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Suppression of the microRNA pathway by bacterial effector proteins.

ABSTRACT: Plants and animals sense pathogen-associated molecular patterns (PAMPs) and in turn differentially regulate a subset of microRNAs (miRNAs). However, the extent to which the miRNA pathway contributes to innate immunity remains unknown. Here, we show that miRNA-deficient mutants of Arabidopsis partly restore growth of a type III secretion-defective mutant of Pseudomonas syringae. These mutants also sustained growth of nonpathogenic Pseudomonas fluorescens and Escherichia coli strains, implicating miRNAs as key components of plant basal defense. Accordingly, we have identified P. syringae effectors that suppress transcriptional activation of some PAMP-responsive miRNAs or miRNA biogenesis, stability, or activity. These results provide evidence that, like viruses, bacteria have evolved to suppress RNA silencing to cause disease.

SUBMITTER: Navarro L

PROVIDER: S-EPMC2570098 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Suppression of the microRNA pathway by bacterial effector proteins.

Navarro Lionel L Jay Florence F Nomura Kinya K He Sheng Yang SY Voinnet Olivier O

Science (New York, N.Y.) 20080801 5891

Plants and animals sense pathogen-associated molecular patterns (PAMPs) and in turn differentially regulate a subset of microRNAs (miRNAs). However, the extent to which the miRNA pathway contributes to innate immunity remains unknown. Here, we show that miRNA-deficient mutants of Arabidopsis partly restore growth of a type III secretion-defective mutant of Pseudomonas syringae. These mutants also sustained growth of nonpathogenic Pseudomonas fluorescens and Escherichia coli strains, implicating ...[more]

PMID: 18703740

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