tailieunhanh - Báo cáo y học: "RNA polymerase mapping during stress responses reveals widespread nonproductive transcription in yeast"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: RNA polymerase mapping during stress responses reveals widespread nonproductive transcription in yeast. | Kim et al. Genome Biology 2010 11 R75 http 2010 11 7 R75 Genome Biology RESEARCH Open Access RNA polymerase mapping during stress responses reveals widespread nonproductive transeription in yeast Tae Soo Kim1 Chih Long Liu2 6 Moran Yassour3 4 John Holik2 Nir Friedman3 5 Stephen Buratowski1 Oliver J Rando2 Abstract Background The use of genome-wide RNA abundance profiling by microarrays and deep sequencing has spurred a revolution in our understanding of transcriptional control. However changes in mRNA abundance reflect the combined effect of changes in RNA production processing and degradation and thus mRNA levels provide an occluded view of transcriptional regulation. Results To partially disentangle these issues we carry out genome-wide RNA polymerase II PolII localization profiling in budding yeast in two different stress response time courses. While mRNA changes largely reflect changes in transcription there remains a great deal of variation in mRNA levels that is not accounted for by changes in PolII abundance. We find that genes exhibiting excess mRNA produced per PolII are enriched for those with overlapping cryptic transcripts indicating a pervasive role for nonproductive or regulatory transcription in control of gene expression. Finally we characterize changes in PolII localization when PolII is genetically inactivated using the rpb1-1 temperature-sensitive mutation. We find that PolII is lost from chromatin after roughly an hour at the restrictive temperature and that there is a great deal of variability in the rate of PolII loss at different loci. Conclusions Together these results provide a global perspective on the relationship between PolII and mRNA production in budding yeast. Background Gene transcription is one of the major mechanisms by which a cell responds to its environment and the regulation of transcription has been one of the most intensively studied processes in biology over the past half century. In the past decade the .