KY COBRE: MECHANISM OF TRANSCRIPTIONAL CONTROL BY TWO DIABETES GENE PRODUCTS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 基因特异性转录因子通过特异性识别靶基因的启动子区域并介导与辅助调节因子的相互作用来启动转录，以招募主要转录机制的其余部分。大量孟德尔式的人类疾病与这些转录因子编码基因的突变有关，事实上，最近的一项完整的人类基因组分析显示，转录因子代表其种系突变导致各种人类疾病的四个主要蛋白质功能群之一。我们的长期目标是了解这些转录因子调控基因的分子机制，以及在它们中发现的致病突变的分子基础。这个项目的重点是糖尿病。转录因子HNFIα和HNF4cα在器官发育和成人动态平衡中发挥重要作用，已被确定为单基因显性遗传型糖尿病的罪魁祸首基因产物。尽管它们具有相似的生理功能，但它们属于完全不同的转录因子家族，并通过其独特的结构和与不同的协调制子相互作用而具有独特的基因调控机制。关于分子相互作用如何在多复合体形成过程中发生的详细结构信息尚不完全清楚。因此，我们建议(1)解决HNFlcα和HNF4a与其靶DNA和其他功能伙伴形成的复合体中的晶体结构，以及(2)检测导致糖尿病的突变对蛋白质稳定性、DNA结合、体外蛋白质相互作用和体内整体转录活性的影响，以了解基因调控、复合体形成和突变导致功能丧失的分子基础。这些发现将有助于全面了解参与胰岛素作用和分泌的转录调控，并合理靶向这些转录因子，以调节它们的活性，逆转突变带来的不利影响，从而有可能治疗糖尿病。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Gene-specific transcription factors initiate transcription by specifically recognizing promoter regions of the target genes and mediating interactions with coregulators to recruit the remainder of the main transcriptional machinery. A large number of Mendelian human diseases have been linked to the mutations in genes encoding these transcription factors and in fact, a recent complete human genome analysis revealed that transcription factors represent one of the four major functional groups of proteins whose germline mutations result in various human diseases. Our long-term goal is to understand the molecular mechanisms of gene regulation by these transcription factors and the molecular basis of disease-causing mutations found in them. This project focuses on diabetes. The transcription factors HNFI alpha and HNF4c alpha play vital roles in organ development and adult homeostasis, and have been identified as culprit gene products for the monogenic dominant inherited forms of diabetes. Despite their similar physiological roles, they belong to completely different transcription factor families and possess distinctive mechanisms of gene regulation through their unique structures and interactions with different sets of coregulators. Detailed structural information on how the molecular interactions occur during the multicomplex formation is not completely known. Therefore, we propose to (1) solve the crystal structure of HNFlc alpha and HNF4a in complex with its target DNA and other functional partners, and (2) examine the effects of diabetes-causing mutations on protein stability, DNA binding, protein-protein interaction in vitro and overall transcriptional activity in vivo to understand the molecular basis of gene regulation, complex formation and functional loss by mutations. These findings should aid in the overall understanding of transcription control involved in insulin action and secretion, and rational targeting of these transcription factors in order to modulate their activities and reverse the adverse effects by mutations, thus potential treatment for diabetes.