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

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 所有细胞都通过改变基因表达模式来应对环境波动。真核生物的基因调控始于转录的启动，并通过信使RNA的输出和翻译而持续。在酿酒酵母中，对氨基酸的饥饿会产生一个信号，导致转录激活蛋白Gcn4p的增加。Gcn4p调控超过500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产生自己的氨基酸。Gcn4p激活基因的机制已经得到了很好的研究，但目前还不清楚这些基因在饥饿条件解除后是如何被抑制的。Gcn4p需要CCR4-NOT共激活子复合体才能完全表达靶基因。然而，CCR4-NOT也具有破坏mRNAs的活性。我们最近的研究结果表明，CCR4-NOT在转录后参与了Gcn4p控制下的基因调控。本研究的目的是确定CCR4-Not在Gcn4p靶基因表达中的确切转录后作用(S)。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. 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.