在uvomorulin的一个Ca2+结合部位中单个氨基酸的替代取消了粘合功能
1Max-Planck Institut für Immunobiologie, Molekulare Embryologie, Freiburg, Federal Republic of Germany.
Cell
|November 30, 1990
概括
一种合成和突变型乌沃莫鲁林表明, (Ca2+) 结合对于细胞粘附至关重要. 取代单个酸会破坏这种结合,取消该分子的粘合功能.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 乌沃莫鲁林是一种细胞粘附分子,对组织完整性至关重要.
- 已知离子 (Ca2+) 对于uvomorulin的功能至关重要.
- 单个Ca2+结合点在uvomorulin的粘合功能中的确切作用尚未完全阐明.
研究的目的:
- 研究一种特定的Ca2+结合基因在uvomorulin的功能中的作用.
- 为了确定这种基因中的氨基酸替代对Ca2+结合和细胞粘附的影响.
主要方法:
- 一个模仿uvomorulin Ca2+结合部位的的合成.
- 网站导向的uvomorulin的突变发生以改变关键氨基酸 (Asp到Lys或Ala).
- 在L细胞中突变uvomorulin的表达.
- 卡二+/素消化试验.
- 细胞聚合测试. 细胞聚合测试.
主要成果:
- 一种对应于uvomorulin Ca2+结合基因的合成可以成功地复合Ca2+.
- 在中用 Lys 取代 Asp 消除了 Ca2+ 复合.
- 突变的乌莫鲁林蛋白与Asp到Lys或Ala的替代物显示出对Ca2+/trypsin消化变化的敏感性.
- 这两种突变的乌莫鲁林蛋白都未能在聚合试验中调节细胞粘附性.
结论:
- 在特定的Ca2+结合部位内的单个酸残留物对于uvomorulin的粘合功能至关重要.
- 这种Ca2+结合部位的破坏导致细胞粘附的完全丧失.
- 这些发现强调了特定的Ca2+相互作用对细胞粘附的分子机制的关键重要性.
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