Summary: F-actin capping protein, beta subunit
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F-actin capping protein Edit Wikipedia article
|F-actin capping protein alpha subunit|
solution nmr structure of s100b bound to the high-affinity target peptide trtk-12
|F-actin capping protein, beta subunit|
In molecular biology, the F-actin capping protein is a protein which binds in a calcium-independent manner to the fast-growing ends of actin filaments (barbed end), thereby blocking the exchange of subunits at these ends. Unlike gelsolin and severin this protein does not sever actin filaments. The F-actin capping protein is a heterodimer composed of two unrelated subunits: alpha and beta. Neither of the subunits shows sequence similarity to other filament-capping proteins. The alpha subunit is a protein of about 268 to 286 amino acid residues and the beta subunit is approximately 280 amino acids, their sequences are well conserved in eukaryotic species.
The actin filament system, a prominent part of the cytoskeleton in eukaryotic cells, is both a static structure and a dynamic network that can undergo rearrangements: it is thought to be involved in processes such as cell movement and phagocytosis, as well as muscle contraction.
- Maruyama K, Kurokawa H, Oosawa M, Shimaoka S, Yamamoto H, Ito M, Maruyama K (May 1990). "Beta-actinin is equivalent to Cap Z protein". J. Biol. Chem. 265 (15): 8712–5. PMID 2341404.
- Cooper JA, Caldwell JE, Gattermeir DJ, Torres MA, Amatruda JF, Casella JF (1991). "Variant cDNAs encoding proteins similar to the alpha subunit of chicken CapZ". Cell Motil. Cytoskeleton. 18 (3): 204–14. doi:10.1002/cm.970180306. PMID 1711931.
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This tab holds annotation information from the InterPro database.
InterPro entry IPR001698
The F-actin capping protein binds in a calcium-independent manner to the fast growing ends of actin filaments (barbed end) and thereby restricts its growth. The F-actin capping protein is a heterodimer composed of two unrelated subunits: alpha and beta. Neither of the subunits shows sequence similarity to other filament-capping proteins [ PUBMED:2341404 ].
This entry represents the beta subunit (CAPZB), which is a protein of about 280 amino acid residues whose sequence is well conserved in eukaryotic species [ PUBMED:2179733 ]. In Drosophila mutations in the alpha and beta subunits cause actin accumulation and subsequent retinal degeneration [ PUBMED:16143599 ]. In humans CAPZB is part of the WASH complex that controls the fission of endosomes [ PUBMED:19922875 ].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||F-actin capping protein complex (GO:0008290)|
|Biological process||barbed-end actin filament capping (GO:0051016)|
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Key: available, not generated, — not available.
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|Author:||Finn RD , Bateman A|
|Number in seed:||82|
|Number in full:||2005|
|Average length of the domain:||222.10 aa|
|Average identity of full alignment:||57 %|
|Average coverage of the sequence by the domain:||79.46 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||20|
|Download:||download the raw HMM for this family|
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the F_actin_cap_B domain has been found. There are 47 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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AlphaFold Structure Predictions
The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.