当前位置: X-MOL 学术Plant Cell › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Critical Role of Transcript Cleavage in Arabidopsis RNA Polymerase II Transcriptional Elongation
The Plant Cell ( IF 10.0 ) Pub Date : 2020-03-09
Antosz, W., Deforges, J., Begcy, K., Bruckmann, A., Poirier, Y., Dresselhaus, T., Grasser, K. D.

Transcript elongation factors associate with elongating RNA polymerase II (RNAPII) to control the efficiency of mRNA synthesis and consequently modulate plant growth and development. Encountering obstacles during transcription such as nucleosomes or particular DNA sequences may cause backtracking and transcriptional arrest of RNAPII. The elongation factor TFIIS stimulates the intrinsic transcript cleavage activity of the polymerase, which is required for efficient rescue of backtracked/arrested RNAPII. A TFIIS mutant variant (TFIISmut) lacks the stimulatory activity to promote RNA cleavage, but instead efficiently inhibits unstimulated transcript cleavage by RNAPII. We could not recover viable Arabidopsis tfIIs plants constitutively expressing TFIISmut. Induced, transient expression of TFIISmut in tfIIs plants provoked severe growth defects, transcriptomic changes and massive, transcription-related redistribution of elongating RNAPII within transcribed regions towards the transcriptional start site. The predominant site of RNAPII accumulation overlapped with the +1 nucleosome, suggesting that upon inhibition of RNA cleavage activity RNAPII arrest prevalently occurs at this position. In the presence of TFIISmut, the amount of RNAPII was reduced, which could be reverted by inhibiting the proteasome, indicating proteasomal degradation of arrested RNAPII. Our findings suggest that polymerase backtracking/arrest frequently occurs in plant cells and RNAPII-reactivation is essential for correct transcriptional output and proper growth/development.



中文翻译:

转录切割在拟南芥RNA聚合酶II转录延伸中的关键作用。

转录本延伸因子与延伸RNA聚合酶II(RNAPII)相关联,以控制mRNA合成的效率,从而调节植物的生长发育。在转录过程中遇到障碍,例如核小体或特定的DNA序列,可能会导致RNAPII的回溯和转录停滞。延伸因子TFIIS刺激了聚合酶的内在转录裂解活性,这是有效挽救回溯/被捕的RNAPII所必需的。TFIIS突变体变体(TFIISmut)缺乏促进RNA切割的刺激活性,但有效地抑制了RNAPII对未刺激的转录物的切割。我们无法恢复组成型表达TFIISmut的可行拟南芥tfIIs植物。TFIISmut在tfIIs植物中诱导的瞬时表达引起了严重的生长缺陷,转录区域内转录组的转录组变化和大量转录相关的重新分布,向转录起始位点转移。RNAPII积累的主要位点与+1核小体重叠,这表明在抑制RNA裂解活性后,RNAPII停滞普遍发生在该位置。在TFIISmut的存在下,RNAPII的量减少了,可以通过抑制蛋白酶体来还原,表明蛋白酶体降解了被捕的RNAPII。我们的研究结果表明,聚合酶的回溯/逮捕经常发生在植物细胞中,RNAPII的重新激活对于正确的转录输出和正确的生长/发育至关重要。转录区域内延伸的RNAPII向转录起始位点的转录相关的重新分布。RNAPII积累的主要位点与+1核小体重叠,这表明在抑制RNA裂解活性后,RNAPII停滞普遍发生在该位置。在TFIISmut的存在下,RNAPII的量减少了,可以通过抑制蛋白酶体来还原,表明蛋白酶体降解了被捕的RNAPII。我们的研究结果表明,聚合酶的回溯/逮捕经常发生在植物细胞中,RNAPII的重新激活对于正确的转录输出和正确的生长/发育至关重要。转录区域内延伸的RNAPII向转录起始位点的转录相关的重新分布。RNAPII积累的主要位点与+1核小体重叠,这表明在抑制RNA裂解活性后,RNAPII停滞普遍发生在该位置。在TFIISmut的存在下,RNAPII的量减少了,可以通过抑制蛋白酶体来还原,表明蛋白酶体降解了被捕的RNAPII。我们的研究结果表明,聚合酶的回溯/逮捕经常发生在植物细胞中,RNAPII的重新激活对于正确的转录输出和正确的生长/发育至关重要。提示抑制RNA裂解活性后,RNAPII停滞普遍发生在该位置。在TFIISmut的存在下,RNAPII的量减少了,可以通过抑制蛋白酶体来还原,表明蛋白酶体降解了被捕的RNAPII。我们的研究结果表明,聚合酶的回溯/逮捕经常发生在植物细胞中,RNAPII的重新激活对于正确的转录输出和正确的生长/发育至关重要。提示抑制RNA裂解活性后,RNAPII停滞普遍发生在该位置。在TFIISmut的存在下,RNAPII的量减少了,可以通过抑制蛋白酶体来还原,表明蛋白酶体降解了被捕的RNAPII。我们的研究结果表明,聚合酶的回溯/逮捕经常发生在植物细胞中,RNAPII的重新激活对于正确的转录输出和正确的生长/发育至关重要。

更新日期:2020-04-21
down
wechat
bug