Linum usitatissimum FAD2A and FAD3A enhance seed polyunsaturated fatty acid accumulation and seedling cold tolerance in Arabidopsis thaliana. (October 2021)

• Record Type: Journal Article
• Authors: Wang, Jianjun; Liu, Zijin; Liu, Hua; Peng, Danshuai; Zhang, Jianping; Chen, Mingxun
• Is Part Of: Plant science. Volume 311(2021)
• Publication Date: 2021-10
• Subjects: LuFAD2 -- LuFAD3 -- Fatty acid -- Low temperature -- Jasmonic acid -- Anthocyanins; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2021.111014
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: LuFAD2A and LuFAD3A exhibited predominant roles in the accumulation of linoleic acid and linolenic acid, respectively. Simultaneous overexpression of LuFAD2A and LuFAD3A in A. thaliana seeds significantly increased polyunsaturated fatty acid contents. LuFAD2A and LuFAD3A coordinated the content of anthocyanins and JA in response to low temperature in A. thaliana leaves. Abstract: Flax ( Linum usitatissimum ) seed oil is rich in polyunsaturated fatty acids (PUFAs), particularly linolenic acid, which is converted from linoleic acid. Studies have indicated that the biosynthesis of linoleic acid and linolenic acid is controlled by FAD2 and FAD3, respectively. However, the functional distinctions of different LuFAD2 and LuFAD3 copies from L. usitatissimum in governing the biosynthesis of linoleic acid or linolenic acid, respectively, remain unclear. In this study, five LuFAD2 and three LuFAD3 cDNAs were cloned from the L. usitatissimum cultivar 'Longya 10', and GC–MS results demonstrated that LuFAD2A and LuFAD3A play predominant roles in the accumulation of linoleic acid and linolenic acid, respectively. Their simultaneous overexpression in Arabidopsis thaliana seeds led to a significant increase in fatty acid contents, especially PUFAs. Additionally, LuFAD2A and LuFAD3A promoted the biosynthesis of jasmonic acid by increasing the levels of linolenic acid, which, in turn, enhanced plant cold tolerance. When the amount of linolenic acid is not sufficient, plants adapt to low temperature via the accumulation of anthocyanins. These findings provide insights into the higher accumulation of PUFAs in L. usitatissimum seeds, and provide potential targets for improving oil quality of other oil-producing crops through molecular manipulation.