光照因素封Rubisco酶在蛋白核内外分布的影响  

Effect of light regimes on Rubisco concentrating in pyrenoids from Enteromorpha clathrata

作　　者：蔡春尔[1] 尹顺吉[1] 汪卿[1] 柳俊秀[1] 李春霞[1] 何培民[1] 

机构地区：[1]上海海洋大学水座舆生命学院,上海201306

出　　处：《Journal of Life Sciences》2009年第7期1-9,共9页生命科学（英文版）

基　　金：本研究受国家自然科学基金（项目编号：30371101）,教育部博士点基金,上海市教委重点建设学科（项目编号：S30701）资助,特此感谢!

摘　　要：制备了条浒苔Rubisco酶及其抗体，并应用于研究光照因素对Rubisco酶在蛋白核内外分布的影响。应用生化技术分离纯化了条浒苔Rubisco酶，并免疫注射入兔体制备了Rubisco抗体，经鉴定Rubisco大小亚基分子量分别约为50kD和16kD，全酶的分子量在500kD左右。应用金标免疫电镜分子定位技术封Rubisco酶集中蛋白核程度进行数值化分析。发现在光强变化长期影响实验中，当藻体转入较高光强时，Rubisco明显由叶绿体基质向蛋白核中聚集，从而更好地完成其光合作用功能。在完全黑暗处理和光合作用阻断剂DCMU处理短期影响中，并未观察到PR-ratio的明显降低，但PR-ratio在24小时中的波动被提前，这可能是由于正常生物节律的破坏和藻类对不良环境的反应机制造成。此外，结果显示条浒苔封光强的微小变化并不敏感。Rubisco from Enteromorpha clathrata was separated and purified to obtain antibody against Rubisco for researchment on effect of light regimes on Rubisco concentrating in pyrenoids from Enteromorpha clathrata. Rubisco purified from Enteromorpha clathrata using biochemical techniques was injected into rabbits for its antibody. The molecular weight of Rubisco was about 500 kD, with the large subunit 50 kD and the small subunit 16 kD approximately. Immunogold electron microscopic technique was applied to quantify the degree of Rubisco concentrating in pyrenoids. In the long-term effect of different light intensities experiments, the obvious redistribution of Rubisco from the stroma to the pyrenoids was examined after exposed to higher light intensity. This result suggested that Rubisco tended to concentrate in the pyrenoids to fulfill its functions, catalyzing the key step of photosynthesis. In the short-term application of darkness and 3-（3,4-dichlorophenyl）-1,1-dimethyl urea （DCMU）, PR-ratio did not decrease markedly as we regarded before, but an advance of PR-ratio fluctuation in 24 hours was observed. This might be caused by the disturbing of ordinary fluctuation pattern and the corresponding adaptive mechanism in the multicellular alga Enteromorpha clathrata towards adverse environment. The result suggested that Enteromorpha clathrata was insensitive to slight variations in growth irradiance.

关 键 词：光照 条浒苔 Rubisco酶 蛋白核 

分 类 号：Q248[生物学—细胞生物学]