增强UVB辐射对菜豆蛋白质代谢的影响

Effects of Enhanced UV B Radiation on Protein Metabolism of Bean Leaves 

模拟研究了温室条件下兰州地区臭氧层减薄２５ ％ 时增强的ＵＶＢ（２８０ ～３２０ ｎｍ） 辐射对菜豆（ Ｐｈａｓｅｏｌｕｓｖｕｌｇａｒｉｓ Ｌ．） 蛋白质代谢的影响。菜豆幼苗期，ＵＶＢ辐射（ＵＶＢＢＥ：１６ ｋＪ·ｍ －２·ｄ－１） 促进菜豆叶片中蛋白质的合成；菜豆生长后期，ＵＶＢ辐射则抑制蛋白质的合成，降低叶片中可溶性蛋白质的含量，促进蛋白水解酶活性的上升和总游离氨基酸的积累。ＳＤＳＰＡＧＥ分析表明，ＵＶＢ辐射使幼苗期菜豆叶片中８８ ｋＤ、７６ ｋＤ、４２ ｋＤ、３５ ｋＤ、３３ ｋＤ 多肽的含量上升；而在菜豆生长后期，ＵＶＢ辐射使大分子量多肽（７６ ｋＤ 以上） 的含量迅速下降，１０～１４ ｋＤ、２９ ｋＤ、３３ ｋＤ、３５ｋＤ的多肽含量上升。

Bean ( Phaseolus vulgaris L.) seedlings were grown in a greenhouse condition under UV B (280～320 nm) radiation and an UV B free control condition. At early stage of bean growth, UV B radiation(UV B BE :16 kJ·m 2·d -1 ) increased the synthetic rate of protein in bean leaves. UV B radiation decreased the synthetic rate of protein and the content of soluble protein, increased the activities of caseolytic enzymes and the content of total amino acids in bean leaves at later growth stage. The results of SDS PAGE indicated that UV B radiation increased the contents of polypeptide in a range of 99 kD,88 kD,76 kD,42 kD,35 kD and 33 kD at the early stage, and increased that of 10～14 kD,29 kD,33 kD and 35 kD at later growth stage. It is suggested that the increase of these polypeptides is an adaptation response of plants to the enhanced UV B radiation.