NUCLEAR MUTATION LEADS TO AN ACCELERATED TURNOVER OF CHLOROPLAST-ENCODED 48 KD AND 34.5 KD POLYPEPTIDES IN THYLAKOIDS LACKING PHOTOSYSTEM-II
NUCLEAR MUTATION LEADS TO AN ACCELERATED TURNOVER OF CHLOROPLAST-ENCODED 48 KD AND 34.5 KD POLYPEPTIDES IN THYLAKOIDS LACKING PHOTOSYSTEM-II
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DOI：
10.1002/j.1460-2075.1985.tb03832.x
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发表时间：
1985-01-01
期刊：
影响因子：
11.4
通讯作者：
MCINTOSH, L
中科院分区：
文献类型：
--
作者：
LETO, KJ;BELL, E;MCINTOSH, L
研究了无法组装光系统 II 反应中心的核玉米突变体中叶绿体编码的 48 kd（千道尔顿）chla 反应中心蛋白和 34.5 kd 阿特拉津结合蛋白的合成和积累。这些多肽未能在突变类囊体中积累并不是由于核对其合成的直接控制，而是由于它们在类囊体膜上的特定的、加速的周转。突变类囊体中这些多肽的加速周转很大程度上与光照条件无关，因为加速周转发生在黑暗和光照下。与野生型相反，48kd和34.5kd多肽优先与突变体膜中的基质而不是基粒、片层相关，这表明在这些多肽在基粒中富集之前发生转换。因此，细胞核在这些叶绿体编码的光系统II反应中心多肽的稳定中发挥作用。
The synthesis and accumulation of a chloroplast-encoded 48 kd (kilodalton) chla-reaction center protein and the 34.5 kd atrazine binding protein in a nuclear maize mutant which fails to assemble photosystem II reaction centers was studied. The failure of these polypeptides to accumulation in mutant thylakoids is not due to direct nuclear control over their synthesis but is rather due to their specific, accelerated turnover from the thylakoid membrane. The accelerated turnover of these polypeptides in mutant thylakoids is largely independent of illumination conditions, as accelerated turnover occurs in the dark and in the light. In contrast to wild type, the 48 kd and 34.5 kd polypeptides are preferentially associated with stroma, rather than grana, lamellae in mutant membranes, suggesting that turnover occurs before these polypeptides become enriched in the grana. The nucleus thus plays a role in the stabilization of these chloroplast-encoded photosystem II reaction center polypeptides.