Abstract:In this study, we acquired two MtDGAT1 genes (MtDGAT11 and MtDGAT12) from cDNA of Medicago truncatula by using insilico cloning combined with RTPCR. The length of MtDGAT11 is 1 620 bp, encoding 539 amino acids, while the length of MtDGAT12 is 1 524 bp, encoding 507 amino acids. Multiple alignments revealed that both MtDGAT11 and MtDGAT12 shared the typical functional motifs with DGAT1s from other plant species. Expression analysis showed that both MtDGAT11 and MtDGAT12 were expressed in root, stem, leaf, flower and seed, and highly expressed in developing seeds; MtDGAT11 was highly expressed in earlymiddle periods of seed development, while MtDGAT12 was highly expressed in the middle and later periods of seed development. Functional complementation in yeast H1246 confirmed that MtDGAT11 encodes disfunctional DGAT and MtDGAT12 encodes functional DGAT.