Elucidation of Integrator's Function

 描述（由申请人提供） 整合子是与RNA聚合酶II（RNAPII）的C-末端结构域（CTD）稳定缔合的多蛋白复合物。整合子含有一个催化RNA内切酶亚基（INTS 11），与切割和多聚腺苷酸化特异性因子73（CPSF 73）具有高度同源性，CPSF 73是负责信使RNA（mRNA）基因切割和终止的酶。我们发现整合子占据小核RNA基因（snRNA），并且其催化活性是这些非多聚腺苷酸化转录物的3 '端加工所需的。在此期间，我们扩大了我们的功能研究，以揭示Integrator在蛋白质编码基因和远端增强子中的作用。在所提出的研究中，我们打算通过以下具体目标阐明整合子在增强子及其各自的蛋白质编码启动子处的潜在分子机制：目的1）我们将研究整合子调节蛋白质编码基因处的转录延伸（RNAPII暂停释放）的分子机制。目的2）阐明整合子在增强子RNA生物合成和增强子功能中的作用。目的3）我们将阐明整合子与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.