Li Shan, Hanlon Regina, Wise Hua, Pal Narinder, Brar Hargeet, Liao Chunyu, Gao Hongyu, Perez Eli, Zhou Lecong, Tyler Brett M, Bhattacharyya Madan K
Department of Agronomy, Iowa State University, Ames, IA, United States.
School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, United States.
Front Plant Sci. 2021 Oct 6;12:725571. doi: 10.3389/fpls.2021.725571. eCollection 2021.
is an oomycete that causes stem and root rot disease in soybean. delivers many RxLR effector proteins, including Avr1b, into host cells to promote infection. We show here that Avr1b interacts with the soybean U-box protein, GmPUB1-1, in yeast two-hybrid, pull down, and bimolecular fluorescence complementation (BIFC) assays. , and a homeologous copy , are induced by infection and encode 403 amino acid proteins with U-Box domains at their N-termini. Non-synonymous mutations in the Avr1b C-terminus that abolish suppression of cell death also abolished the interaction of Avr1b with GmPUB1-1, while deletion of the GmPUB1-1 C-terminus, but not the U box, abolished the interaction. BIFC experiments suggested that the GmPUB1-1-Avr1b complex is targeted to the nucleus. ubiquitination assays demonstrated that GmPUB1-1 possesses E3 ligase activity. Silencing of the genes in soybean cotyledons resulted in loss of recognition of Avr1b by gene products encoded by -b and -k. The recognition of Avr1k (which did not interact with GmPUB1-1) by -k plants was not, however, affected following - silencing. Furthermore, over-expression of GmPUB1-1 in particle bombardment experiments triggered cell death suggesting that GmPUB1 may be a positive regulator of effector-triggered immunity. In a yeast two-hybrid system, GmPUB1-1 also interacted with a number of other RxLR effectors including Avr1d, while Avr1b and Avr1d interacted with a number of other infection-induced GmPUB proteins, suggesting that the pathogen uses a multiplex of interactions of RxLR effectors with GmPUB proteins to modulate host immunity.
是一种卵菌，可导致大豆茎腐病和根腐病。它会将许多RxLR效应蛋白（包括Avr1b）输送到宿主细胞中以促进感染。我们在此表明，在酵母双杂交、下拉和双分子荧光互补（BIFC）实验中，Avr1b与大豆U-box蛋白GmPUB1-1相互作用。 和一个同源拷贝 在感染后被诱导，并编码在其N端具有U-Box结构域的403个氨基酸的蛋白质。Avr1b C端的非同义突变消除了对细胞死亡的抑制，同时也消除了Avr1b与GmPUB1-1的相互作用，而删除GmPUB1-1的C端（而非U盒）则消除了这种相互作用。BIFC实验表明，GmPUB1-1-Avr1b复合物定位于细胞核。泛素化分析表明，GmPUB1-1具有E3连接酶活性。沉默大豆子叶中的 基因导致由 -b和 -k编码的基因产物无法识别Avr1b。然而， -k植物对Avr1k（其不与GmPUB1-1相互作用）的识别在 -沉默后不受影响。此外，在粒子轰击实验中过表达GmPUB1-1会引发细胞死亡，这表明GmPUB1可能是效应子触发免疫的正调节因子。在酵母双杂交系统中，GmPUB1-1还与许多其他RxLR效应子（包括Avr1d）相互作用，而Avr1b和Avr1d与许多其他感染诱导的GmPUB蛋白相互作用，这表明病原体利用RxLR效应子与GmPUB蛋白的多重相互作用来调节宿主免疫。
