Genome-wide characterization and expression profiling of diacylglycerol acyltransferase genes from maize.

Diacylglycerol acyltransferase (DGAT) catalyzes the only rate-limiting step in the pathway of plant oil (TAG) biosynthesis and is involved in plant development. In this study, five DGAT family members were identified from maize genome database. Phylogenetic analysis classified the ZmDGATs into type-I, II, and III clusters. Conserved functional domain analysis revealed that the proteins encoded by ZmDGAT1 contained conserved MBOAT domains, while two ZmDGAT2-encoding proteins harbored LPLAT domains. qRT-PCR analysis showed that ZmDGAT genes exhibited very high relative expression in developing seeds, especially at the early stage of seed development. Under various abiotic stress conditions, differential responses of ZmDGAT genes were observed. An overall significant induction of ZmDGAT genes under cold stress in leaves and a quick and strong response to osmotic stresses in roots were highlighted. This study provides useful information for understanding the roles of DGATs in oil accumulation and stress responses in higher plants.