phosphorylation sites, an alpha-helical coiled-coil domain, and a C-terminal transmembrane domain. Northern blot analysis of mouse tissues detected a major 1.9-kb transcript and minor 3.9- and 7.1-kb transcripts in all tissues tested, with highest expression in brain, testis, ovary, kidney and skeletal muscle. In contrast, Vap33 expression is neuron specific in Aplysia. Nishimura et al. (1999) identified cDNAs encoding VAPA and the 60% homologous VAPB (605704). Northern blot analysis detected a 1.7-kb VAPA transcript in all human tissues tested.

GENE FUNCTION

By Western blot analysis, Weir et al. (1998) showed that VAPA interacts with VAMP1 (185880) and VAMP2 (185881) but not with SNAP25 (600322). By SDS-PAGE analysis, Nishimura et al. (1999) demonstrated that the transmembrane domain of recombinant VAPA interacted with VAPA and VAPB fusion proteins.

MAPPING

The International Radiation Hybrid Mapping Consortium mapped the VAPA gene to chromosome 18 (TMAP stSG49693). ... More on the omim web site

Subscribe to this protein entry history

Feb. 10, 2018: Protein entry updated
Automatic update: Entry updated from uniprot information.

Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated

Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated

March 16, 2016: Protein entry updated
Automatic update: OMIM entry 605703 was added.

Feb. 24, 2016: Protein entry updated
Automatic update: model status changed