Regulation and Functional Dissection of YAP in Mitosis

YAP 在有丝分裂中的调控和功能解析

• 批准号: 8790759
• 负责人: Jixin Dong
• 金额: $ 28.6万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-10 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8790759
• 关键词: Aneuploidy; Apoptosis; Biological; CDC2 Protein Kinase; Cancer Etiology; Cell Cycle Regulation; Cell Proliferation; Cells; Chromosomal Instability; Chromosome Segregation; Contact Inhibition; Defect; Dissection; Drug Targeting; Ensure; Future; Genomic Instability; Goals; Health; Human Characteristics; Light; Link; Malignant Neoplasms; Mediating; Mitosis; Mitotic; Mitotic Cell Cycle; Molecular; Oncogene Proteins; Oncogenic; Organ; Outcome; Pathway interactions; Phosphorylation; Phosphotransferases; Play; Property; Proteins; Regulation; Role; Signal Pathway; Site; Stem cells; Testing; Tissues; Tumor Suppressor Proteins; Work; base; cancer type; insight; metaplastic cell transformation; mutant; new therapeutic target; novel; overexpression; protein function; self-renewal; therapeutic development; therapeutic target; tumorigenesis

DESCRIPTION (provided by applicant): The Hippo pathway controls cell contact inhibition, stem cell self -renewal, and tumorigenesis through phosphorylating and inactivating the downstream oncoprotein, yes-associated protein (YAP). The PI, along with others, has demonstrated that YAP promotes oncogenesis by stimulating cell proliferation and inhibiting apoptosis. YAP is overexpressed or hyperactivated in many types of cancers. Current studies involving YAP focus on determining its overall oncogenic role in various organs/tissues as well as its role in crosstalk with other signaling pathways. While these studies provide important insight into the oncogenic properties of YAP, however, the underlying molecular mechanisms through which YAP exerts its oncogenic function are poorly understood. The long-term goal of this project is to elucidate the regulatory mechanisms of the Hippo-YAP signaling pathway in mitotic cell-cycle control and oncogenic transformation, thus providing potential therapeutic targets. Our preliminary studies demonstrate that during mitosis YAP is phosphorylated on novel sites and activated in a CDK1-dependent manner. Importantly, mitotic phosphorylation is required for YAP-driven cellular transformation. We have found that YAP is required for the activation of the spindle checkpoint during mitosis. Furthermore, overexpression of YAP, but not of the non - phosphorylatable mutant, hyper-activates the spindle checkpoint and causes mitotic defects. Based on these preliminary studies, we hypothesize that CDK1-mediated mitotic phosphorylation of YAP is biologically significant in the regulation of the spindle checkpoint activation and subsequent oncogenic transformation. Our central hypothesis will be tested through the following three specific aims: Aim 1: Determine the molecular mechanism of YAP regulation/activation during mitosis; Aim 2: Determine the role of YAP and its phosphorylation in mitotic progression, the spindle checkpoint, and aneuploidy; Aim 3: Determine the functional significance of YAP phosphorylation on its targets. Successful completion of these studies will not only reveal novel roles of YAP in mitosis and genome instability, but will also shed light on the mechanisms involved in YAP-driven oncogenesis.

描述（由申请人提供）：Hippo途径通过磷酸化和灭活下游癌蛋白yes相关蛋白（YAP）来控制细胞接触抑制、干细胞自我更新和肿瘤发生。 PI 与其他人一起证明 YAP 通过刺激细胞增殖和抑制细胞凋亡来促进肿瘤发生。 YAP 在许多类型的癌症中过度表达或过度激活。目前涉及 YAP 的研究重点是确定其在各种器官/组织中的总体致癌作用以及其在与其他信号通路串扰中的作用。虽然这些研究为 YAP 的致癌特性提供了重要的见解，但是，人们对 YAP 发挥其致癌功能的潜在分子机制知之甚少。该项目的长期目标是阐明Hippo-YAP信号通路在有丝分裂细胞周期控制和致癌转化中的调控机制，从而提供潜在的治疗靶点。我们的初步研究表明，在有丝分裂期间，YAP 在新位点上被磷酸化，并以 CDK1 依赖性方式激活。重要的是，有丝分裂磷酸化是 YAP 驱动的细胞转化所必需的。我们发现 YAP 是有丝分裂期间纺锤体检查点激活所必需的。此外，YAP 的过度表达（而非不可磷酸化突变体的过度表达）会过度激活纺锤体检查点并导致有丝分裂缺陷。基于这些初步研究，我们假设 CDK1 介导的 YAP 有丝分裂磷酸化在调节纺锤体检查点激活和随后的致癌转化中具有生物学意义。我们的中心假设将通过以下三个具体目标进行检验： 目标 1：确定有丝分裂过程中 YAP 调节/激活的分子机制；目标 2：确定 YAP 及其磷酸化在有丝分裂进展、纺锤体检查点和非整倍性中的作用；目标 3：确定 YAP 磷酸化对其靶标的功能意义。这些研究的成功完成不仅将揭示 YAP 在有丝分裂和基因组不稳定中的新作用，还将揭示 YAP 驱动的肿瘤发生的机制。