Regulation of miR163 and its targets in defense against Pseudomonas syringae in Arabidopsis thaliana

• Published in: Scientific reports Vol. 7; no. 1; p. 46433
• Main Authors: Chow, Hiu Tung, Ng, Danny W-K.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.04.2017; Nature Publishing Group
• Subjects: 38/15; 38/71; 38/90; 631/208/200; 631/337/384/331; 631/449/1659; 631/449/2661/2666; 82/29; 82/80; Embryogenesis; Embryonic growth stage; Flowering; Genes; Histone deacetylase; Humanities and Social Sciences; miRNA; multidisciplinary; Pathogens; Science; Tomatoes; Transgenic plants
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep46433

Small RNAs are important regulators for a variety of biological processes, including leaf development, flowering-time, embryogenesis and defense responses. miR163 is a non-conserved miRNA and its locus has evolved recently through inverted duplication of its target genes to which they belong to the SABATH family of related small-molecule methyltransferases (MTs). In Arabidopsis thaliana , previous study demonstrated that miR163 accumulation was induced by alamethicin treatment, suggesting its roles in defense response pathways. Enhanced resistance against Pseudomonas syringae pv. tomato (Pst ) was observed in the mir163 mutant, whereas transgenic lines overexpressing miR163 showed increase sensitivity to Pst , suggesting that miR163 is a negative regulator of defense response. Elevated level of miR163 and its targets in A. thaliana were observed upon Pst treatment, suggesting a modulating relationship between miR163 and its targets. In addition, miR163 and histone deacetylase were found to act cooperatively in mediating defense against Pst. Transgenic plants overexpressing miR163-resistant targets suggested their different contributions in defense. Results from this study revealed that the stress-inducible miR163 and its targets act in concert to modulate defense responses against bacterial pathogen in A. thaliana .