Defining the Influence of the A12.2 Subunit on Transcription Elongation and Termination by RNA Polymerase I In Vivo.
Defining the Influence of the A12.2 Subunit on Transcription Elongation and Termination by RNA Polymerase I In Vivo.
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DOI：
10.3390/genes12121939
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发表时间：
2021-11-30
期刊：
影响因子：
3.5
通讯作者：
Schneider DA
中科院分区：
文献类型：
--
作者：
Clarke AM;Huffines AK;Edwards YJK;Petit CM;Schneider DA
酿酒酵母具有大约200个拷贝的35S rDNA基因，串联排列在染色体XII上。该基因由RNA聚合酶I（Pol I）转录，35S rRNA转录物被加工以产生核糖体生物合成所需的四种rRNA中的三种。基因间间隔区（IGS）将35S基因的每个拷贝分开，并包含5S rDNA基因、DNA复制起点和相邻35S基因的启动子。Pol I是一种14亚基酶，负责大部分rRNA合成，从而维持正常的细胞功能和生长。Pol I的A12.2亚基在转录过程中的切割、终止和核苷酸添加中起着至关重要的作用。该亚基的缺失导致核苷酸添加动力学的改变和转录终止位点的通读。为了探究这两种现象，我们用S.酿酒酵母中，并评估了跨35S基因和IGS的Pol I占据的所得变化。与野生型（WT）相比，我们观察到整个35S基因的Pol I占用率的模板序列特异性变化。我们还观察到rpa12Δ Pol I在两个终止位点下游和大部分IGS（包括5S基因）中的占有率。rpa12Δ Pol I的相对占有率在启动子近端Reb 1结合位点上游增加，下游显著下降，暗示该位点是Pol I转录的第三个终止子。总的来说，这些高分辨率的结果表明，A12.2亚基的Pol I在转录延伸和终止中起着重要的作用。
Saccharomyces cerevisiae has approximately 200 copies of the 35S rDNA gene, arranged tandemly on chromosome XII. This gene is transcribed by RNA polymerase I (Pol I) and the 35S rRNA transcript is processed to produce three of the four rRNAs required for ribosome biogenesis. An intergenic spacer (IGS) separates each copy of the 35S gene and contains the 5S rDNA gene, the origin of DNA replication, and the promoter for the adjacent 35S gene. Pol I is a 14-subunit enzyme responsible for the majority of rRNA synthesis, thereby sustaining normal cellular function and growth. The A12.2 subunit of Pol I plays a crucial role in cleavage, termination, and nucleotide addition during transcription. Deletion of this subunit causes alteration of nucleotide addition kinetics and read-through of transcription termination sites. To interrogate both of these phenomena, we performed native elongating transcript sequencing (NET-seq) with an rpa12Δ strain of S. cerevisiae and evaluated the resultant change in Pol I occupancy across the 35S gene and the IGS. Compared to wild-type (WT), we observed template sequence-specific changes in Pol I occupancy throughout the 35S gene. We also observed rpa12Δ Pol I occupancy downstream of both termination sites and throughout most of the IGS, including the 5S gene. Relative occupancy of rpa12Δ Pol I increased upstream of the promoter-proximal Reb1 binding site and dropped significantly downstream, implicating this site as a third terminator for Pol I transcription. Collectively, these high-resolution results indicate that the A12.2 subunit of Pol I plays an important role in transcription elongation and termination.
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影响因子：
3
作者：
Nettling M;Treutler H;Grau J;Keilwagen J;Posch S;Grosse I
通讯作者：
Grosse I
影响因子：
10.5
作者：
El Hage, Aziz;Koper, Michal;Tollervey, David
通讯作者：
Tollervey, David
影响因子：
64.5
作者：
Hartley PD;Madhani HD
通讯作者：
Madhani HD
影响因子：
5.3
作者：
LANG, WH;REEDER, RH
通讯作者：
REEDER, RH
DOI：
10.1073/pnas.0401393101
发表时间：
2004-04-20
影响因子：
11.1
作者：
Prescott, EM;Osheim, YN;Proudfoot, NJ
通讯作者：
Proudfoot, NJ