DOG1 role in BRM SWI/SNF complex mediated control of seed quality and physiology
The SWI/SNF chromatin remodeling complex is involved in various aspects of plant development and stress responses. In this study, we investigated the role of BRM, a core subunit of the SWI/SNF complex, in seed physiological quality in Arabidopsis thaliana. We found that brm-3 seeds exhibited enlarged size, reduced yield, increased longevity, and enhanced secondary dormancy, but no change in primary dormancy or salt tolerance. We also showed that some of these phenotypes were dependent on DOG1, a key regulator of seed dormancy, as they were reversed in the brm-3xdog1-4 double mutant. Transcriptomic and metabolomic analyses revealed that BRM and DOG1 synergisticly modulate the expression of majority genes and metabolites. In contrast some of the transcriptomic and metabolomic changes including glutathione were depended on DOG1. Moreover, we demonstrated that BRM controls secondary dormancy directly through DOG1 by binding to and remodeling its 3' region, where an antisense promoter of DOG1 is located. Our results suggest that BRM and DOG1 cooperate to control seed physiological quality by fine-tuning the chromatin state and metabolic status of seeds. This study provides new insights into the molecular mechanisms of seed dormancy and longevity, and the interplay between chromatin remodelling at DOG1 locus. Overall design: Comparison of Col-0, dog1-4, brm-3 and double brm-3 x dog1-4 mutants dry seed transcriptomes (four biological replicas).