A Plant miRNA Contributes to Antibacterial Resistance by Repressing Auxin Signaling

  title={A Plant miRNA Contributes to Antibacterial Resistance by Repressing Auxin Signaling},
  author={Lionel Navarro and Patrice Dunoyer and Florence Jay and Benedict C. Arnold and Nihal Dharmasiri and Mark Estelle and Olivier Voinnet and Jonathan D. G. Jones},
  pages={436 - 439}
Plants and animals activate defenses after perceiving pathogen-associated molecular patterns (PAMPs) such as bacterial flagellin. In Arabidopsis, perception of flagellin increases resistance to the bacterium Pseudomonas syringae, although the molecular mechanisms involved remain elusive. Here, we show that a flagellin-derived peptide induces a plant microRNA (miRNA) that negatively regulates messenger RNAs for the F-box auxin receptors TIR1, AFB2, and AFB3. Repression of auxin signaling… 

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