He-Ne激光和增强UV-B辐射对小麦幼叶叶绿素荧光和Rubisco活化酶的影响

Effects of He-Ne Laser and UV-B Radiation on Chlorophyll Fluorescence and Rubisco Activase of Wheat Leaves

选用小麦‘ML7113’品种为材料,人工模拟He-Ne激光(5mJ·s-1·mm-2)、增强UV-B(10.8kJ·m-2·d-1)辐射及两者复合辐照进行处理,利用叶绿素荧光仪、考马斯亮蓝G-250染色法和PCR技术研究7d龄小麦幼苗叶绿素荧光特性、Rubisco活化酶含量、基因表达量及其基因序列的变化。结果表明:(1)与对照组相比,增强UV-B辐射后,小麦幼苗叶绿素荧光特性减弱,Rubisco活化酶含量及其基因表达量均下降;而低剂量的He-Ne激光辐照后能够在一定程度上修复经UV-B辐射后对小麦幼苗叶绿素荧光特性所造成的损伤,且使Rubisco活化酶含量及其基因表达量上升。(2)与对照组相比,经He-Ne激光和增强UV-B辐射以及两者复合辐照处理后基因序列均出现两个相同的点突变,但并未造成氨基酸序列的变化。研究认为,低剂量He-Ne激光辐照能够在一定程度上修复受UV-B辐射小麦幼苗叶绿素荧光活性、Rubisco活化酶含量及其基因表达量的降低;He-Ne激光和增强UV-B辐射对小麦幼苗Rubisco活化酶活性的影响可能发生在其转录水平,从而使小麦光合能力发生相应的变化。

With ‘ML7113＇ wheat seedlings as the materials,artificial simulation of He-Ne laser（5 mJ·s-1 ·mm-2）,enhanced UV-B（10.8 kJ·m-2·d-1）radiation and combined radiation processing.Using chlorophyll fluorescence spectrometer,coomassie brilliant blue G-250 dyeing method and PCR technique,we studied the changes of chlorophyll fluorescence characteristics,content of rubisco activase,changes of gene expression and gene sequence on seven day age of wheat seedling.The results show that：（1）Compared with the control group,after enhanced UV-B radiation,wheat seedling chlorophyll fluorescence characteristics is abate.Rubisco activase content and its gene expression quantity decreased.But low doses of He-Ne laser irradiation can repair the damage on wheat seedling chlorophyll fluorescence characteristics which caused by after UV-B radiation and make rubisco activase content and its gene expression increased.（2） Compared with the control group,after He-Ne laser and enhanced UV-B radiation and combined irradiation gene sequences were presented with two identical point mutations,but did not cause the change of amino acid sequence.Visible,low dose He-Ne laser irradiation can be repaired by UV-B radiation on chlorophyll fluorescence activity of wheat seedlings to a certain extent and make the rubisco activase content and its lower amount of gene expression.Speculate that the influence of He-Ne laser and enhanced UV-B radiation on wheat seedling rubisco activase due to the change of transcriptional.So that the wheat photosynthetic capacity was changed accordingly.