CCR4-NOT CO-ACTIVATOR'S POST-TRANSCRIPTION FUNCTIONS

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 所有细胞都通过改变基因表达模式来应对环境波动。真核生物中的基因调控始于转录起始，并通过信使RNA的输出和翻译继续。在酿酒酵母中，氨基酸饥饿产生导致Gcn 4p（一种转录激活蛋白）增加的信号。gcn 4p调控500多个基因，包括那些参与氨基酸生物合成的基因。因此，不能从环境中获得氨基酸的酵母细胞会产生自己的氨基酸。Gcn 4p的基因激活机制已经得到了很好的研究，但目前还不清楚这些基因是如何被抑制后，饥饿条件被解除。Gcn 4p需要CCR 4-NOT共激活因子复合物以实现完整的靶基因表达。然而，CCR 4-NOT也具有破坏mRNA的活性。我们最近的研究结果表明，CCR 4-NOT在转录后调控Gcn 4p控制的基因。本研究的目的是确定CCR 4-NOT在Gcn 4p靶基因表达中的确切转录后作用。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. All cells respond environmental fluctuations by altering patterns of gene expression. Gene regulation in eukaryotes begins at initiation of transcription and continues through export and translation of messenger RNAs. In the yeast Saccharomyces cerevisiae, starvation for amino acids generates a signal leading to an increase in Gcn4p, a transcriptional activator protein. Gcn4p regulates over 500 genes, including those involved in amino acid biosynthesis. Thus, yeast cells that cannot obtain amino acids from their environment produce their own. Mechanisms of gene activation by Gcn4p have been well studied, but it is not clear how these genes are repressed after starvation conditions are relieved. Gcn4p requires the CCR4-NOT co-activator complex for full target gene expression. However, CCR4-NOT also possesses activities for the destruction of mRNAs. Our recent results indicate that CCR4-NOT plays in regulating genes under Gcn4p control after transcription. The goal of this research is to determine the exact post-transcriptional role(s) of CCR4-NOT in Gcn4p target gene expression.