Arf-GAP with coiled-coil, ANK repeat and PH domain-containing protein 2 (ACAP2)
The protein contains 778 amino acids for an estimated molecular weight of 88029 Da.
GTPase-activating protein (GAP) for ADP ribosylation factor 6 (ARF6). (updated: March 4, 2015)
Protein identification was indicated in the following studies:
- Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
- 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.
- 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.
- 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.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
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.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
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.
(right-click above to access to more options from the contextual menu)
No binding partner found
The reference OMIM entry for this protein is 607766
Centaurin, beta-2; centb2
Kiaa0041
Arf-gap with coiled-coil, ankyrin repeat, and pleckstrin homology domains 2; acap2
CLONING
By sequencing clones obtained from a size-fractionated myeloid cell line cDNA library, Nomura et al. (1994) cloned a partial cDNA encoding CENTB2, which they designated KIAA0041. The 3-prime untranslated region of the CENTB2 mRNA contains an Alu repeat. CENTB2 shares 52% sequence identity with CENTB1 (607763) and about 28% identity with ankyrin (see 106410). Northern blot analysis revealed ubiquitous expression, with highest levels detected in peripheral blood leukocytes, followed by placenta, kidney, spleen, and ovary. Lowest levels were detected in brain. Using the partial KIAA0041 sequence as probe, Jackson et al. (2000) obtained a full-length cDNA encoding CENTB2, which they designated ACAP2, from a lymphocyte cDNA library. The deduced 778-amino acid protein contains 2 N-terminal coiled-coil regions, a pleckstrin homology (PH) domain, an ARF-GAP domain (see ARF6; 600464), and C-terminal ankyrin repeats. ACAP2 shares significant similarity with CENTB1, which the authors called ACAP1, and 95% identity with mouse Acap2. It also shares similarity with ASAP1 (605953) and PAP (603817) in the ARF-GAP domain and in the overall domain structure. Jackson et al. (2000) also identified homologous sequences in C. elegans, A. thaliana, and D. melanogaster. By PCR, they detected ACAP2 mRNA expressed at similar levels in all tissues examined. Western blot analysis detected ACAP2 expression in all cell lines examined. By Northern blot analysis, Dowler et al. (2000) detected expression of a 4.5-kb Centb2 transcript in all mouse tissues tested.GENE FUNCTION
Jackson et al. (2000) determined that ACAP1 and ACAP2 were recruited to platelet-derived growth factor (PDGF; see 173430)-induced dorsal membrane ruffles in NIH 3T3 mouse fibroblasts, and overexpression inhibited ruffle formation. In vitro, ACAP1 and ACAP2 preferred ARF6 as substrate rather than ARF1 (103180) or ARF5 (103188), and the GAP activity of both ACAPs was dependent upon phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). Mutation of a highly conserved arginine in both ACAPs resulted in lack of ARF-GAP activity. Overexpression in HeLa cells of either ACAP blocked the formation of ARF6-dependent protrusions. Both ACAPs were also recruited to peripheral, tubular membranes, where activation of ARF6 occurs and allows membrane recycling back to the plasma membrane. Dowler et al. (2000) determined that the isolated PH domain of mouse Centb2 exhibited moderate affinity for PtdIns(3,5)P2, but it did not bind any other phosphoinositides tested, including PtdIns(4,5)P2.MAPPING
By PCR of a human/rodent hybrid panel, Nomura et al. (1994) mapped the CENTB2 gene to chromosome 3. ... More on the omim web site
Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated
Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated
Nov. 23, 2017: Protein entry updated
Automatic update: Uniprot description updated
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 607766 was added.