沼泽红假单胞菌蛋白Rhp-PSP对烟草花叶病毒的系统抗性诱导及互作蛋白筛选

本文研究了蛋白Rhp-PSP诱导烟草抗TMV过程中相关防御酶的活性以及丙二醛（MDA）含量的变化,同时测定了抗病相关基因的表达情况。试验证明,蛋白Rhp-PSP处理烟草后,叶片中苯丙氨酸解氨酶（PAL）、过氧化物酶（POD）和多酚氧化酶（PPO）的活性显著提高,但降低了MDA含量。同时基因PR-1、PR-3、PR-5、PDF1.2表达显著上调,证明了蛋白Rhp-PSP具有诱导烟草产生抗TMV的活性。为阐明诱导抗性机制,利用酵母双杂交系统从烟草cDNA文库进行互作蛋白的筛选并验证,结果表明GPI锚定蛋白、VAN3结合蛋白及叶绿素结合蛋白A与蛋白Rhp-PSP互作。

Systemic Resistance to Tobacco Mosaic Virus (TMV) Induced by Protein Rhp-PSP of Rhodopseudomonas palustris and Screening of Interaction Protein

The activity of defense enzymes, content of malondialdehyde (MDA) and expression level of resistance gene were determined in TMV inoculated tobacco plants induced by protein Rhp-PSP systemic resistance to TMV. The results showed that protein Rhp-PSP treatment increased the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO) in TMV inoculated tobacco leaves, but decreased the content of MDA, and up-regulated the gene expression of PR-1, PR-3, PR-5 and PDF1.2 significantly. The above results indicated that protein Rhp-PSP of Rhodopseudomonas palustris could induce systemic resistance to TMV in tobacco. In order to understand the mechanism of induce systemic resistance, the interaction proteins with protein Rhp-PSP were screened in the tobacco cDNA library using yeast two-hybrid system. The result showed that the GPI anchoring protein, VAN3 binding protein, chlorophyll binding protein A may have interaction with Rhp-PSP.