Role of H11 kinase in cardiac cell growth

H11 激酶在心肌细胞生长中的作用

• 批准号: 6731689
• 负责人: Christophe Depre
• 金额: $ 37.49万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-12-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6731689
• 关键词: cardiac myocytes; cardiogenesis; cell growth regulation; genetically modified animals; heat shock proteins; laboratory mouse; laboratory rat; myocardial ischemia /hypoxia; protein kinase; protein protein interaction; reperfusion; tissue /cell culture

DESCRIPTION (provided by applicant): H11 kinase is the eukaryotic homologue of ICP10 protein kinase, a Ras-GAP kinase from Herpes Simplex required for virus growth. In normal tissues, H11 kinase expression is restricted to the heart and skeletal muscle. Although its function remains unknown, H11 kinase probably participates in mechanisms of cell growth because its induction in non-muscular cells promotes transformation into cancer cells. Putative interactions include the nuclear casein kinase II (NUCKS II), a stimulator of cell growth, the protein HSP27, a stimulator of cell survival, and the nucleosome assembly protein-1 (NAP-l), a stimulator of cell proliferation. By subtractive hybridization, we unexpectedly found that H11 kinase transcript and protein are upregulated in large mammalian models of reversible ischemia/reperfusion and chronic left ventricular hypertrophy. Our preliminary data show that overexpression of H11 kinase in isolated cardiac myocytes promotes cell growth. A cardiac-specific transgenic mouse has been generated, which confirms that overexpression of H11 kinase induces cardiac hypertrophy and protects against cell death during ischemia/reperfusion in vivo. Based on these observations, the overall goal of this proposal is to determine the physiological role, signaling mechanisms and functional importance of H11 kinase in the myocardium. The first specific aim is to determine in vivo the functional and genomic effects of H11 kinase overexpression in a cardiac-specific transgenic mouse model submitted to transverse aortic banding or ischemia/reperfusion. We hypothesize that H11 kinase overexpression in transgenic mice will decrease irreversible cellular damage in hypertrophied and ischemic hearts. The second aim is to determine the signaling pathways in which H11 kinase is integrated. We hypothesize that H11 kinase promotes cardiac growth and survival by stimulating NUCKS II, HSP27 and NAP-l, but that other unexpected proteins might interact as well. The third aim is to show, both in vitro with a dominant negative and in vivo in a knock-out model, that H11 kinase represents an essential pathway of cardiac growth and survival. We hypothesize that the tissue-restricted expression of H11 kinase underlies a specific signaling pathway that is not dispensable for normal cardiac cell growth. These experiments will unravel novel mechanisms and signaling pathways of cardiac growth, which may result in new therapeutic avenues for both ischemic heart disease and heart failure.

描述（由申请人提供）：H11 激酶是 ICP10 蛋白激酶的真核同源物，ICP10 蛋白激酶是病毒生长所需的来自单纯疱疹的 Ras-GAP 激酶。在正常组织中，H11 激酶表达仅限于心脏和骨骼肌。尽管其功能尚不清楚，但 H11 激酶可能参与细胞生长机制，因为它在非肌肉细胞中的诱导会促进向癌细胞的转化。假定的相互作用包括细胞生长刺激剂核酪蛋白激酶 II (NUCKS II)、细胞存活刺激剂蛋白 HSP27 和细胞增殖刺激剂核小体组装蛋白 1 (NAP-1)。通过消减杂交，我们意外地发现H11激酶转录物和蛋白在可逆性缺血/再灌注和慢性左心室肥大的大型哺乳动物模型中上调。我们的初步数据表明，H11 激酶在分离的心肌细胞中过度表达可促进细胞生长。心脏特异性转基因小鼠的诞生，证实了 H11 激酶的过度表达可诱导心脏肥大，并在体内缺血/再灌注期间防止细胞死亡。基于这些观察，该提案的总体目标是确定 H11 激酶在心肌中的生理作用、信号传导机制和功能重要性。第一个具体目标是确定 H11 激酶过表达在心脏特异性转基因小鼠模型中的体内功能和基因组效应，该小鼠模型经历主动脉横带或缺血/再灌注。我们假设转基因小鼠中 H11 激酶过度表达将减少肥大和缺血心脏中不可逆的细胞损伤。第二个目标是确定 H11 激酶整合的信号传导途径。我们假设 H11 激酶通过刺激 NUCKS II、HSP27 和 NAP-1 来促进心脏生长和存活，但其他意想不到的蛋白质也可能相互作用。第三个目标是在体外显性失活模型和体内敲除模型中证明 H11 激酶代表心脏生长和存活的重要途径。我们假设 H11 激酶的组织限制性表达是正常心肌细胞生长不可或缺的特定信号传导途径的基础。这些实验将揭示心脏生长的新机制和信号通路，这可能为缺血性心脏病和心力衰竭带来新的治疗途径。