基于iTRAQ的玉米V12时期响应干旱胁迫的蛋白质组学分析

Proteomic analysis of maize response to drought stress in the V12 stage based on iTRAQ technology

干旱是限制玉米生长和产量的主要非生物胁迫因素,且玉米的耐旱性是由多基因控制的数量性状,因此,为了更好地了解玉米响应干旱胁迫的分子机制,本研究以2个抗旱性不同的玉米杂交种(耐旱型‘农单476’和敏感型‘众信978’)为材料从玉米8叶至12叶(V12)进行为期12 d的田间干旱胁迫处理,利用蛋白质组学分析玉米叶片在V12时期响应干旱胁迫的差异蛋白。结果表明:干旱胁迫处理后,相比敏感型‘众信978’,耐旱型‘农单476’体内较少蛋白发生差异表达。‘农单476’差异表达蛋白的KEGG富集分析表明内质网蛋白质加工途径是玉米在V12时期防御和响应干旱胁迫的关键通路。‘众信978’差异表达蛋白的KEGG富集分析表明核糖体蛋白的变化是受干旱胁迫影响的最基本也是关键的生物学过程之一。本研究结果进一步明确了玉米V12期响应干旱胁迫调控机制,为今后的定向克隆奠定了基础,也为抗旱新品种的分子设计育种提供了基础。

Drought was the main abiotic stress factor that limits maize growth and yield,and drought tolerance of maize was a quantitative trait controlled by multiple genes.Hence,in this study,two maize hybrids(‘Nongdan476’and‘Zhongxin978’)with different drought resistance were used as materials exposed to field drought stress for 12 days from the maize 8-leaf-age stage to the maize 12-leaf-age stage(V12),in order to better understand the molecular mechanism of maize response to drought stress.The differentially abundant proteins(DAPs)of the response of maize leaves to the drought stress in the V12 stage were studied by proteomic analysis.The results showed that under drought stress,the leaves had less DAPs in drought-tolerant hybrid‘Nongdan476’than that of sensitive hybrid‘Zhongxin978’.The analysis of KEGG enrichment in‘Nongdan476’indicated that endoplasmic reticulum protein pathway was the key pathway of maize defense and response to drought stress at the V12 stage.The analysis of KEGG enrichment in‘Zhongxin978’showed that the change of ribosomal protein was one of the most basic and key biological processes affected by drought stress.The results of this study deepened our understanding of the regulation mechanism of maize V12 stage in response to drought stress,laid a foundation for directional cloning in the future,and also provided a foundation for molecular design breeding of drought-resistant new varieties.