Swr1 subfamily

The archetype of the Swr1 subfamily is Swr1p (SWI/SNF-related protein) from S cerevisiae which is part of the large SWR1 complex that exchanges histone H2A.Z-containing for wild type H2A-containing dimers 1, 2, 3, 4.

Three other characterised proteins belong to the subfamily:

PIE1 is involved in the A thaliana vernalisation regulation (Photoperiod-Independent Early flowering 5) through a pathway intimately linked with histone lysine methylation events 6.

D melanogaster Domino is an essential, development-linked protein 7 and alleles can suppress position effect variegation, implying they may be linked to heterochromatin functions. Domino participates in a complex that combines components of the homologous yeast SWR1 and NuA4 complexes 8, and has been shown to function in acetylation dependent histone variant exchange within the TRRAP/TIP60 complex 9.

Human SRCAP (Snf2p-Related CBP Activating Protein 10) acts as a transcriptional co-activator of steroid hormone dependent genes and has recently been shown to be a component of a human TRRAP/TIP60 complex 11 and other complexes (see EP400 below). It also interacts with several coactivators including CBP 10, 12. It has recently been shown that SRCAP can rescue D melanogaster domino mutants 13.

names associated with subfamilies members
SRCAP, Snf2-related CBP activator protein, dom, domino, PIE1
1: Krogan, N. J., M. C. Keogh, et al. (2003). A Snf2 family ATPase complex required for recruitment of the histone H2A variant Htz1. Mol Cell 12(6): 1565-76. PubMed
2: Kobor, M. S., S. Venkatasubrahmanyam, et al. (2004). A protein complex containing the conserved Swi2/Snf2-related ATPase Swr1p deposits histone variant H2A.Z into euchromatin. PLoS Biol 2(5): E131. PubMed
3: Mizuguchi, G., X. Shen, et al. (2004). ATP-driven exchange of histone H2AZ variant catalyzed by SWR1 chromatin remodeling complex. Science 303(5656): 343-8. PubMed
4: Wu, W. H., S. Alami, et al. (2005). Swc2 is a widely conserved H2AZ-binding module essential for ATP-dependent histone exchange. Nat Struct Mol Biol 12(12): 1064-71. PubMed
5: Noh, Y. S. and R. M. Amasino (2003). PIE1, an ISWI family gene, is required for FLC activation and floral repression in Arabidopsis. Plant Cell 15(7): 1671-82. PubMed
6: He, Y. and R. M. Amasino (2005). Role of chromatin modification in flowering-time control. Trends Plant Sci 10(1): 30-5. PubMed
7: Ruhf, M. L., A. Braun, et al. (2001). The domino gene of Drosophila encodes novel members of the SWI2/SNF2 family of DNA-dependent ATPases, which contribute to the silencing of homeotic genes. Development 128(8): 1429-41. PubMed
8: Doyon, Y. and J. Cote (2004). The highly conserved and multifunctional NuA4 HAT complex. Curr Opin Genet Dev 14(2): 147-54. PubMed
9: Kusch, T., L. Florens, et al. (2004). Acetylation by Tip60 is required for selective histone variant exchange at DNA lesions. Science 306(5704): 2084-7. PubMed
10: Johnston, H., J. Kneer, et al. (1999). Identification of a novel SNF2/SWI2 protein family member, SRCAP, which interacts with CREB-binding protein. J Biol Chem 274(23): 16370-6. PubMed
11: Cai, Y., J. Jin, et al. (2005). The mammalian YL1 protein is a shared subunit of the TRRAP/TIP60 histone acetyltransferase and SRCAP complexes. J Biol Chem 280(14): 13665-70. PubMed
12: Monroy, M. A., N. M. Schott, et al. (2003). SNF2-related CBP activator protein (SRCAP) functions as a coactivator of steroid receptor-mediated transcription through synergistic interactions with CARM-1 and GRIP-1. Mol Endocrinol 17(12): 2519-28. PubMed
13: Eissenberg, J. C., M. Wong, et al. (2005). Human SRCAP and Drosophila melanogaster DOM are homologs that function in the notch signaling pathway. Mol Cell Biol 25(15): 6559-69. PubMed