Stimulation of chlororespiration by heat and high light intensity in oat plants.
Stimulation of chlororespiration by heat and high light intensity in oat plants.
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DOI：
10.1111/j.1365-3040.2006.01510.x
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发表时间：
2006-08
期刊：
影响因子：
--
通讯作者：
M. J. Quiles
中科院分区：
文献类型：
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作者：
M. J. Quiles
高光照和中等热量抑制燕麦光合机构的活性。叶子高光强结合高温下孵育的燕麦叶片强烈降低了光系统（PS）II的最大量子产率，这表明PS II抑制和随后的不可逆损害光合机构的胁迫因素的密切协同作用。PS I A/B蛋白水平在高光强或中等热量下培养的叶片中保持与对照值相似，并且仅在两种胁迫因子同时施加时才下降。免疫印迹分析的类囊体膜使用的特异性抗体提出的NDH-K亚基的类囊体的NADH脱氢酶复合物（NADH DH）和对质体末端氧化酶（PTOX），揭示了增加的量的两种蛋白质在响应高的光强度和/或热处理。此外，这些应激处理还刺激了NADPH和铁氧还蛋白向质体醌提供电子的活性、质体醌氧化中的PTox活性以及类囊体膜中的NADH DH活性。与PTOX抑制剂没食子酸正丙酯孵育抑制了强光和高温下NDH-K和PTOX水平的升高，并轻微刺激了NADPH和铁氧还蛋白向质体醌的电子供体活性。抗霉素A（一种循环电子流抑制剂）提高了在强光和高温下培养的叶片类囊体膜中的NADH DH活性，并保持了NDH-K和PTOX的水平。PTOX和类囊体NADH DH复合物在这些胁迫条件下的上调支持了氯呼吸在保护植物免受高辐射和中等热量的作用。
High irradiance and moderate heat inhibit the activity of the photosynthetic apparatus of oat (Avena sativa L.) leaves. The incubation of oat leaves under high light intensity in conjunction with high temperatures strongly decreased the maximal quantum yield of photosystem (PS) II, indicating the close synergistic effect of both stress factors on PS II inhibition and the subsequent irreversible damage to the photosynthetic apparatus. The PS I A/B protein levels remained similar to control values in leaves incubated under high light intensity or moderate heat, and decreased only when both stress factors were simultaneously applied. Immunoblot analysis of thylakoid membranes using specific antibodies raised against the NDH-K subunit of the thylakoidal NADH dehydrogenase complex (NADH DH) and against plastid terminal oxidase (PTOX) revealed an increase in the amount of both proteins in response to high light intensity and/or heat treatments. In addition, these stress treatments were seen to stimulate the activity of electron donation by NADPH and ferredoxin to plastoquinone, the PTOX activity in plastoquinone oxidation and the NADH DH activity in thylakoid membranes. Incubation with n-propyl gallate (an inhibitor of PTOX) inhibited the increase of NDH-K and PTOX levels under high light intensity and heat, and slightly stimulated the activity of electron donation by NADPH and ferredoxin to plastoquinone. Antimycin A (an inhibitor of cyclic electron flow) increased the NADH DH activity and preserved the levels of NDH-K and PTOX in thylakoid membranes from leaves incubated under high light intensity and heat. The up-regulation of the PTOX and the thylakoidal NADH DH complex under these stress conditions supports a role for chlororespiration in the protection against high irradiance and moderate heat.