TRANSCRIPTION COFACTORS OF THE THYROID HORMONE RECEPTOR

描述（改编自申请人摘要）：长期 该提案的既定目标是了解辅助因素如何 通过甲状腺激素受体调节转录调节 （TR）。这位研究者分离出了一组独特的新蛋白质 甲状腺受体相关蛋白（thyroid receptor associated proteins）体外 转录测定显示TR-TRAP复合物显著激活 从含有TR结合位点的启动子模板转录。他 克隆了其中一个TRAP（TRAP 220），发现它直接与 在体内以T3依赖的方式与TR结合。这种蛋白质 与PBP具有显著的序列同源性，PBP是一种推定的 过氧化物酶体增殖物激活受体（PPARs）和RB18A，一种新的 p53样共调节蛋白。研究者假设TRAP 220单独或与其他TRAP子单元一起，充当一个或多个TRAP子单元。 基因特异性转录的正辅激活因子。的目标 建议是：（1）根据配体表征TRAP 220功能- 诱导与TR和其他核激素受体（NR）的相互作用 使用缺失和定点诱变来确定相互作用 TRAP 220和其他NR的基序使用各种蛋白质-蛋白质 相互作用研究和DNA迁移率变动测定。(2)检查 TRAP 220作为转录共激活因子的功能相关性 TR和其他NR在共转染中的依赖性激活 测定和体外转录分析。(3)识别特定 在物理上和功能上与TRAP 220相互作用的辅因子。他 建议使用远西方分析来筛选TR-TRAP复合体 TRAP 220作为鉴定TRAP 220相互作用因子的探针， 最近克隆的TRAP亚基将筛选TRAP 220 使用蛋白质-蛋白质相互作用测定进行相互作用。识别 将进一步测定辅因子的体内和功能 与陷阱220的联系。

DESCRIPTION (Adapted from the applicant's abstract): The long-term stated goal of this proposal is to understand how auxiliary factors modulate transcriptional regulation by the thyroid hormone receptor (TR). This investigator has isolated a distinct group of novel proteins termed TRAPs (thyroid receptor associated proteins). In vitro transcription assays showed that the TR-TRAP complex markedly activates transcription from promoter templates containing TR-binding sites. He has cloned one of the TRAPs (TRAP 220) and found it directly interacts with TR in vivo in a T3-dependent manner. This protein shares significant sequence homology with PBP, a putative co-activator of peroxisome proliferator-activated receptors (PPARs), and RB18A, a novel p53-like co-regulatory protein. The investigator hypothesizes that TRAP 220, alone or in concert with other TRAP subunits, functions as a positive co-activator for gene-specific transcription. The aims of the proposal are: (1) Characterize TRAP 220 function in terms of ligand- induced interactions with TR and other nuclear hormone receptors (NRs) using deletion and site-directed mutagenesis to define interaction motifs of both TRAP 220 and other NRs using various protein-protein interaction studies and DNA mobility shift assays. (2) Examine the functional relevance of TRAP 220 as a transcriptional co-activator for hormone-dependent activation by TR and other NRs in co-transfection assays and in vitro transcription analyses. (3) Identify the specific cofactors which physically and functionally interact with TRAP 220. He proposes to screen the TR-TRAP complex by far western analysis using TRAP 220 as a probe to identify TRAP 220-interacting factors and a panel of recently cloned TRAP subunits will be screened for TRAP 220 interactions using protein-protein interaction assays. Identified cofactors will be further assayed for in vivo and functional associations with TRAP 220.