MYOSIN I BETA DISRUPTION & INNER EAR STRUCTURE/FUNCTION

肌球蛋白 I Beta 破坏

• 批准号: 6497127
• 负责人: JOHN A MERCER
• 金额: $ 34.32万
• 依托单位: MC LAUGHLIN RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6497127
• 关键词: Baculoviridae; ear hair cell; enzyme activity; enzyme inhibitors; gene mutation; genetically modified animals; isozymes; laboratory mouse; myosins; newborn animals; nucleic acid sequence; transfection /expression vector

DESCRIPTION (adapted from applicant's abstract): The overall goal of this collaborative project is to determine whether myosin 1b is the adaptation motor, to ascertain the role of myosin 1b in other hair cell functions, and to dissect the hair cell roles of myosins VI, VIIa, and XV. In their approach, the investigators developed a mutant/inhibitor strategy that allows them to test the role of a myosin isozyme in a given cellular function. By mutating myosin in a manner that maintains normal ATP hydrolytic and chemomechanical activity, yet greatly enhances binding of an inhibitor, they sensitize myosin to the inhibitor. They then show that the inhibitor has an effect on the hair cell function of interest only when the sensitized myosin transgene is expressed in hair cells. During the initial funding period, they designed such a mutation in myosin 1b, Y61G, which sensitizes the mutant protein to N6-modified ADP analogs. In this renewal application, they propose to complete their examination of the role of myosin 1b in slow adaptation, examining the effects of the ADP analogs in hair cells that express Y61G myosin 1b using transgenic or knock-in methods. They will also determine whether myosin 1b sets hair cell resting tension and examine whether it participates in restoration of functional transduction after the hair cell's tip links are broken. The latter two goals will require development of new myosin inhibitors that can freely pass across cell membranes. Finally, they propose to use the knowledge of effective mutant/inhibitor combinations developed for myosin 1b to examine roles for three myosin isozymes that are essential for hair cell function, myosins VI, VIIa, and XV. After developing myosin mutants and selective inhibitors, they will use assays for transduction and adaptation, bundle development, apical endocytosis, and aminoglycoside uptake to determine where and when these myosin isozymes are required in hair cells.

描述（改编自申请人的摘要）：此的总体目标 协作项目是确定肌球蛋白1b是否是适应 电机，确定肌球蛋白1b在其他毛细胞功能中的作用，并 剖析肌球蛋白VI，VIIA和XV的毛细胞角色。在他们的方法中 研究人员制定了一种突变/抑制剂策略，使他们能够测试 肌球蛋白同工酶在给定的细胞功能中的作用。通过突变肌球蛋白 以维持正常ATP水解和化学力学活性的方式 然而，它们大大增强了抑制剂的结合，它们使肌球蛋白敏感 抑制剂。然后他们表明抑制剂对毛细胞有影响 仅当在敏化的肌球蛋白转基因表达时，感兴趣的功能 毛细胞。在最初的资金期间，他们在 肌球蛋白1b，Y61G，将突变蛋白敏感到N6修饰的ADP 类似物。在此续签应用中，他们建议完成他们的 检查肌球蛋白1b在缓慢适应中的作用，检查效果 使用转基因表达Y61g肌球蛋白1b的毛细胞中的ADP类似物 或敲门方法。他们还将确定肌球蛋白1b是否设置了毛细胞 安息紧张并检查它是否参与 毛细胞的尖端链路后的功能转导断裂。后者 两个目标将需要开发可以自由的新肌球蛋白抑制剂 通过细胞膜。最后，他们建议利用 为肌球蛋白1B开发的有效突变/抑制剂组合检查 三个对于毛细胞功能必不可少的肌球蛋白同工酶的角色， 肌球蛋白VI，VIIA和XV。在发展肌球蛋白突变体和选择性之后 抑制剂，他们将使用测定法进行转导和适应，束 发育，顶端内吞作用和氨基糖苷的摄取，以确定 当毛细胞中需要这些肌球蛋白同工酶时。