The Chp1–Tas3 core is a multifunctional platform critical for gene silencing by RITS
RNA interference (RNAi) is critical for the assembly of heterochromatin at Schizosaccharomyces pombe centromeres. Central to this process is the RNA-induced initiation of transcriptional gene silencing (RITS) complex, which physically anchors small noncoding RNAs to chromatin. RITS includes Ago1, the chromodomain protein Chp1, and Tas3, which forms a bridge between Chp1 and Ago1. Chp1 is a large protein with no recognizable domains, apart from its chromodomain. Here we describe how the structured C-terminal half of Chp1 binds the Tas3 N-terminal domain, revealing the tight association of Chp1 and Tas3. The structure also shows a PIN domain at the C-terminal tip of Chp1 that controls subtelomeric transcripts through a post-transcriptional mechanism. We suggest that the Chp1–Tas3 complex provides a solid and versatile platform to recruit both RNAi-dependent and RNAi-independent gene-silencing pathways for locus-specific regulation of heterochromatin.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC02-98CH10886
- OSTI ID:
- 1069832
- Report Number(s):
- BNL-100404-2013-JA
- Journal Information:
- Nature Structural & Molecular Biology, Vol. 18, Issue 12; ISSN 1545-9993
- Publisher:
- Nature Publishing Group
- Country of Publication:
- United States
- Language:
- English
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