Journal
MOLECULAR CELL
Volume 29, Issue 3, Pages 313-323Publisher
CELL PRESS
DOI: 10.1016/j.molcel.2008.01.011
Keywords
-
Categories
Funding
- NIGMS NIH HHS [R01 GM046498, GM46498, R01 GM056663, R01 GM046498-17, R01 GM056663-09, GM56663] Funding Source: Medline
Ask authors/readers for more resources
Within the heterochromatin of budding yeast, RNA polymerase II (RNAPII) transcription is repressed by the Sir2 deacetylase. Although heterochromatic silencing is generally thought to be due to limited accessibility of the underlying DNA, there are several reports of RNAPII and basal transcription factors within silenced regions. Analysis of the rDNA array revealed cryptic RNAPII transcription within the non-transcribed spacer region. These transcripts are terminated by the Nrd1 /Sen1 complex and degraded by the exosome. Mutations in this pathway lead to decreased silencing and dramatic chromatin changes in the rDNA locus. Interestingly, Nrd1 mutants also show higher levels of rDNA recombination, suggesting that the cryptic RNAPII transcription might have a physiological role in regulating rDNA copy number. The Nrd1/Sen1/exosome pathway also contributes to silencing at telomeric loci. These results suggest that silencing of heterochromatic genes in Saccharomyces cerevisiae occurs at both transcriptional and posttranscriptional levels.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available