Regulation of myogenic transcription by the Paf1C complex

选择性切割和多聚腺苷酸化位点（阿帕）的使用正在成为一个关键的基因调控机制， 机制，并且已知其在增殖和发育中发挥重要作用。最近的研究 显示3'非翻译区（UTR）延长发生在哺乳动物胚胎发育期间， 骨骼肌分化通过选择性多聚腺苷酸化发生延长，尽管 调节这一过程的机制尚未完全了解。此外，连接的机制 切割和多腺苷酸化至RNA聚合酶II（PolII）终止还不清楚。我们有 研究了这些关键转录机制的基础，重点是PAF复合物（Paf1C）， 哺乳动物的肌肉细胞Paf1C作为一个平台，在会议期间协调众多活动， 转录周期，从转录延伸到3'末端加工。我们的综合研究显示 Paf1C在抑制交替的多聚腺苷酸化（PA）位点以及上游和基因内的新作用 反义转录该提案将利用调查人员的互补专业知识， 结合最先进的基因组学，计算生物学和生物化学，严格调查 Paf1C复合物在转录物加工和选择性多聚腺苷酸化中的作用，测试这些作用 肌源性分化的关键事件。在两个目标中，我们将探索潜在的物理和功能 Paf1C和3'端加工因子之间的联系，染色质修饰，PolII进展，以及 调节PA的使用，我们将把它们的协调活动的背景下，肌分化。 我们将确定Paf1C如何抑制上游反义转录和近端pA的使用， 研究切割和多聚腺苷酸化因子的潜在参与。最后，我们将确定是否 Paf1C通过抑制基因间和基因内转录发挥监视功能， 与另一个延伸因子的相互作用。总之，这些研究将试图整合不同的角色， Paf1C在染色质修饰中的作用及对交替多聚腺苷酸化、通读和反义的调节 转录和肌源性分化的基因表达的变化。更广泛地说，我们的研究 将揭示Paf1C在基因组监视中的作用，该基因组监视调节lncRNA的产生和抑制 反义转录我们的研究与人类健康有关，因为在一个基因组中， Paf1C成分导致甲状旁腺肿瘤，切割和多聚腺苷酸化因子的突变导致甲状旁腺肿瘤。 肌肉萎缩症的类型。因此，我们的建议将有助于对基本的新见解， 转录机制以及关于人类疾病的潜在重要信息。

Usage of alternative cleavage and polyadenylation sites (APA) is emerging as a critical gene regulatory mechanism, and it is known to play important roles in proliferation and development. Recent studies have shown that 3’ untranslated region (UTR) lengthening occurs during mammalian embryonic development and skeletal muscle differentiation. Lengthening occurs through alternative polyadenylation, although the mechanisms that regulate this process are not completely understood. Furthermore, the mechanisms that link cleavage and polyadenylation to RNA polymerase II (PolII) termination are not well understood. We have investigated the basis for these key transcriptional mechanisms by focusing on the PAF complex (Paf1C) in mammalian muscle cells. Paf1C acts as a platform to orchestrate a multitude of activities during the transcription cycle, from transcriptional elongation to 3’ end processing. Our combined studies have revealed novel roles for Paf1C in suppression of alternate polyadenylation (pA) sites as well as upstream and intragenic antisense transcription. This proposal will leverage the complementary expertise of investigators who will use a combination of state-of-the-art genomics, computational biology, and biochemistry to rigorously investigate the role of the Paf1C complex in transcript processing and alternative polyadenylation, testing the role of these critical events in myogenic differentiation. In two aims, we will explore potential physical and functional connections between Paf1C and 3’ end processing factors, chromatin modifications, PolII progression, and regulation of pA usage, and we will place their coordinated activities in the context of myogenic differentiation. We will determine how Paf1C suppresses upstream anti-sense transcription and proximal pA usage, investigating potential involvement of cleavage and polyadenylation factors. Lastly, we will determine whether Paf1C serves a surveillance function by suppressing intergenic and intragenic transcription through interactions with another elongation factor. Altogether, these studies will attempt to integrate diverse roles for Paf1C in chromatin modifications with regulation of alternative polyadenylation, readthrough and antisense transcription, and changes in gene expression underlying myogenic differentiation. More broadly, our studies will reveal roles for Paf1C in genome surveillance that regulate production of lncRNAs and suppression of antisense transcription. Our studies are relevant to human health because loss of function mutations in a Paf1C component lead to parathyroid tumors, and mutations in a cleavage and polyadenylation factor lead to a type of muscular dystrophy. Thus, our proposal will contribute fundamental new insights into basic transcriptional mechanisms as well as potentially important information regarding human disease.