RT Journal Article
SR Electronic
T1 Oomycete small RNAs invade the plant RNA-induced silencing complex for virulence
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 689190
DO 10.1101/689190
A1 Florian Dunker
A1 Adriana Trutzenberg
A1 Jan Samuel Rothenpieler
A1 Sarah Kuhn
A1 Reinhard Pröls
A1 Tom Schreiber
A1 Alain Tissier
A1 Ralph Hückelhoven
A1 Arne Weiberg
YR 2019
UL http://biorxiv.org/content/early/2019/07/02/689190.abstract
AB Fungal small RNAs (sRNAs) hijack the plant RNA silencing pathway to manipulate host gene expression, named cross-kingdom RNA interference (ckRNAi). It is currently unknown how conserved and significant ckRNAi is for microbial virulence. Here, we found for the first time that sRNAs of a pathogen representing the oomycete kingdom invade the host plant’s Argonaute (AGO)/RNA-induced silencing complex. To demonstrate the functionality of the plant-invading oomycete Hyaloperonospora arabidopsidis sRNAs (HpasRNAs), we designed a novel CRISPR endoribonuclease Csy4/GUS repressor reporter to visualize in situ pathogen-induced target suppression in Arabidopsis thaliana host plant. By using 5’ RACE-PCR we demonstrated HpasRNAs-directed cleavage of plant mRNAs. The significant role of HpasRNAs together with AtAGO1 in virulence was demonstrated by plant atago1 mutants and by transgenic Arabidopsis expressing a target mimic to block HpasRNAs, that both exhibited enhanced resistance. Individual HpasRNA plant targets contributed to host immunity, as Arabidopsis gene knockout or HpasRNA-resistant gene versions exhibited quantitative enhanced or reduced susceptibility, respectively. Together with previous reports, we found that ckRNAi is conserved among oomycete and fungal pathogens.