Yan Min, Jing Wen, Xu Ni, Shen Like, Zhang Qun, Zhang Wenhua
College of Life Sciences, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, P. R. China.
Funct Plant Biol. 2016 Mar;43(3):221-231. doi: 10.1071/FP15090.
Reactive oxygen species (ROS) play a key signalling role in cells. Plant NADPH oxidases, also known as respiratory burst oxidase homologues (Rbohs), are well characterised ROS-generating systems. In this study, we found that the constitutively active small guanosine triphosphatase (GTPase) ROP11 (CA-ROP11) interacted with RbohF by using a yeast two-hybrid analysis, a pull-down assay and an in vivo bimolecular fluorescence complementation assay. The mutation of amino acid L336 or L337 in RbohF abolished its interaction with CA-ROP11. Coexpression of CA-ROP11 and wild-type RbohF in Nicotiana benthamiana Domin enhanced ROS production compared with coexpression of CA-ROP11 and mutant RbohF or of dominant negative ROP11 and wild-type RbohF. Moreover, CA-ROP11 overexpression resulted in ROS accumulation and a swollen root hair phenotype in Arabidopsis thaliana (L.) Heynh. The deletion of RbohF partially reduced the increase in ROS in Arabidopsis plants overexpressing CA-ROP11. These results suggest that Arabidopsis ROP11 modulates ROS production by interacting with RbohF in root hairs.
活性氧（ROS）在细胞中发挥关键的信号传导作用。植物NADPH氧化酶，也称为呼吸爆发氧化酶同源物（Rbohs），是特征明确的ROS生成系统。在本研究中，我们通过酵母双杂交分析、下拉试验和体内双分子荧光互补试验发现，组成型活性小GTP酶（GTPase）ROP11（CA-ROP11）与RbohF相互作用。RbohF中氨基酸L336或L337的突变消除了其与CA-ROP11的相互作用。与CA-ROP11和突变型RbohF共表达或显性负性ROP11和野生型RbohF共表达相比，在本氏烟草中CA-ROP11和野生型RbohF共表达增强了ROS的产生。此外，CA-ROP11过表达导致拟南芥中ROS积累和根毛肿胀表型。RbohF的缺失部分降低了过表达CA-ROP11的拟南芥植物中ROS的增加。这些结果表明，拟南芥ROP11通过与根毛中的RbohF相互作用来调节ROS的产生。
