电压依赖性阴离子通道VDAC3参与拟南芥先天免疫

Arabidopsis VDAC3 participates in innate im m unity

线粒体外膜蛋白电压依赖性阴离子通道(VDAC)是动物细胞凋亡调控系统中的关键组分,但其在植物中的功能还不明确。拟南芥VDAC家族有4个成员,它们都能被病原菌诱导,VDAC1在由病原菌所引起的超敏性细胞死亡中发挥作用已有报道,但VDAC家族其他成员是否参与植物免疫反应还未见报道。本研究以拟南芥相关T-DNA插入突变体为材料,研究了VDAC3基因在植物抗病反应中的功能。病原相关分子模式flg22诱导的活性氧产生和胼胝质沉积在VDAC3突变体中都显著增强,表明VDAC3参与了病原相关分子模式触发的免疫反应。此外,效应因子激发的超敏性细胞死亡在vdac3突变体中也更明显,显示VDAC3也参与了效应子触发的免疫反应。以上结果说明,VDAC3在多个层面参与植物的抗病反应。

Mitochondrial outer membrane protein voltage-dependent anion channels （VDACs） play crucial roles in mammalian apoptosis. However, the functions of VDACs in plants still need to be established. In Arabidopsis thaliana genome there are four VDAC genes and all the four VDAC genes are up-regulated by pathogen treatments. Previous studies revealed that Arabidopsis VDAC1 and VDAC4 are probably involved in hypersensi- tive cell death. Nonetheless, whether other VDAC members also involved in Arabidopsis immunity is still unclear. In this study, roles of VDAC3 in immunity were explored with T-DNA insertion mutants. The PAMP flg22-induced ROS bursts and callose deposition were both increased in vdac3 mutants. Interestingly, effectortriggered hypersensitive cell death is also enhanced in vdac3 mutants. These results indicated that Arabidopsis VDAC3 negatively regulates both PAMP-triggered immunity （grI） and effector-triggered immunity （ETI）.