Photoinhibition and D1 protein degradation in mesophyll and agranal bundle sheath thylakoids of maize.
Photoinhibition and D1 protein degradation in mesophyll and agranal bundle sheath thylakoids of maize.
复制标题
玉米叶肉和无头束鞘类囊体的光抑制和 D1 蛋白降解。
DOI：
10.1071/fp07067
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
E. Romanowska
中科院分区：
文献类型：
--
作者：
B. Pokorska;E. Romanowska
光系统 II 复合体 (PSII) 对光抑制和 D1 蛋白降解的敏感性已在 C3 植物的叶绿体中得到描述，但迄今为止，PSII 周转尚未在任何 C4 植物中得到表征，C4 植物含有两种在生化和结构上不同的叶绿体。在玉米 (Zea mays L. Oleńka) 中，叶肉 (M) 中的叶绿体发育基粒，而束鞘 (BS) 叶绿体则发育为无粒基粒。在本文中，我们报道了玉米植物叶肉以及无头束鞘类囊体中 D1 蛋白的磷酸化、损伤和蛋白水解。对分离的类囊体进行光抑制处理（1800μmol光子m-2s-1）导致PSII电子传递的供体侧抑制，然后导致M和BS类囊体的反应中心受损。 BS 中的 D1 降解速率比 M 类囊体中的更快，并且向培养介质中添加 ATP 延迟了两种类型类囊体中的 D1 降解。此外，我们证明属于 FtsH 和 Deg 家族的蛋白酶存在，但它们的量在 M 和 BS 类囊体中显着不同。蛋白酶抑制剂研究表明丝氨酸和金属蛋白酶参与 D1 蛋白的降解。 BS 类囊体中 D1 降解循环的明显存在以及负责该过程的蛋白水解酶的存在证实了 PSII 在无头膜中发挥着重要作用，当受损时，D1 可以快速降解，从而使这些膜中的 PSII 修复和恢复。
Susceptibility of photosystem II complex (PSII) to photoinhibition and degradation of D1 protein has been described in the chloroplasts of C3 plants but so far, the PSII turnover has not been characterised in any C4 plant, which contains two types of chloroplasts differing biochemically and structurally. In maize (Zea mays L. Oleńka), chloroplasts located in mesophyll (M) develop grana, while bundle sheath (BS) chloroplasts are agranal. In this paper, we report the D1 protein phosphorylation, damage and proteolysis in mesophyll as well as in agranal bundle sheath thylakoids of maize plants. Photoinhibitory treatment (1800 μmol photons m-2 s-1) of isolated thylakoids led to donor side inhibition of PSII electron transport and then to damage of reaction centre in both M and BS thylakoids. Rate of D1 degradation rate was faster in BS than in M thylakoids, and the addition of ATP to incubation medium delayed D1 degradation in both types of thylakoids. Furthermore, we demonstrated that the proteases belonging to FtsH and Deg families were present but their amounts significantly differed in M and BS thylakoids. Protease inhibitor studies revealed that serine- and metallo-proteases were involved in degradation of D1 protein. Apparent existence of D1 degradation cycle and the presence of proteolytic enzymes responsible for this process in BS thylakoids confirm that PSII plays an important role in agranal membranes, and when damaged, D1 can be rapidly degraded to enable PSII repair and restoration in these membranes.
温带森林常绿阔叶树种冬季寒冷诱导的光抑制作用导致 RuBP 羧化和再生能力下降
DOI：
--
发表时间：
2007
期刊：
Functional Plant Biology 34(5)
影响因子：
--
作者：
Miyazawa Y.;Kikuzawa K. and Otsuki K.
通讯作者：
Kikuzawa K. and Otsuki K.
影响因子：
2.9
作者：
Ohnishi, N;Allakhverdiev, SI;Murata, N
通讯作者：
Murata, N