基于iTRAQ技术的甘蔗受黑穗病菌侵染蛋白组分析

Proteomic analysis of sugarcane-Sporisorium scitamineum interaction based on iTRAQ technique

黑穗病已成为影响甘蔗产量和含糖量的重要病害。为从蛋白质水平探讨甘蔗应答黑穗病菌的分子机制,本实验选用抗黑穗病品种桂糖29号和感黑穗病品种崖城71-374,处理组用浸渍法接种黑穗病菌,对照组用无菌水模拟接菌,在接种180 d后采取甘蔗叶片,使用iTRAQ技术对蛋白质组进行研究。结果显示,桂糖29号中有定量信息蛋白1429个,差异表达蛋白290个,其中上调表达蛋白153个,下调表达蛋白137个;崖城71-374中有定量信息蛋白1576个,差异表达蛋白125个,其中上调表达蛋白55个,下调表达蛋白70个。抗病品种桂糖29号中差异表达蛋白数多于感病品种崖城71-374,且桂糖29号在KEGG富集到的代谢通路也更多,可能被侵染后抗病品种的免疫调节机制更为复杂,涉及的调控通路网更广。经对光合作用、抗氧化系统、钙信号、苯丙烷类代谢、激素相关差异表达蛋白及共有差异表达蛋白分析,发现光合作用通路、ROS、ABA、钙信号通路相关蛋白在2个品种中多为上调表达,且桂糖29号的上调表达蛋白数多于崖城71-374,可能参与甘蔗后期对黑穗病的应答。植物抗病是一个复杂的过程,需要多种功能与途径参与调控。在本实验中没有发现苯丙烷类代谢途径及一些酶(谷胱甘肽过氧化物酶、抗坏血酸过氧化物酶、超氧化物歧化酶、谷胱甘肽硫转移酶、过氧化氢酶)、激素(生长素、乙烯、赤霉素)参与甘蔗的抗病过程,可能与采样时间有关。

Sugarcane smut has become an important disease affecting sugarcane yield and sugar content.In order to investigate the molecular mechanism of sugarcane responding to smut at protein level,the smut-resistant variety GT29and the smut-susceptible variety Yacheng71-374were used in this study.Both varieties were inoculated with the teliospore suspension of smut pathogen by dipping method whereas the control was treated with sterile water.Leaf samples were collected and used for proteomic analysis by iTRAQ technique at180days after treatment.The that1429proteins presented in GT29with quantitative information,including290differentially expressed proteins with153up-regulated and137down-regulated;while1576proteins in Yacheng71-374with quantitative information,including125differentially expressed proteins with55up-regulated and70down-regulated.The number of differentially expressed proteins in resistant variety was higher than that in susceptible variety,and GT29enriched more metabolic pathways in KEGG,indicating that the immunomodulatory mechanism of the resistant variety may be more complicated,and the regulatory network involved in response was broader.Through the analysis of photosynthesis,antioxidant system,calcium signal,phenylpropane metabolism,hormone related differential expressed protein and co-owned differentially expressed protein,it was found that the photosynthesis pathway,ROS,ABA,calcium signal pathway related protein were up-regulated in both varieties.The up-regulated expressed proteins were more in GT29than in Yacheng71-374,which may be involved in resistance response in sugarcane against smut pathogen at later growth stage.Plant disease resistance is a complex process that requires multiple functions and pathways to participate in regulation.The phenylpropanoid metabolic pathway,enzymes GPX,APX,SOD,GST,and CAT,and hormones IAA,ETH,and GA were not found to be involved in the disease resistance process of sugarcane.