The Ras/PKA signaling pathway may control RNA polymerase II elongation via the Spt4p/Spt5p complex in Saccharomyces cerevisiae.
The Ras/PKA signaling pathway may control RNA polymerase II elongation via the Spt4p/Spt5p complex in Saccharomyces cerevisiae.
复制标题
Ras/PKA 信号通路可能通过酿酒酵母中的 Spt4p/Spt5p 复合物控制 RNA 聚合酶 II 延伸。
DOI：
10.1093/genetics/165.3.1059
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发表时间：
2003
期刊：
影响因子：
3.3
通讯作者：
Herman,PaulK
中科院分区：
文献类型：
--
作者：
Howard,SusieC;Hester,Arelis;Herman,PaulK
The Ras signaling pathway inSaccharomyces cerevisiaecontrols cell growth via the cAMP-dependent protein kinase, PKA. Recent work has indicated that these effects on growth are due, in part, to the regulation of activities associated with the C-terminal domain (CTD) of the largest subunit of RNA polymerase II. However, the precise target of these Ras effects has remained unknown. This study suggests that Ras/PKA activity regulates the elongation step of the RNA polymerase II transcription process. Several lines of evidence indicate that Spt5p in the Spt4p/Spt5p elongation factor is the likely target of this control. First, the growth ofspt4andspt5mutants was found to be very sensitive to changes in Ras/PKA signaling activity. Second, mutants with elevated levels of Ras activity shared a number of specific phenotypes withspt5mutants and vice versa. Finally, Spt5p was efficiently phosphorylated by PKAin vitro. Altogether, the data suggest that the Ras/PKA pathway might be directly targeting a component of the elongating polymerase complex and that this regulation is important for the normal control of yeast cell growth. These data point out the interesting possibility that signal transduction pathways might directly influence the elongation step of RNA polymerase II transcription.
