Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2017 Dec 26;114(52):E11208-E11217. doi: 10.1073/pnas.1714579115. Epub 2017 Dec 13.

Ser7 of RNAPII-CTD facilitates heterochromatin formation by linking ncRNA to RNAi.

Author information

1
Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan; kajitani@sci.hokudai.ac.jp yota@sci.hokudai.ac.jp.
2
Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
3
Department of Biochemistry, Shimane University School of Medicine, Izumo, Shimane 693-8501, Japan.
4
Frontier Research Laboratory, Advanced ICT Research Institute, National Institute of Information and Communications Technology, Kobe, Hyogo 651-2492, Japan.
5
Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan.
6
Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
7
Division of Transcriptomics, Medical Institute of Bioregulation, Japan Science and Technology Agency-Core Research for Evolutional Science and Technology, Kyushu University, Fukuoka 812-8582, Japan.
8
Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
9
Namur Research College, University of Namur, 5000 Namur, Belgium.

Abstract

Some long noncoding RNAs (ncRNAs) transcribed by RNA polymerase II (RNAPII) are retained on chromatin, where they regulate RNAi and chromatin structure. The molecular basis of this retention remains unknown. We show that in fission yeast serine 7 (Ser7) of the C-terminal domain (CTD) of RNAPII is required for efficient siRNA generation for RNAi-dependent heterochromatin formation. Surprisingly, Ser7 facilitates chromatin retention of nascent heterochromatic RNAs (hRNAs). Chromatin retention of hRNAs and siRNA generation requires both Ser7 and an RNA-binding activity of the chromodomain of Chp1, a subunit of the RNA-induced transcriptional silencing (RITS) complex. Furthermore, RITS associates with RNAPII in a Ser7-dependent manner. We propose that Ser7 promotes cotranscriptional chromatin retention of hRNA by recruiting the RNA-chromatin connector protein Chp1, which facilitates RNAi-dependent heterochromatin formation. Our findings reveal a function of the CTD code: linking ncRNA transcription to RNAi for heterochromatin formation.

KEYWORDS:

RNA polymerase II; RNAi; heterochromatin; noncoding RNA

PMID:
29237752
PMCID:
PMC5748204
DOI:
10.1073/pnas.1714579115
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center