低温胁迫期间水稻光合膜色素与蛋白水平的变化

对４℃和１１℃两种低温胁迫过程中水稻类囊体膜色素与蛋白组成的变化进行了比较研究。结果表明：４℃低温不仅使类囊体膜中的光合色素（叶绿素、类胡萝卜素）含量降低，而且还引起膜蛋白组成的深刻变化，表现在大部分原有膜蛋白组分的含量在低温下明显降低，同时在低温处理的第３天诱导出一条３２．５ＫＤ的新蛋白带。与４℃处理相比，１１℃低温处理只引起了光合色素含量的降低，而对类囊体膜蛋白组成的影响不大，另外发现，两种低

Changes in components of pigments and proteins in rice photosynthetic membrane during chilling stress

A comparative study on changes in components of pigments and proteins in rice thylakoid membranes during 4℃ and 11℃ chilling stress was conducted.The results showed that low temperature at 4℃ not only decreased the contents of photosynthetic pigments (chlorophylls and carotenoids) but caused a profound variation in contents of the proteins in thylakoid membranes:most membrane proteins decreased progressively as the stress developed,and a new protein with a molecular mass of about 32.5 kD appeared on the third day of stress.Compared with 4℃,stress at 11℃ only caused decrease in contents of photosynthetic pigments,but had little effect on components and levels of thylakoid proteins.It was also found that treatments at both temperatures caused evident variation in the chla/b ratio.The chla/b ratio decreased at first during the early period of chilling stress (4℃,1 d and 11℃,2 d) but increased thereafter,suggesting that the reaction centres of the photosynthetic apparatus in plants are probably more sensitive to low temperature than the antenna components