A GWAS-identified U-box E3 ligase MsPUB6 is positively regulated by MsDREB1C and contributes to drought tolerance in alfalfa.

ABSTRACT: U-box-type E3 ubiquitin ligases (PUBs) are critical for signaling homeostasis and abiotic stress responses via substrate ubiquitination, yet their upstream transcriptional regulation remains largely unexplored, especially in alfalfa drought adaptation. Through a genome-wide association study (GWAS) of 171 alfalfa accessions, we identified a novel U-box gene, MsPUB6, on chromosome 3, which encodes a protein with E3 ubiquitin ligase activity and is induced by drought, cold, salt, and abscisic acid. Overexpression and virus-induced gene silencing (VIGS) revealed that MsPUB6 positively regulates drought tolerance by enhancing antioxidant enzymes (SOD and CAT), reducing malondialdehyde (MDA) and reactive oxygen species (ROS) levels, and maintaining chlorophyll content and leaf water content. Fu

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC13650487 | biostudies-literature | 2026 Oct

REPOSITORIES: biostudies-literature