Linum usitatissimum FAD2A and FAD3A enhance seed polyunsaturated fatty acid accumulation and seedling cold tolerance in Arabidopsis thaliana
Linum usitatissimum FAD2A and FAD3A enhance seed polyunsaturated fatty acid accumulation and seedling cold tolerance in Arabidopsis thaliana
复制标题
DOI：
10.1016/j.plantsci.2021.111014
复制
发表时间：
2021-08-14
期刊：
影响因子：
5.2
通讯作者：
Chen, Mingxun
中科院分区：
文献类型：
--
作者：
Wang, Jianjun;Liu, Zijin;Chen, Mingxun
亚麻 (Linum usitatissimum) 籽油富含多不饱和脂肪酸 (PUFA)，特别是由亚油酸转化而来的亚麻酸。研究表明，亚油酸和亚麻酸的生物合成分别受FAD2和FAD3控制。然而，来自 L. usitatissimum 的不同 LuFAD2 和 LuFAD3 拷贝分别在控制亚油酸或亚麻酸生物合成方面的功能差异仍不清楚。本研究从油菜品种‘龙牙10’中克隆了5个LuFAD2和3个LuFAD3 cDNA，GC-MS结果表明LuFAD2A和LuFAD3A分别在亚油酸和亚麻酸的积累中起主导作用。它们在拟南芥种子中同时过度表达导致脂肪酸含量显着增加，尤其是多不饱和脂肪酸。此外，LuFAD2A和LuFAD3A通过增加亚麻酸水平来促进茉莉酸的生物合成，从而增强植物的耐寒性。当亚麻酸含量不足时，植物通过花青素的积累来适应低温。这些发现为了解 L. usitatissimum 种子中 PUFA 的较高积累提供了见解，并为通过分子操作改善其他产油作物的油质量提供了潜在目标。
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.