摘要
Jacalin-related lectins(JRLs)是一种含有Jacalin结构域的植物凝集素,在植物应对生物胁迫和非生物胁迫过程中发挥重要作用。根据其糖结合特性被划分为半乳糖特异性JRL(gJRLs)和甘露糖或葡萄糖特异性JRL(mJRLs)两类。前期研究表明普通小麦TaJRL53编码一个具有Jacalin结构域和Dirigent结构域的蛋白,并能在赤霉菌的诱导下上调表达。由赤霉菌侵染引起的小麦赤霉病是一种毁灭性的病害,它不仅能够导致大幅度减产,而且使感病的麦粒品质下降。受真菌毒素污染的籽粒,严重影响人畜健康。为分析该基因在抗赤霉病方面的作用,本研究利用VIGS系统在小麦中沉默TaJRL53,导致了其对赤霉病的抗性减弱。通过基因枪的方法将该基因的过量表达载体导入到感赤霉病小麦品种中,增强了赤霉病抗性,其病小穗数,病轴长都明显缩短。在赤霉菌侵染后,ROS合成途径相关基因、JA信号通路中的主要标志基因、JA合成基因及病程相关蛋白基因在TaJRL53过量表达的转基因植株中明显高于它们在野生型中的表达量,因此推测TaJRL53提高小麦赤霉病抗性可能跟ROS和JA合成,JA信号转导途径有关。本研究增进了对小麦JRLs家族基因功能的了解,为解析TaJRL53抗赤霉病机制奠定了基础。
Jacalin-related lectins(JRLs)are a group of plant lectins with jacalin protein domain,which play important roles during plant response to biotic and abiotic stress.According their carbohydrate binding specificities,the JRLs were described as two types:galactose-binding acalins(gJRLs)and mannose-binding jacalins(mJRLs).Previous studies have shown that TaJRL53 encodes a protein with Jacalin and Dirigent domains and can be up-regulated by Fusarium graminearum infection.Wheat FHB induced by this pathogen is a disastrous disease,which not only reduces the grain yield,but also contains deoxynivalenol and other toxins,which seriously affect the health of human and livestock.To dissect the gene’s function in FHB resistance,we silenced and overexpressed the TaJRL53 in wheat respectively.As a result,attenuating TaJRL53 increased susceptibility to Fusarium graminearum.And susceptible wheat transformed with TaJRL53 over-expression showed higher Fusarium head blight resistance,the number of diseased spikelets(NDS)and length of diseased spike rachis(LDR)of transgenics wheat with TaJRL53 overexpression were significantly reduced than those of wild type.After Fusarium graminearum infection,the expression of ROS synthesis pathway,JA synthesis and signaling pathways marker genes,and disease related genes in TaJRL53 over-expression transgenic plants were higher than those in non-transgenic control.These results suggest that TaJRL53 enhanced the FHB resistance in wheat through regulating ROS synthesis pathway and JA signal transduction pathways.This study enhanced the understanding of wheat JRLs family genes’function and laid a foundation for the mechanism dissection of TaJRL53 resistant to FHB in wheat.
作者
陈同睿
罗艳君
赵潘婷
贾海燕
马正强
CHEN Tong-Rui;LUO Yan-Jun;ZHAO Pan-Ting;JIA Hai-Yan;MA Zheng-Qiang(College of Agriculture,Nanjing Agricultural University/State Key Laboratory for Crop Genetics and Germplasm Enhancement/Jiangsu Collaborative Innovation Center for Modern Crop Production,Nanjing 210095,Jiangsu,China)
出处
《作物学报》
CAS
CSCD
北大核心
2021年第1期19-29,共11页
Acta Agronomica Sinica
基金
国家重点研发计划项目(2016YFD0101004)资助。
