Elucidation of Integrator's Function

 描述(由申请人提供) 整合子是一种与RNA聚合酶II(RNAPII)的C末端结构域(CTD)稳定相关的多蛋白质复合体。整合子含有一个催化RNA内切酶亚单位(INTS11)，与切割和多聚腺苷酸化特异性因子73(CPSF73)高度同源，CPSF73是负责切割和终止信使RNA(MRNA)基因的酶。我们发现，整合子占据了小核RNA基因(SnRNA)，并且它的催化活性是这些非多腺苷化转录本的3‘端加工所必需的。在这笔赠款资助的过程中，我们扩大了我们的功能研究，以揭示整合子在蛋白质编码基因和远端增强子中的作用。在拟议的研究中，我们打算通过以下特定目的来阐明整合子在增强子及其各自的蛋白质编码启动子中作用的分子机制：1)我们将研究整合子调节蛋白质编码基因转录延长(RNAPII暂停释放)的分子机制。目的2)阐明整合子在增强子RNA生物发生和增强子功能中的作用。目的3)我们将探讨整合子和CTD不同磷酸化状态在转录激活调控中的物理和功能联系。

 DESCRIPTION (provided by applicant) Integrator is a multi-protein complex stably associated with the C-terminal domain (CTD) of RNA polymerase II (RNAPII). Integrator contains a catalytic RNA endonuclease subunit (INTS11) with high degree of homology to cleavage and polyadenylation specificity factor 73 (CPSF73), the enzyme responsible for cleavage and termination of messenger RNA (mRNA) genes. We showed that Integrator occupies the small nuclear RNA genes (snRNA) and that its catalytic activity was required for the 3'-end processing of these non- polyadenylated transcripts. We have expanded our functional studies during the course of this grant funding to uncover a role for Integrator at protein-coding genes and distal enhancers. In the proposed studies we intend to illuminate the molecular mechanism underlying Integrator function at enhancers and their respective protein-coding promoters through the following specific aims: Aim1) We will investigate the molecular mechanisms by which Integrator regulates transcriptional elongation (RNAPII pause release) at protein-coding genes. Aim 2) We will elucidate the role of Integrator in enhancer RNA biogenesis and enhancer function. Aim 3) We will address the physical and functional association of Integrator and different phosphorylation states of the CTD in regulation of transcriptional activation.