Description
The process of RNA splicing influences many physiological processes including plant immunity. However, how plant parasites manipulate host RNA splicing process remains unknown. Here we demonstrate that PsAvr3c, an avirulence effector from oomycete plant pathogen Phytophthora sojae, physically binds to and stabilizes soybean (Glycine max) serine/lysine/arginine rich proteins GmSKRPs in vivo. The SKRPs are novel proteins that associate with spliceosome components, and are negative regulators of plant immunity. Analysis by RNA-seq data indicates that alternative splicing of pre-mRNAs from 401 soybean genes, including defense related genes, is altered in GmSKRP1 and PsAvr3c over-expressing lines compared to control plants. Representative splicing events mediated by GmSKRP1 and PsAvr3c are tested by infection assays or by transient expression in soybean plants. Our results show that a plant pathogen effector can reprogram host pre-mRNA splicing to promote disease, and we propose that pathogens evolved such strategies to defeat host immune systems. Overall design: three independent soybean SKRP1 over-expression lines, three AVR3C over-expression samples and three GFP control samples