发病相关蛋白(PR)在植物防御反应和系统获得性抗性(SAR)中起重要作用。PR1对许多植物病原体具有抗真菌活性。在我们之前的研究中,对抗小麦品系TcLr19和敏感小麦品种中国春季接种了小麦锈菌(Pt)品种PHNT进行了RNA测序(RNA-seq)。在这项研究中,在RNA-seq文库中发现了七个水杨酸(SA)诱导的与植物抗病性有关的TaPR1基因。定量PCR(qPCR)结果表明,在这七个TaPR1基因中,TaPR1-4在不相容相互作用中被Pt诱导的最多。酵母双杂交(Y2H)结果表明,TaPR1-4通过αIV螺旋与TaTLP1相互作用。体内蛋白质介导的表型测定和体外抗真菌活性表明,与对照叶片相比,用纯TaPR1-4蛋白浸润的小麦叶片发生的病害明显减少。这种效应与防御基因表达的强烈增加有关,并且抗性活性取决于位于TaPR1-4C末端区域的CAPE1基序。这些发现增加了有关TaPR1和TaTLP1相互作用的最新知识,并为TaPR1蛋白在小麦对Pt的抗性中的作用提供了新的见解。
Pathogenesis-related (PR) proteins play important roles in plant defense response and systemic acquired resistance (SAR). PR1 has antifungal activity against many plant pathogens. In our previous study, RNA sequencing (RNA-seq) was conducted on resistant wheat line TcLr19 and sensitive wheat cultivar Chinese Spring inoculated with Puccinia triticina (Pt) race PHNT. In this study, seven salicylic acid (SA)-induced TaPR1 genes involved in plant disease resistance were found in the RNA-seq library. Quantitative PCR (qPCR) results showed that TaPR1-4 was most induced by Pt among these seven TaPR1 genes in the incompatible interaction. Yeast two-hybrid (Y2H) results showed that TaPR1-4 interacted with TaTLP1 via the αIV helix. Protein-mediated phenotyping assays in vivo and antifungal activity in vitro demonstrated that wheat leaves infiltrated with pure TaPR1-4 protein developed significantly less disease compared to control leaves. This effect was correlated with a strong increase in defense gene expression, and resistance activity was dependent on the
CAPE1 motif located in the C-terminal region of TaPR1-4. These findings increase current knowledge regarding the interaction of TaPR1 and TaTLP1 and provide new insights on the role of TaPR1 protein in the resistance of wheat to Pt.