Abstract
Dr1 (also known as NC2β) was identified as a repressor of RNA polymerase (pol) II transcription. It was subsequently shown to inhibit pol III transcription when expressed at high levels in vitro or in yeast cells. However, endogenous Dr1 was not detected at pol III-transcribed genes in growing yeast. In contrast, we demonstrate that endogenous Dr1 is present at pol III templates in human cells, as is its dimerization partner DRAP1 (also called NC2α). Expression of tRNA by pol III is selectively enhanced by RNAi-mediated depletion of endogenous human Dr1, but we found no evidence that DRAP1 influences pol III output in vivo. A stable association was detected between endogenous Dr1 and the pol III-specific transcription factor Brf1. This interaction may recruit Dr1 to pol III templates in vivo, as crosslinking to these sites increases following Brf1 induction. On the basis of these data, we conclude that the physiological functions of human Dr1 include regulation of pol III transcription.
| Original language | English |
|---|---|
| Pages (from-to) | 1228-1239 |
| Number of pages | 12 |
| Journal | Nucleic Acids Research |
| Volume | 38 |
| Issue number | 4 |
| Early online date | 3 Dec 2009 |
| DOIs | |
| Publication status | Published - 4 Mar 2010 |
Keywords
- Animals
- Cricetulus
- Humans
- RNA Polymerase III
- Transcription Factor TFIIIB
- Transcription, Genetic
- RNA, Transfer
- Transcription Factors
- Phosphoproteins
- Repressor Proteins
- CHO Cells
- Gene Expression Regulation
- RNA Interference
- Cell Line
- Cricetinae