淹水胁迫条件下玉米苗期叶片蛋白质组学分析

Proteomic analysis of maize seedling leaves subjected to waterlogging stress

采用双向电泳技术(2-DE)研究玉米苗期受淹后叶片的蛋白质组学差异,以进一步阐明玉米对淹水胁迫的响应机制。玉米种植10 d后进行72 h淹水处理,提取叶片总蛋白质、采用2-DE,利用图像分析,获得12个差异蛋白点。经鉴定得到9种蛋白质,这些蛋白质分别参与光合作用、氨基酸代谢、防御与胁迫和碳水化合物代谢等多个代谢过程。其中,参与光合作用、蛋白质折叠和氨基酸代谢的蛋白质表达基本被负调,而参与淀粉生物合成的2个蛋白质均上调。这说明淹水胁迫抑制了玉米的光合作用,而玉米植株则可能通过提高淀粉生物合成增加有机物质储备,从而有利于植株恢复。玉米对淹水胁迫的适应是一个复杂的生物过程,涉及到多种蛋白质的相互作用,构成了一个复杂的调控网络。

Two-dimensional electrophoresis（ 2-DE） technology were used to analyze the proteomic change of maize（ Zea mays L.） seedling leaves under waterlogging and normal conditions. Ten-dayold plants were subjected to waterlogging stress,and leaves were collected 72 hours after treatment.Then total proteins were extracted from leaf samples,separated by 2-DE,and visualized by staining with Coomassie Brilliant Blue. A total of 12 protein spots were differentially expressed in maize leaves in response to waterlogging stress,and 9 were successfully identified using matrix-assisted laser desorption / ionization time of flight mass spectrometry（ MALDI-TOF-TOF MS） analysis. These proteins were involved in several cellular processes,including photosynthesis,amino acid metabolism,defense and stress and carbohydrate metabolism. And proteins associated with photosynthesis,protein folding and amino acid metabolism were down-regulated by waterlogging,while two proteins related to starch biosynthesis process were up-regulated. These results suggested that waterlogging-stress could hinder the photosynthesis,leading to the assimilation inhibited,and biomass accumulation slowed,at the same time,maize might enhance the starch biosynthesis process to increase the torlerance to waterlogging.The maize adaptation to waterlogging was regulated by a complex network,multiple proteins of different metabolic pathways might participate in this process.