Formation of oxygen-evolving system of photosynthesis

光合作用释氧系统的形成

• 批准号: 02640523
• 负责人: YAMAMOTO Yasusi
• 金额: $ 1.09万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02640523/
• 关键词: photosynthesis; oxygen evolution; chloroplast; photosystem II; protein; protein transport; photoinhibition; 酵素発生; 緑化; 遺伝子発現; 蛋白質輸送; クロロフィルタンパク質; 翻訳後調節

Photosynthetic oxygen-evolving system is organized by the coordinated assembly of the nuclear- and chloroplast-encoded proteins in thylakoid membranes under illumination. In the present study, we investigated synthesis and assembly of the PS-II related proteins in the greening process of Euglena cells and barley seedlings. In Euglena, the antenna chlorophyll-binding proteins CP43/47 are unstable in the early stage of greening, and we found that binding of extrinsic 30 kDa proteins to PS II is responsible for the stabilization of CP43/47. The results suggest that the extrinsic 30 kDa proteins are located closely to the antenna chlorophyll-protein complexes and regulates their conformation.We also studied transport of the 30 kDa protein in Euglena cells. To see the structure of the precursor to the 30 kDa protein, we carried out cDNA cloning of the protein. The precursor had a presequence different from that of the corresponding protein from higher plants. Contact sites of the envelope of chloroplasts, which are responsible for translocation of the precursor proteins across the envelopes, were examined by electron microscopy. It is probable that transport of nuclear-encoded proteins in chloroplasts is limited by the envelopes consisting of triple membranes.

光合放氧系统是通过在光照下类囊体膜中核和叶绿体编码蛋白质的协调组装来组织的。在本研究中，我们研究了眼虫细胞和大麦幼苗绿化过程中PS-II相关蛋白的合成和组装。在眼虫中，触角叶绿素结合蛋白 CP43/47 在变绿的早期阶段不稳定，我们发现外在 30 kDa 蛋白与 PS II 的结合负责 CP43/47 的稳定。结果表明，外源性30 kDa蛋白与触角叶绿素-蛋白复合物紧密相连，并调节其构象。我们还研究了眼虫细胞中30 kDa蛋白的转运。为了了解 30 kDa 蛋白质前体的结构，我们对该蛋白质进行了 cDNA 克隆。该前体具有与来自高等植物的相应蛋白质不同的前序列。通过电子显微镜检查叶绿体包膜的接触位点，这些位点负责前体蛋白穿过包膜的易位。叶绿体中核编码蛋白质的运输可能受到由三层膜组成的包膜的限制。

项目成果

I.KURODA: "Precursor for the nuclear-encoded extrinsic 30-kDa protein of Photosystem II in Euglena gracilis Z is not a polyprotein." Plant Mol.Biol.21. 171-176 (1993)

I.KURODA：“眼虫 Z 中光系统 II 的核编码外在 30-kDa 蛋白质的前体不是多蛋白。”

Yamamoto, Y.: "Characterization of early events leading to the formation of chlorophyll-proteins of PS II in Euglena gracilis Z." Physiol. Plantarum. 84. 403-408 (1992)

Yamamoto, Y.：“导致眼虫 Z 中 PS II 叶绿素蛋白形成的早期事件的特征。”

Hiramatsu, H.: "Relationship between the stability of antenna Chl a-binding proteins CP43/47 and the accumulation of the extrinsic 30-kDa protein in PS II in Euglena." Plant Cell Physiol. 32. 881-889 (1991)

Hiramatsu, H.：“眼虫天线叶绿素 a 结合蛋白 CP43/47 的稳定性与 PS II 中外在 30-kDa 蛋白的积累之间的关系。”

Kuroda, I.: "Precursor for the nuclear-encoded extrinsic 30-kDa protein of photosystem II in Englena gracilis Z is not a polyprotein." Plant Mol. Biol. 21. 171-176 (1993)

Kuroda, I.：“Englena gracilis Z 中光系统 II 的核编码外在 30-kDa 蛋白质的前体不是多蛋白。”

H.HIRAMATSU: "Relationship between the stability of antenna Chla-binding proteins CP43/47 and the accumulation of the extrinsic 30-kDa protein in PS II in Euglena." Plant Cell Physiol.32. 881-889 (1991)

H.HIRAMATSU：“眼虫天线 Chla 结合蛋白 CP43/47 的稳定性与 PS II 中外在 30-kDa 蛋白的积累之间的关系。”