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(申请人提供)：H11激酶是ICP10蛋白激酶的真核同源物，ICP10是单纯疱疹病毒生长所需的RAS-GAP激酶。在正常组织中，H11蛋白的表达仅限于心脏和骨骼肌。虽然H11的功能尚不清楚，但它可能参与了细胞生长的机制，因为它在非肌肉细胞中的诱导促进了向癌细胞的转化。可能的相互作用包括核酪蛋白激酶II(NUCKS II)，细胞生长的刺激因子，热休克蛋白27，细胞存活的刺激因子，以及核小体组装蛋白-1(NAP-L)，细胞增殖的刺激因子。通过消减杂交，我们意外地发现，在可逆性缺血/再灌注和慢性左心室肥厚的大型哺乳动物模型中，H11激酶转录本和蛋白表达上调。我们的初步数据显示，在分离的心肌细胞中过表达H11激酶可以促进细胞生长。已经建立了心脏特异的转基因小鼠，证实了H11激酶的过表达在体内诱导了心肌肥大，并保护了细胞在缺血/再灌注期间的死亡。基于这些观察，这项建议的总体目标是确定H11激酶在心肌中的生理作用、信号机制和功能重要性。第一个特定的目的是在体内确定心脏特异的转基因小鼠模型中H11激酶的过度表达对功能和基因组的影响。我们假设，在转基因小鼠中过表达H11激酶将减少肥大和缺血心脏的不可逆细胞损伤。第二个目的是确定整合H11激酶的信号通路。我们推测，H11激酶通过刺激NUCKS II、HSP27和NAP-L促进心脏生长和存活，但其他意想不到的蛋白也可能相互作用。第三个目的是在体外和体内通过基因敲除模型证明H11激酶代表心脏生长和存活的一条基本途径。我们推测，H11激酶的组织限制性表达是一条特定的信号通路的基础，对于正常的心肌细胞生长来说，这条通路是必不可少的。这些实验将揭开心脏生长的新机制和信号通路，这可能会为缺血性心脏病和心力衰竭开辟新的治疗途径。