Comparative metabolomic analysis of wild type and mads3 mutant rice anthers

Rice (Oryza sativa L.) MADS3 transcription factor regulates the homeostasis of reactive oxygen species (ROS) during late anther development, and one MADS3 mutant, mads3-4, has defective anther walls, aborted microspores and complete male sterility. Here, we report the untargeted metabolomic analysis of both wild type and mads3-4 mature anthers. Mutation of MADS3 led to an unbalanced redox status and caused oxidative stress that damages lipid, protein, and DNA. To cope with oxidative stress in mads3-4 anthers, soluble sugars were mobilized and carbohydrate metabolism was shifted to amino acid and nucleic acid metabolism to provide substrates for the biosynthesis of antioxidant proteins and the repair of DNA. Mutation of MADS3 also affected other aspects of rice anther development such as secondary metabolites associated with cuticle, cell wall, and auxin metabolism. Many of the discovered metabolic changes in mads3-4 anthers were corroborated with changes of expression levels of corresponding metabolic pathway genes. Altogether, this comparative metabolomic analysis indicated that MADS3 gene affects rice anther development far beyond the ROS homeostasis regulation.