高产杂交水稻两优培九衰老进程中剑叶差异蛋白质组学分析

Comparative flag leaf proteomic profiling of high-yielding hybrid rice Liangyoupeijiu during senescence

以杂交水稻两优培九孕穗期和乳熟期的剑叶为试验材料进行蛋白质组学分析。结果显示:2个时期存在78个差异蛋白质点,其中53个被成功鉴定,涉及7个功能类别,即:光合作用、能量代谢、蛋白质代谢、脂质代谢、碳水化合物及氨基酸代谢、信号转导和胁迫响应。细胞代谢网络表现出合成代谢下降,物质转运活跃的趋势,而乳熟期叶片线粒体氧化磷酸化受阻则表明分解代谢可能也有所下降。光合作用是差异蛋白质网络的核心,乳熟期剑叶光系统II放氧中心复合物(Oxygen-evolving complex,OEC)、烟酰胺腺嘌呤二核苷酸磷酸氧化还原酶(Nicotinamide adenine dinucleotide phosphate oxidoreductase)、ATP合酶(ATP synthase)的表达量都显著降低,同时伴随着类囊体膜脂合成相关的甘油-3-磷酸乙酰转移酶(GPAT3)的表达下调。碳同化阶段的核酮糖-1,5-二磷酸羧化酶/加氧酶(Ru Bis CO)及其前体、活化酶(RCA)的表达也受到抑制。推测Harpin蛋白质结合蛋白1(Harpin binding protein 1,HrBP1)表达量的减少与叶绿体内部抗氧化系统能效的降低有关,防御蛋白下降造成的细胞内氧化失衡是水稻生长发育后期叶片衰老的重要诱因。

In this study,the flag leaves of hybrid rice Liangyoupeijiu in booting stage and milk stage were used as materials for proteomic analysis.All 53 in 78 differently expressed proteins were identified,which were defined into seven functional categories,i.e.,photosynthesis,energy metabolism,protein metabolism,lipid metabolism,carbohydrate and amino acid metabolism,signal transduction and stress response.Metabolic network were characterized by descended anabolism and active transport events.The catabolism probably decreased when oxidative phosphorylation in mitochondria was inhibited at milk stage.Photosynthesis was in the core of protein interaction network,where oxygen evolving complex(OEC),nicotinamide adenine dinucleotide phosphate oxidordeuctase and ATP synthase were significantly reduced.Concomitantly,glycerol 3 phosphate acyltransferase(GPAT3)involving in thylakoid lipid synthesis was down-regulated.For carbon assimilation,expression of ribulose bisphosphate carboxylase oxygenase(RuBisCO),RuBisCO precursor and RuBisCO activase(RCA)were also retarded.Impaired antioxidant system caused by less harpin binding protein 1(HrBP1)led to disrupted redox poise,which could be an inducement of senescence of flag leaves.