桑突变体Cty-Ym叶片蛋白质的双向电泳及质谱分析

Analysis of Leaf Proteins From Mulberry Mutant Cty-Ym by Using Mass Spectrometry and Two-dimensional Electrophoresis

为探讨桑树叶色突变体CtyYm变异的分子机理,采用蛋白质组学分析技术,从突变体和对照桑中提取并分离叶片蛋白质,获得了IEF/SDSPAGE双向电泳图谱,在CBB染色条件下,检测到比较清晰的蛋白质点184个;经PDQuest软件分析,发现两者蛋白质点的相对含量有36处存在显著差异(±2倍),尤其是突变体中蛋白质点SSP2801的相对含量仅为对照桑的258%,经胶内酶切、LCESIQTOFMS分析、肽质量和碎片离子检索分析,鉴定该蛋白组分为RuBisCO大亚基,推测突变体CtyYm叶色黄化可能与RuBisCO大亚基含量减少有关。

To probe the molecular mechanism of leaf etiolation in mulberry mutant,we separated the total leaf proteins from mutant and wild type of mulberry with isoelectric focusing-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (IEF/SDS-PAGE).After staining with CBB,184 protein spots were detected.Analysis with PDQuest software showed that protein content of 36 spots differs remarkably in wild type and mutant (±2-fold),especially the amount of protein on the spot SSP 2801 in mulberry mutant was only as much as 25.8% of that in control.The protein on spot SSP 2801 was subjected to In-gel digestion followed by LC-ESI-Q-TOF MS analysis.The result of MS fingerprinting confirmed that the protein is the large subunit of RuBisCo,suggesting that the amount of the large subunit of RuBisCo is related to the leaf etiolation in mutant Cty-Ym.