SPECIFIC INTEGRIN ALPHA 4 CYTOPLASMIC TAIL FUNCTIONS

描述(改编自申请者摘要)：细胞质 整合素α4亚单位的结构域与其他α亚基明显不同 与局灶性黏附形成相关的链状细胞质结构域，以及 这可能是细胞迁移增加但细胞减少的原因 铺展、粘合增强、质膜硬度和PIP4、5 综合。首席调查员假设，独特的 阿尔法-4尾巴内的结构特征产生了它的专门的 与特定的生化协会协调的功能和 信号通路。此外，首席调查者假设 α-4尾巴的这些独特特征在体内对正常 淋巴细胞生理学和炎症。为了检验这一假设，他 将：1)在体内评估α-4尾部突变体对血细胞的影响；2)使用 一组突变体，以确定导致 迁移、粘附力增强、与已知细胞骨架共聚 整合素α-4尾部的蛋白质和其他特殊功能； 3)比较肌醇磷脂的合成和其他信号功能 野生型和突变型α-4在K562细胞、CHO细胞和原代细胞中的表达 来自RAG-2嵌合小鼠的淋巴细胞。最低限度的使用 具有最大功能效应的突变将使他能够将 结论：α-4特定的正负功能效应 与特定的共定位蛋白和特定的信号通路也 他将有一个独特的机会在体内进行决定性的 α-4尾巴在正常血液成熟和成熟过程中的评价 在发炎期间。小鼠原代淋巴细胞的可利用性 表达突变型和野生型α-4将允许扩展分析 阿尔法-4特定的信号通路。

DESCRIPTION (Adapted from the Applicant's Abstract): The cytoplasmic domain of the integrin alpha4 subunit differs markedly from other alpha chain cytoplasmic domains with respect to focal adhesion formation, and this may account for increased cell migration but decreased cell spreading, adhesion strengthening, plasma membrane stiffness, and PIP4,5 synthesis. The principal investigator hypothesizes that distinctive structural features within the alpha-4 tail produce its specialized functions in coordination with specific biochemical associations and signaling pathways. Furthermore the principal investigator hypothesizes these unique features of the alpha-4 tail are critical in vivo for normal lymphocyte physiology and inflammation. To test this hypothesis he will: 1) evaluate alpha-4 tail mutants on blood cells in vivo; 2) use a panel of mutants to determine the exact tail residues responsible for migration, adhesion strengthening, coclustering with known cytoskeletal proteins and other specialized functions of the integrin alpha-4 tail; and 3) compare phosphoinositide synthesis and other signaling functions of wild type and mutant alpha-4 in K562 cells, CHO cells, and primary lymphocytes derived from RAG-2 chimeric mice. The use of minimal mutations with maximal functional effect will allow him to link conclusively alpha-4 specific positive and negative functional effects with specific colocalized proteins and specific signaling pathways Also he will have a unique opportunity to carry out definitive in vivo evaluations of the alpha-4 tail during normal blood maturation and during inflammation. The availability of primary mouse lymphocytes expressing mutant and wild type alpha-4 will allow an expanded analysis of alpha-4 specific signaling pathways.