摘要
稻曲病菌在侵染过程中会分泌大量的效应蛋白来帮助其侵染。本研究鉴定到一个稻曲病菌效应蛋白UvSix1-1,同源序列比对及系统发育分析发现其具有Six1蛋白保守的氨基酸位点,并与多个病原菌中的Six1蛋白具有同源性。进一步研究发现UvSix1-1可以抑制Bax、XEG1和INF1引起的烟草叶片细胞坏死,并且其预测的信号肽区域具有分泌功能,在烟草上瞬时表达UvSix1-1可以促进辣椒疫霉的定殖。对不同稻曲菌株中的序列进行分析,没有发现序列多态性,说明该基因非常保守。以上研究结果表明,UvSix1-1在病原菌侵染过程中发挥作用,研究结果为稻曲病菌效应蛋白的研究提供参考。
Ustilaginoidea virens secretes a large number of effectors during infection. We identified a potential effector UvSix1-1 from U. virens,which is the ortholog of Six1 in other pathogens containing conserved amino acid resides by sequence alignment and phylogenetic analysis. A signal peptide predicted in UvSix1-1 was confirmed to be functional in yeast system. Transient expression of UvSix1-1 in Nicotiana benthamiana could suppress Bax-,XEG1-and INF1-induced cell death and promote the colonization of Phytophthora capsici in host cells. Sequence analysis of UvSix1-1 in different strains of U. virens revealed no sequence polymorphism. All the results indicate that UvSix1-1 plays a role in the infection process of U. virens and would be a useful model for the study on effectors of U. virens and other pathogens.
引文
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