Han Feng, Chen Hui, Li Xiao-Juan, Yang Ming-Feng, Liu Gong-She, Shen Shi-Hua
Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, P.R. China.
Biochim Biophys Acta. 2009 Nov;1794(11):1625-34. doi: 10.1016/j.bbapap.2009.07.013. Epub 2009 Jul 25.
To understand the responses of rice seedlings to different high-temperature stresses, seven-day-old rice seedlings were exposed to different high temperatures for 48 h, and the maximal quantum yield of PS II photochemistry measurements, ascorbate peroxidase activity assays and proteomic analyses in leaf tissue were performed. The results showed that when rice seedlings were exposed to high temperatures at 35 degrees C, 40 degrees C and 45 degrees C, the maximal quantum yield of photosystem II photochemistry, the activity of ascorbate peroxidase and the proteome changed greater at higher temperature. The proteomics analysis showed that proteins such as lignification-related proteins were regulated by high temperature and distinct proteins related to protection were up-regulated at different high temperatures. All the results indicated that different strategies were adopted at different levels of high temperature: the higher the temperature, the more protection machineries were involved. At 35 degrees C, some protective mechanisms were activated to maintain the photosynthetic capability. At 40 degrees C, antioxidative pathways were also active. When rice seedlings encountered high-temperature stress at 45 degrees C, in addition to those induced at 35 degrees C and 40 degrees C, heat shock proteins were effectively induced.
为了解水稻幼苗对不同高温胁迫的响应，将7日龄水稻幼苗置于不同高温下处理48小时，并对叶片组织进行PS II光化学最大量子产率测定、抗坏血酸过氧化物酶活性测定和蛋白质组学分析。结果表明，当水稻幼苗暴露于35℃、40℃和45℃的高温下时，光系统II光化学的最大量子产率、抗坏血酸过氧化物酶的活性以及蛋白质组在较高温度下变化更大。蛋白质组学分析表明，木质化相关蛋白等蛋白质受高温调控，不同高温下与保护相关的不同蛋白质上调。所有结果表明，在不同高温水平下采取了不同的策略：温度越高，参与的保护机制越多。在35℃时，一些保护机制被激活以维持光合能力。在40℃时，抗氧化途径也很活跃。当水稻幼苗在45℃遭遇高温胁迫时，除了在35℃和40℃诱导的那些机制外，热休克蛋白也被有效诱导。
