Mechanisms of small molecule gene transcriptional regulators

总结 通过RhoA和肌动蛋白调节的转录因子的基因转录信号传导在以下方面起关键作用： 多种疾病，如癌症和纤维化。RhoA和肌动蛋白下游转录因子，血清 反应因子（SRF）和肌红蛋白相关转录因子（MRTF）控制细胞增殖、癌细胞 迁移和转移以及肌成纤维细胞活化。我们鉴定了MRTF途径抑制剂化合物， (e.g. CCG-1423和CCG-203971），并且最近鉴定了氧化还原敏感的核蛋白pirin作为一种抗氧化剂。 分子靶这揭示了pirin作为MRTF/SRF和NF κ B调节的基因转录的调节剂 为我们与癌症和纤维化疾病相关的CCG化合物提供新的双重抑制剂机制 通过阻断炎症和促纤维化/增殖信号。 这项工作的总体目标是探索吡林的作用和CCG化合物在 调节基因转录。这个更新应用程序的具体目标是探索pirin对基因的作用 RhoA/MRTF/SRF和NF κ B B调控的转录，并定义pirin依赖性和潜在的pirin- CCG化合物作用的独立分子机制。 为实现这一目标，我们将致力于实现以下具体目标： 目的1从生物化学的角度阐明pirin与MRTF、SRF、p65及其DNA复合物的相互作用， 关于pirin氧化还原状态的作用和pirin调节化合物对这些机制的影响。 目的2探讨吡林在促纤维化和炎症基因表达中的作用及CCG类化合物的作用 转录介导的MRTF/SRF，TGF-β，Toll样受体（TLR），和NF κ B通过使用一种新的pirin敲- 小鼠模型。 影响-这些目标的成功完成将揭示pirin基因调控的机制和范围， 氧化还原环境如何影响这一过程。它还将为未来提供一个机制框架。 开发CCG化合物用于癌症和纤维化疾病的临床用途。

Summary Gene transcription signaling through RhoA- and actin-regulated transcription factors plays a critical role in diverse diseases such as cancer and fibrosis. Transcription factors downstream of RhoA and actin, serum response factor (SRF) and myocardin-related transcription factor (MRTF) controls cell proliferation, cancer cell migration and metastasis and the myofibroblast activation. We identified MRTF-pathway inhibitor compounds (e.g. CCG-1423 and CCG-203971) and recently identified the redox-sensitive nuclear protein pirin as a molecular target. This reveals pirin as a regulator of MRTF/SRF- and NFkB-regulated gene transcription providing a novel dual inhibitor mechanism for our CCG compounds relevant to cancer and fibrotic diseases by blocking both inflammatory and pro-fibrotic/proliferative signals. The overarching goal of this work is to explore the role of pirin and the mechanisms of CCG compounds in regulating gene transcription. The specific goals of this renewal application are to explore pirin’s actions on gene transcription regulated by RhoA/MRTF/SRF and NFB and to define the pirin-dependent and potentially pirin- independent molecular mechanisms of action of the CCG compounds. To accomplish this goal, we will address the following specific aims: Aim 1 Elucidate biochemically, pirin’s interactions with MRTF, SRF, p65, and their DNA complexes with a focus on the role of pirin redox state and the effects of pirin-modulating compounds on these mechanisms. Aim 2 Assess the role of pirin and the effects of CCG compounds in pro-fibrotic and inflammatory gene transcription mediated by MRTF/SRF, TGF-, Toll-like receptors (TLRs), and NFB by use of a novel pirin knock- out mouse model. Impact - Successful completion of these aims will reveal mechanisms and scope of gene regulation by pirin and how this may be influenced by the redox environment. It will also provide a mechanistic framework for future development of CCG compounds for clinical use in cancer and fibrotic diseases.