Conserved Function of ACYL-ACYL CARRIER PROTEIN DESATURASE 5 on Seed Oil and Oleic Acid Biosynthesis between and .

Previous studies have shown that several ACYL-ACYL CARRIER PROTEIN DESATURASE (AtAAD) members in are responsible for oleic acid (C18:1) biosynthesis. Limited research has been conducted on another member, AtAAD5, and its paralog BnAAD5 in the closely related and commercially important plant, . Here, we found that was predominantly and exclusively expressed in developing embryos at the whole seed developmental stages. The mutation caused a significant decrease in the amounts of oil and C18:1, and a considerable increase in the content of stearic acid (C18:0) in mature seeds, suggesting that AtAAD5 functioned as an important facilitator of seed oil biosynthesis. We also cloned the full-length coding sequence of from the A3 subgenome of the inbred line L111. We showed that ectopic expression of in the mutant fully complemented the phenotypes of the mutant, such as lower oil content and altered contents of C18:0 and C18:1. These results help us to better understand the functions of AAD members in and and provide a promising target for genetic manipulation of .