Arabidopsis miRNA boosts host immunity against Verticillium dahliae via repression of plant target gene transcript
M. VAN DAMME (1), G. van den Berg (1), L. Faino (1), B. Thomma (1) (1) Wageningen University, Phytopathology, Netherlands

RNA silencing is a eukaryotic mechanism that exploits small non-coding RNAs (small-RNAs) to regulate gene expression in a sequence-specific manner in many cellular processes, including innate immunity. The plant immune system is a known target of RNA silencing by several pathogens, e.g. viruses and bacteria. The fungus Verticillium dahliae is the causal agent of Verticillium wilt disease. Data from our laboratory indicate that the Arabidopsis thaliana RNA silencing machinery plays a critical role during Verticillium wilt disease (Ellendorff et al., 2009). By combining small-RNA and transcript profiling we identified small-RNAs and their reciprocal target transcripts in V. dahliae-infected A. thaliana plants. Accumulation of a particular A. thaliana miRNA during the interaction, and repression of its reciprocal targeted transcript, causes enhanced resistance to Verticillium wilt disease. We show that A. thaliana T-DNA insertion mutants that lack the target transcript display enhanced resistance to Verticillium wilt disease. Mature miRNAs are generated through multiple processing steps from primary transcripts (pri-miRNA or MIRNA gene) that contain imperfect foldback structures. We are currently analyzing if transgenic A. thaliana lines that overexpress the MIRNA gene also display enhanced resistance to Verticillium wilt disease.

Abstract Number: P17-630
Session Type: Poster