RNA POL II POLY-A SITE AND 3' TERMINATION

调节mRNA群体的能力是正常细胞的关键因素， 细胞周期调节、细胞分化和细胞增殖所需的功能 保持战略定力 微小的mRNA变化可以对细胞产生重大影响。 功能，可能最好的代表是改变的癌基因的影响， 表达或激素诱导。 显然，启动子激活受 启动和抑制功能都是mRNA中的主要参与者， 代谢，但它不是mRNA群体可以被代谢的唯一水平。 控制。 越来越多的转录单位也在 “后启动”控制功能的影响，包括过早 终止（c-myc，c-myb，Ad-mlp），可变剪接和可变剪接 多聚腺苷酸化（Ad-mlp、降钙素/CGRP、肌肉蛋白）和 转录终止（IG μ-δ，Ad-mlp. 除了这些 核事件，在细胞质中特异性控制mRNA的1/2寿命， 也变得越来越明显。 一个人的“后启蒙”规则 细胞mRNA群体是我的研究小组的一般研究领域， 寻址。 本建议专门涉及旨在 了解调节其中两个事件的机制， 复杂转录单位中poly（A）选择与RNA终止 聚合酶II转录单位。 一个重要方面的后启动功能，目前是开放的， 争论的焦点是，这些事件的调节是否是直接介导的， 通过RNA聚合酶II延伸复合物，或者这些事件 （特别是剪接和多聚腺苷酸化）控制在一个点， 从转录复合物中解偶联。 这个问题也很重要， 转录终止的控制，因为我们已经证明了 DNA序列AATAAA（多聚腺苷酸化信号序列）是必需的顺式 3、“终止”。 这份提案直接回答了这一点 合成（使用重建的腺病毒载体）和体外解剖 参与控制3' postinitiation的生化过程 事件 这些研究将产生的基本信息将 包括体内和体外聚（A）位点利用率比较， 几个多聚腺苷酸化信号元件，与poly（A）的效率相关， 转录终止的位点利用，鉴定3'共有序列 诱导转录复合物置换所需的序列， 最后，演示腺病毒主要晚期转录单位， 在MLP处产生不同的预引发复合物可以影响 在3'末端的延伸和加工事件。

The ability to regulate the mRNA population is a key element of normal cell function, required for cell cycle regulation, cell differentiation and cell determination. Minor mRNA changes can have a major impact on cell function, possibly best represented by the effects of altered oncogene expression or hormone induction. Clearly, promoter activation effected by both initiation and repression functions is a dominant player in mRNA metabolism, but it is not the only level at which mRNA populations can be controlled. A growing number of transcription units are also under the influence of "postinitiation" control functions which include premature termination (c-myc, c-myb, Ad-mlp), alternative splicing and alternative polyadenylation (Ad-mlp, calcitonin/CGRP, muscle proteins) and transcription termination (Ig mu-delta, Ad-mlp. In addition to these nuclear events, in the cytoplasm cell specific control of mRNA 1/2 life is also becoming more and more apparent. The "postinitiation" regulation of a cells mRNA population is the general area of research my group is addressing. This proposal deals specifically with experiments designed to understand the mechanisms which operate to regulate two of these events, poly(A) choice in complex transcription units and termination of RNA polymerase II transcription units. One important aspect of postinitiation functions which is presently open to debate is whether the regulation of these events is mediated directly through the RNA polymerase II elongation complex or are these events (particularly splicing and polyadenylation) controlled at a point which is uncoupled from the transcription complex. This issue is also important to the control of transcription termination, since we have demonstrated the DNA sequence AATAAA (polyadenylation signal sequence) is a required cis element of 3' termination. This proposal is directly answering this synthesis (using reconstructed adenovirus vectors) and in vitro dissection of the biochemical process involved in controlling the 3' postinitiation events. Basic information which will be generated by these studies will include comparison of in vivo and in vitro poly (A) site utilization for several polyadenylation signal elements, relate the efficiency of poly (A) site utilization to transcription termination, identify the 3' consensus sequence required to inducer transcription complex displacement and finally, demonstrate how for the adenovirus major late transcription unit, the generation of varied preinitiation complexes at the mlp can influence elongation and processing events at the 3' end.