干旱胁迫下玉米开花期雄穗差异表达蛋白质的鉴定与筛选

【目的】 研究玉米开花期不同耐旱性玉米自交系的蛋白质表达差异,分析玉米响应干旱胁迫的主要代谢途径并发掘有价值的耐旱基因,对响应干旱胁迫的差异表达蛋白质组进行筛选和鉴定分析。【方法】 以强耐旱系PHBA6和弱耐旱系吉63为材料,设计干旱胁迫和正常灌溉处理。在玉米开花期进行干旱胁迫处理,取雄穗小花提取蛋白经双向凝胶电泳分离、凝胶图像扫描和质谱分析。【结果】 质谱分析共筛选出542个高清晰、重复性强的蛋白质点。其中,差异表达丰度达2.0倍以上的蛋白质点共有59个,强耐旱系PHBA6中有26个,弱耐旱系吉63中有37个,在强耐旱系PHBA6与弱耐系吉63中都表达且差异显著的蛋白质点有4个。【结论】 干旱胁迫蛋白参与代谢物和能量前体合成、核苷酸代谢、氧化还原辅酶代谢过程、蛋白翻译调控、细胞蛋白质及氨基酸代谢过程的调控、含硫化合物的合成与代谢过程、半胱氨酸的生物合成及代谢过程和光合作用等。细胞组分分类显示二者中的差异蛋白都与叶绿体及其结构相关,而且差异蛋白的细胞组分分类一致,但在生物学代谢过程及分子功能分类上相差较大,这些显著的差异表达的蛋白可能是形成不同品系间耐旱性强弱的主要原因。

Identification and Screening of Differentially Expressed Proteins in Maize TasseLAt Anthesis under Drought Stress

【Objective】 In this project, PHBA6 with strong drought tolerance and J63 with weak drought tolerance were used as testing materials to design drought stress and normal irrigation treatment. The difference of protein expression in maize inbred lines with different drought tolerance during flowering period was further studied, the main metabolic pathways of maize in response to drought stress were mastered, and valuable drought tolerance genes were discovered, and the differential expression proteome in response to drought stress was screened and identified.【Methods】 During the flowering period of maize, the protein was extracted from male tassel florets under drought stress, and the protein was separated by two-dimensional gel electrophoresis, gel image scanning and mass spectrometry.【Results】 A total of 542 protein spots with high resolution and strong repeatability were screened by mass spectrometry. Among them, there were 59 protein sites with the differential expression abundance of more than 2.0 times, 26 in the strong drought-tolerant line PHBA6, 37 in the weak drought-tolerant line J63, and 4 in the strong drought-tolerant line PHBA6 and the weak drought-tolerant line J63.【Conclusion】 Drought stress proteins were involved in the synthesis of metabolites and energy precursors, nucleotide metabolism, REDOX coenzyme metabolism, protein translation regulation, regulation of celLProtein and amino acid metabolism, synthesis and metabolism of sulfur containing compounds, biosynthesis and metabolism of cysteine, and photosynthesis. The classification of cell components showed that the differentially expressed proteins were related to chloroplasts and their structures, and the cell components of differentially expressed proteins were consistent, but the differences in biological metabolic processes and molecular functions were significantly different. These significantly differentially expressed proteins may be the main reason for the formation of drought tolerance between different strains.