Pathways & interactions
SWR1 chromatin-remodelling complex, subunit Swc7 (IPR020195)
Short name: SWR1_Swc7
Overlapping homologous superfamilies
Th SWR1 complex is involved in chromatin-remodelling by promoting the the ATP-dependent exchange of histone H2A for the H2A variant HZT1 in Saccharomyces cerevisiae (Baker's yeast) or H2AZ in mammals. The SWR1 chromatin-remodelling complex is composed of at least 14 subunits and has a molecular mass of about 1.2 to 1.5 MDa. In S. cerevisiae the core conserved subunits are:
- ATPase; Swr1.
- RuvB-like; Rvb1 and Rvb2.
- Actin; Act1.
- Actin-related: Arp4 and Arp6.
- YEATS protein [PMID: 19234524]; Yaf9.
The non-conserved subunits are: Vps71 (Swc6), Vps72 (Swc2), Swc3, Swc4, Swc5, Swc7, Bdf1 [PMID: 19424290].
Seven of the SWR1 subunits are involved in maintaining complex integrity and H2AZ histone replacement activity: Swr1, Swc2, Swc3, Arp6, Swc5, Yaf9 and Swc6. Arp4 is required for the association of Bdf1, Yaf9, and Swc4 and Arp4 is also required for SWR1 H2AZ histone replacement activity in vitro. Furthermore the N-terminal region of the ATPase Swr1 provides the platform upon which Bdf1, Swc7, Arp4, Act1, Yaf9 and Swc4 associate [PMID: 19088068]; it also contains an additional H2AZ-H2B specific binding site, distinct from the binding site of the Swc2 subunit [PMID: 16299513].
In eukaryotes the deposition of variant histones into nucleosomes by the chromatin-remodelling complexes such as the SWR1 and INO80 complexes have many crucial functions including the control of gene regulation and expression, checkpoint regulation, DNA replication and repair, telomer maintenance and chromosomal segregation and as such represent critical components of pathways that maintain genomic integrity.
This entry represents the subunit Swc7; the smallest subunit of the SWR1 complex. Swc7 is not required for H2AZ binding. Swc7 associates with the N terminus of Swr1, and the association of Bdf1 requires Swc7, Yaf9, and Arp4 [PMID: 19088068].