番茄抗病毒基因Tm-2~2及其等位基因tm-2氨基酸差异分析

番茄抗病蛋白Tm-2~2与其等位感病蛋白tm-2在序列上相对保守但也有一定的差异性,研究这些差异对于了解Tm-2~2抗病蛋白的结构和功能起着重要作用。本研究构建了不同的Tm-2~2/tm-2置换突变体,在本生烟草上利用农杆菌注射法共表达突变体及其效应因子MP或TMV-GFP载体。通过对植物坏死表型以及病毒量变化的观察,发现当Tm-2~2ARC结构域中RNBS-D保守基序中的第413位甘氨酸突变成tm-2中的丝氨酸后,Tm-2~2介导的对烟草花叶病毒属病毒的抗性减弱。这说明RNBS-D保守基序对于Tm-2~2行使其抗病功能是至关重要的。

The analysis of amino acid differences between tomato Tm-22 resistance gene and its alleles tm-2

Tomato resistance protein Tm-2² and its susceptible protein tm-2 are highly conserved but also have some differences. Their difference analysis will help to understand the structure and function of Tm-2². In this study, different Tm-2²/tm-2 replacement mutants were constructed and expressed with its effector MP or TMV-GFP in Nicotiana benthamiana leaves by agro-infiltration approach. By checking the necrosis phenotype and viral accumulation, we found that Tm-2²-mediated resistance against tobamoviruses was weakened when the 413th glycine in the conserved RNBS-D motif within Tm-2² ARC domain was mutated into serine that is the 413th amino acid in tm-2. This finding suggests that the conserved RNBS-D motif is important for Tm-2²-mediated resistance against viruses.