TAT ASSOCIATED KINASE REGULATION OF HIV GENE EXPRESSION

描述：（改编自研究者摘要）达特刺激基因 通过增加RNA聚合酶II有效表达的能力， 经历转录延伸。 最近的研究表明， 结合磷酸化C-末端结构域（CTD）的细胞激酶 RNA聚合酶II。 研究者已经纯化了激酶复合物， 证明了它含有新的成分， 多蛋白质转录因子TF II H的特征组分。 野生型，而不是突变体达特蛋白，大大增强了细胞的能力， 激酶复合物磷酸化RNA聚合酶II CTD，并添加 激酶与HIV-1 LTR的体外转录测定显著相关， 刺激达特活化，表明tat相关激酶复合物 一种参与HIV-1达特激活的关键细胞因子。 的 调查员建议研究达特组织与 激酶复合物增加HIV-1基因表达。 具体目标包括： 确定激酶复合物的哪些细胞组分能够 直接与达特联系。 测定新组分的功能 使用体外和体内测定来测定TAT相关复合物。 确定 达特是否促进激酶复合物与RNA的结合 聚合酶II和达特是否改变TF II H的酶活性。 建立一个重组的体外转录系统达特 激活依赖于Tat相关激酶的加入， 进一步确定该激酶在体内调节HIV-1中的作用 基因表达。

DESCRIPTION: (Adapted From Investigator's Abstract) Tat stimulates gene expression by increasing the ability of RNA polymerase II to efficiently undergo transcriptional elongation. Recent studies suggest that tat can bind a cellular kinase that phosphorylates the C-terminal domain (CTD) of RNA polymerase II. The investigator has purified the kinase complex and demonstrated that it contains novel components as well as previously characterized components of the multi-protein transcription factor, TF II H. Wildtype, but not mutant tat proteins, greatly enhance the ability of the kinase complex to phosphorylate the RNA polymerase II CTD and addition of the kinase to in vitro transcription assays with the HIV-1 LTR markedly stimulated tat activation, suggesting that tat-associated kinase complex is a critical cellular factor involved in tat activation of HIV-1. The investigator proposes to examine the mechanism by which tat association with a kinase complex increases HIV-1 gene expression. Specific aims include: Determine which cellular components of the kinase complex are able to directly associate with tat. Assay the function of novel components of the tat-associated complex using both in vitro and in vivo assays. Determine whether tat facilitates association of the kinase complex with RNA polymerase II and whether tat alters enzymatic activities of TF II H. Develop a reconstituted in vitro transcription system in which tat activation is dependent on the addition of the tat-associated kinase and further to determine the role of this kinase on regulating in vivo HIV-1 gene expression.