F-actin-capping protein subunit alpha-2 (CAPZA2)
The protein contains 286 amino acids for an estimated molecular weight of 32949 Da.
F-actin-capping proteins bind in a Ca(2+)-independent manner to the fast growing ends of actin filaments (barbed end) thereby blocking the exchange of subunits at these ends. Unlike other capping proteins (such as gelsolin and severin), these proteins do not sever actin filaments. (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.
- 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.
- 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.
| 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.
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Biological Process
Actin cytoskeleton organization
Antigen processing and presentation of exogenous peptide antigen via MHC class II
Barbed-end actin filament capping
Blood coagulation
Endoplasmic reticulum to Golgi vesicle-mediated transport
Innate immune response
Movement of cell or subcellular component
Protein complex assembly
Protein-containing complex assembly
The reference OMIM entry for this protein is 601571
Capping protein, alpha-2; capza2
Cap protein, actin, alpha-2 subunit; cappa2
CLONING
Barron-Casella et al. (1995) stated that CapZ was identified in chicken as a nonsevering, barbed-end actin-binding protein composed of alpha and beta subunits. In the chicken, 2 cDNAs were isolated for the alpha subunit. The alpha-1 (CAPZA1; 601580) and alpha-2 isoforms, which share 85% identity, are the products of 2 separate genes; 1 gene appears to be responsible for beta-subunit expression (CAPZB; 601572). By capping the barbed end of actin filaments, CapZ regulates the growth of the actin filament at the barbed end. Barron-Casella et al. (1995) isolated human retinal cDNAs that are homologs of the alpha-2 and beta subunits of chicken CapZ. The derived human alpha-2 subunit shares 95% amino acid identity with the chicken alpha-2 subunit; the beta subunit is 99% identical to chicken subunit residues 1-243. The remaining portion of the human beta subunit (amino acids 244-272) diverges significantly with only 8 out of 29 C-terminal amino acids conserved between the 2 species.MAPPING
Barron-Casella et al. (1995) mapped the CAPZA2 gene to chromosome 7q31.2-q31.3 by PCR screening of the NIGMS human/rodent somatic cell hybrid mapping panel 2, with refinement by PCR analysis of a human chromosome 7-specific YAC library. One set of overlapping clones contained both the MET gene (164860) and the CAPZA2 gene. The 2 genes were separated by a maximum distance of 330 kb, with MET centromeric and WNT2 (147870) and CFTR (602421) distal to CAPZA2. Hart et al. (1997) cloned the mouse homolog of the CAPZA2 gene. By interspecific backcross analysis, they mapped the mouse Capza2 gene to chromosome 6, in a region that shows conservation of synteny with human 7q31.2-q31.3. ... 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
June 20, 2017: Protein entry updated
Automatic update: comparative model was added.
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 601571 was added.