在视觉循环调节中的棕化开关机制
Linlong Xue1, Deviprasad R Gollapalli, Pranab Maiti
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 45 Shattuck Street, Boston, MA 02115, USA.
Cell
|June 10, 2004
概括
视网膜色素表皮蛋白65 (RPE65) 有两种形式:与膜相关的 (mRPE65) 和可溶的 (sRPE65). 棕化控制器 RPE6565 控制器
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 视觉科学 视觉科学 视觉科学
背景情况:
- 视网膜色素表皮蛋白65 (RPE65) 对于合成11-cis-retinal,即罗多素染色体至关重要.
- 视觉循环依赖于视觉的视网体的适当处理.
- 了解RPE65的功能是解决与视网代谢相关的视力障碍的关键.
研究的目的:
- 阐明膜相关 (mRPE65) 和可溶性 (sRPE65) 形式的RPE65.65的不同作用.
- 调查RPE65棕化在控制视网结合中的作用.
- 定义莱西丁网酸转移酶 (LRAT) 在调节RPE65活性中的作用.
主要方法:
- 关于RPE65棕化状态的表征.
- 对不同形式的RPE65的联结特异性的分析.
- 在RPE65相互转换中研究LRAT的酶活性.
主要成果:
- 与膜相关的RPE65 (mRPE65) 是三倍棕化和伴奏的全转网乙烯.
- 可溶性RPE65 (sRPE65) 不是棕化,是维生素A的伴侣.
- 莱西丁网酸转移酶 (LRAT) 作为一个分子开关,将mRPE65转换为sRPE65并控制染色体合成.
- 棕化RPE65作为棕酸的捐赠者,表明一种新型的酸载体蛋白的作用.
结论:
- RPE65的棕化决定了其连接体结合的选择性,使其在视觉循环中的角色有所区别.
- LRAT作为棕基转移酶起作用,催化mRPE65和sRPE65之间的转化,从而调节染色体合成.
- 棕化蛋白质可以充当分子开关,mRPE65是视网类代谢的一个关键例子.
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