在植物中，超长链脂肪酸具有广泛的生理生化功能，它是角质层蜡质生物合成的前体物质，还参与了甘油酯、生物膜膜脂及鞘脂的合成，但其在复叶发育中的功能仍然未知。蒺藜苜蓿是豆科模式植物，也是复叶研究的新模式植物。为了研究其在复叶发育中的功能，我们筛选了约22，000个突变体株系并分离出蒺藜苜蓿超长链脂肪酸合成和角质层形成关键基因MtFIDDLEHEAD （MtFDH），Mt3-KETOACYL-COA SYNTHASE12（MtKCS12）和MtABERRANT INDUCTION OF TYPE THREE 1（MtATT1）的缺失突变体。在本项目中，我们拟对MtFDH，MtATT1和MtKCS12参与的超长链脂肪酸合成和角质层形成在复叶发育中的功能开展系统研究。这一项目将首次阐明超长链脂肪酸在复叶模式形成和叶片发育中的作用机制，相关研究结果将对近缘牧草紫花苜蓿的品质改良提供新的研究思路。

Very long chain fatty acids （VLCFAs）are involved in many biochemical and physiological processes in plants. They are not only related with the biosynthesis of triacylglycerols, membrane lipids, and sphingolipids, but also are the precursors of wax layer compounds of cuticle. However, the function of VLCFAs in compound leaf development is largely unknown. As the legume species, Medicago truncatula is recognized as the new model species for compound leaf study. To study the roles of VLCFAs, about 22,000 independent lines of Tnt1 retrotransposon-tagged M. truncatula populations were screened. The mutants of MtFIDDLEHEAD（MtFDH）, Mt3-KETOACYL-COA SYNTHASE12（MtKCS12） and MtABERRANT INDUCTION OF TYPE THREE 1（MtATT1）were isolated. MtFDH, MtKCS12 and MtATT1 are involved in the VLCFAs biosynthesis and cutin formation. This project is proposed to study the roles of VLCFAs and cutin in compound leaf pattern and leaflet development, which will provide the insights for the quality improvement of important forage alfalfa.