克拉米多莫纳斯核NAC2位点的突变特别影响了质体psbD转录编码PS II的多D2的稳定性
M R Kuchka1, M Goldschmidt-Clermont, J van Dillewijn
1Department of Plant, University of Geneva, Switzerland.
Cell
|September 8, 1989
概括
NAC2基因产物稳定了克洛洛普拉斯特D2蛋白 (psbD) 转录在克拉米多蒙亚 reinhardtii. 如果没有NAC2,psbDmRNA会降解,导致不稳定的光系统II (PSII) 综合体.
科学领域:
- 分子生物学分子生物学
- 光合作用研究研究 光合作用研究
- 植物遗传学 植物遗传学
背景情况:
- 叶绿体D2蛋白对光系统II (PSII) 功能至关重要.
- 转录稳定性对于适当的蛋白质合成和复杂组合至关重要.
- 核编码的因素可以调节克洛洛普拉斯特基因表达在克拉米多蒙纳斯 reinhardtii.
研究的目的:
- 研究NAC2基因在调节质细胞基因表达中的功能.
- 确定NAC2在编码D2蛋白的psbD转录的稳定性中的作用.
- 了解NAC2对光系II复合体组合和稳定性的影响.
主要方法:
- 在野生型和nac2突变菌株中分析psbD转录水平.
- 在nac2突变体中评估PS II蛋白积累和复合体稳定性.
- 研究影响psaA拼接和NAC2功能的双变异体中的拼接中间体.
主要成果:
- 纳克2-26突变阻止了psbD转录的积累.
- PS II 复合体是不稳定的,主要的 PS II 聚在 nac2-26 突变体中被降解.
- 含有psbD序列的拼接中间体在缺少NAC2和psaA拼接的双突变体中降解.
- NAC2基因产物特别控制了psbD转录的半衰期.
结论:
- NAC2基因编码了一种对psbDmRNA稳定性至关重要的核因子.
- 通过NAC2介导的psbD转录稳定性对于光系统II复合体完整性至关重要.
- NAC2的功能特定于psbD转录处理,并且不会广泛影响其他PS II组件或psaA拼接.
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