西藏青稞品系藏青13氮胁迫的蛋白组学分析

Analysis of Proteomics of Tibetan Hulless Barley Zangqing 13 in Response to Endure Nutrient Deficiency

氮元素过多过少都可能导致植株表型发生明显变化,甚至影响植株的正常生长发育。为了探究西藏青稞对不同氮浓度的响应,本研究采用藏青13作为材料,利用同位素相对标记与绝对定量技术(isobaric tags for relative and absolute quantitation, Itraq)标记联合液相色谱串联质谱(LC-MS/MS)技术并结合生物信息学和分子生物学技术对适氮、缺氮、低氮和高氮处理样品的蛋白谱进行分析。iTRAQ测序结果表明,在根组织共鉴定得到8589个蛋白质,肽链长度主要分布在6～18个氨基酸之间;在叶组织中鉴定得到4608个蛋白质,肽链长度主要分布在6～16个氨基酸之间。COG分析显示,R类蛋白数量最多,同时鉴定的蛋白涉及次生代谢生物合成、信号转导、防御机制等多个方面。在不同氮素浓度处理下,其中缺氮处理与对照(适氮处理)相比,所筛选到的差异蛋白最多,有1518个蛋白,其中810个上调,708个下调。四个处理共同筛选到的差异蛋白共富集到47个功能项中,包含20个生物过程GO功能项,15个细胞组分GO功能项,12个分子功能GO功能项。

Excessive and too little nitrogen can cause significant changes in plant phenotype, and even lead to plant growth and development. In order to deep our understanding of the response mechanism of hulless barley to respond to different nitrogen stress, we used Zangqing 13 as experimental material to analyze the different protein profile of hulless barley induced by different nitrogen stress （ optimal-nitrate （ON） treatment,low-nitrate （LN） treatment,free-nitrate （FN） treatment, hight-nitrate （HN） treatment） using iTRAQ labeling techniques corn- bined with bioinformatics and molecular biology assays. The results showed that 8589 proteins were identified in the root tissue by iTRAQ se- quencing analysis. The peptide chain length was mainly distributed between 6 and 18 amino acids; there were 4608 proteins Mentified in the leaf tissue. The peptide chain length was mainly distributed in the between 6 and 16 amino acids. COG analysis showed that the number of R-class proteins was the highest, and the identified proteins involved in secondary metabolic biosynthesis, signal transduction, and defense mechanisms. Under different nitrate concentrations, the difference between the free-nitrate treatment and optimal-nitrate treatment was the highest, with 1518 proteins, of which 810 were up-regulated and 708 were down-regulated. The tour differentially screened proteins were en- riched into 47 functional items, including 20 GO functional categories in the biological process, 15 GO functional categories in the cellular components, and 12 GO functional categories in the molecular function.