Mutations across diverse domains of ShXDR1 lead to multi-drug resistance in Clarireedia jacksonii.

Recently, Clarireedia spp. has emerged as a significant pathogen threatening turfgrass and the escalating resistance to multi-drugs in Clarireedia spp. often fails field interventions. Genetic investigations have identified the crucial involvement of the transcription factor ShXDR1T853 in regulating multi-drug resistance (MDR) in C. jacksonii. Our sequence analysis unveiled five additional mutations in ShXDR1-G445D, K453E, S607F, D676H, and V690A. This study revealed that all five mutations with gain-of-function (GOF) were confirmed to directly contribute to MDR against three different fungicide classes (propiconazole: demethylation inhibitor, boscalid: succinate dehydrogenase inhibitor, and iprodione: dicarboximide) using genetic transformation system and in vitro drug-sensitivity assay. Comparative transcriptome analysis revealed distinct expression profiles of drug-related genes in ShXDR1 alleles with various GOF mutations.