Dephosphorylation and genome-wide association of Maf1 with Pol III-transcribed genes during repression
Dephosphorylation and genome-wide association of Maf1 with Pol III-transcribed genes during repression
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DOI：
10.1016/j.molcel.2006.04.009
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发表时间：
2006-06-09
期刊：
影响因子：
16
通讯作者：
Cairns, Bradley R.
中科院分区：
文献类型：
--
作者：
Roberts, Douglas N.;Wilson, Boris;Cairns, Bradley R.
营养缺乏和各种胁迫条件抑制RNA聚合酶III（Pol III）的转录。啤酒。传递压力和营养条件的信号传导途径集中在保守的蛋白Maf 1上，但Maf 1如何整合环境条件并将其与转录抑制偶联在很大程度上是未知的。在这里，我们证明，Maf 1是磷酸化的有利条件下，而不同的不利条件导致快速Maf 1去磷酸化，核定位，物理协会的去磷酸化Maf 1与Pol III，Maf 1靶向Pol III转录基因全基因组。此外，Maf 1突变体缺陷的完全去磷酸化显示maf 1 Delta表型和妥协的核定位和Pol III协会。抑制条件也促进交联染色质中的TFIIIB-TFIIIC相互作用。两者合计，Maf 1似乎通过其磷酸化状态整合环境条件和信号传导途径，应激导致去磷酸化，与靶位点的Pol III相关，基础因子相互作用的改变和转录抑制。
Nutrient deprivation and various stress conditions repress RNA polymerase III (Pol III) transcription in S. cerevisiae. The signaling pathways that relay stress and nutrient conditions converge on the conserved protein Maf1, but how Maf1 integrates environmental conditions and couples them to transcriptional repression is largely unknown. Here, we demonstrate that Maf1 is phosphorylated in favorable conditions, whereas diverse unfavorable conditions lead to rapid Maf1 dephosphorylation, nuclear localization, physical association of dephosphorylated Maf1 with Pol III, and Maf1 targeting to Pol III-transcribed genes genome wide. Furthermore, Maf1 mutants defective in full dephosphorylation display maf1 Delta phenotypes and are compromised for both nuclear localization and Pol III association. Repression conditions also promote TFIIIB-TFIIIC interactions in crosslinked chromatin. Taken together, Maf1 appears to integrate environmental conditions and signaling pathways through its phosphorylation state, with stress leading to dephosphorylation, association with Pol III at target loci, alterations in basal factor interactions, and transcriptional repression.