Katiyar-Agarwal Surekha, Morgan Rebekah, Dahlbeck Douglas, Borsani Omar, Villegas Andy, Zhu Jian-Kang, Staskawicz Brian J, Jin Hailing
Department of Plant Pathology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA.
Proc Natl Acad Sci U S A. 2006 Nov 21;103(47):18002-7. doi: 10.1073/pnas.0608258103. Epub 2006 Oct 27.
RNA interference, mediated by small interfering RNAs (siRNAs), is a conserved regulatory process that has evolved as an antiviral defense mechanism in plants and animals. It is not known whether host cells also use siRNAs as an antibacterial defense mechanism in eukaryotes. Here, we report the discovery of an endogenous siRNA, nat-siRNAATGB2, that is specifically induced by the bacterial pathogen Pseudomonas syringae carrying effector avrRpt2. We demonstrate that the biogenesis of this siRNA requires DCL1, HYL1, HEN1, RDR6, NRPD1A, and SGS3. Its induction also depends on the cognate host disease resistance gene RPS2 and the NDR1 gene that is required for RPS2-specified resistance. This siRNA contributes to RPS2-mediated race-specific disease resistance by repressing PPRL, a putative negative regulator of the RPS2 resistance pathway.
由小干扰RNA(siRNA)介导的RNA干扰是一种保守的调控过程,在植物和动物中已演变成一种抗病毒防御机制。目前尚不清楚宿主细胞在真核生物中是否也将siRNA用作抗菌防御机制。在此,我们报告发现了一种内源性siRNA,即nat-siRNAATGB2,它由携带效应子avrRpt2的细菌病原体丁香假单胞菌特异性诱导产生。我们证明这种siRNA的生物合成需要DCL1、HYL1、HEN1、RDR6、NRPD1A和SGS3。其诱导还依赖于同源宿主抗病基因RPS2以及RPS2介导的抗性所需的NDR1基因。这种siRNA通过抑制PPRL(RPS2抗性途径的一种假定负调控因子)来促进RPS2介导的小种特异性抗病性。