Voynov Vladimir, Verstrepen Kevin J, Jansen An, Runner Vanessa M, Buratowski Stephen, Fink Gerald R
Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA 02142, USA.
Proc Natl Acad Sci U S A. 2006 Sep 26;103(39):14423-8. doi: 10.1073/pnas.0606546103. Epub 2006 Sep 18.
The evolutionarily conserved multisubunit THO complex, which is recruited to actively transcribed genes, is required for the efficient expression of FLO11 and other yeast genes that have long internal tandem repeats. FLO11 transcription elongation in Tho- mutants is hindered in the region of the tandem repeats, resulting in a loss of function. Moreover, the repeats become genetically unstable in Tho- mutants. A FLO11 gene without the tandem repeats is transcribed equally well in Tho+ or Tho- strains. The Tho- defect in transcription is suppressed by overexpression of topoisomerase I, suggesting that the THO complex functions to rectify aberrant structures that arise during transcription.
进化上保守的多亚基THO复合物被招募到活跃转录的基因上，它是FLO11和其他具有长内部串联重复序列的酵母基因高效表达所必需的。在Tho-突变体中，FLO11转录延伸在串联重复序列区域受到阻碍，导致功能丧失。此外，这些重复序列在Tho-突变体中变得遗传不稳定。没有串联重复序列的FLO11基因在Tho+或Tho-菌株中的转录情况相同。拓扑异构酶I的过表达抑制了Tho-在转录方面的缺陷，这表明THO复合物的功能是纠正转录过程中出现的异常结构。
