Abstract

With the increasing public attention to the health benefit of polyunsaturated fatty acids (PUFAs) and demand for linolenic acid (C18:3), it is of great significance to increase the C18:3 content in our meal. As an oil crop with high content of C18:3, Camelina sativa has three homologous copies of FAD2 and three homologous copies FAD3. In this study, we seed-specifically overexpressed two Camelina sativa fatty acid desaturase genes, CsFAD2 and CsFAD3, in rapeseed cultivar Zhongshuang 9. The results show that C18:3 content in CsFAD2 and CsFAD3 overexpressed seeds is increased from 8.62% in wild-type (WT) to 10.62–12.95% and 14.54–26.16%, respectively. We crossed CsFAD2 and CsFAD3 overexpression lines, and stable homozygous digenic crossed lines were obtained. The C18:3 content was increased from 8.62% in WT to 28.46–53.57% in crossed overexpression lines. In addition, we found that the overexpression of CsFAD2 and CsFAD3 had no effect on rapeseed growth, development, and other agronomic traits. In conclusion, we successfully generated rapeseed germplasms with high C18:3 content by simultaneously overexpressing CsFAD2 and CsFAD3, which provides a feasible way for breeding high C18:3 rapeseed cultivars.

中文翻译：

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通过CsFAD2和CsFAD3基因的过表达提高菜籽油中的亚麻酸含量

摘要

随着公众对多不饱和脂肪酸（PUFA）健康益处的日益关注以及对亚麻酸（C18:3）的需求，增加膳食中C18:3的含量具有重要意义。作为C18:3含量高的油料作物，亚麻荠具有3个FAD2同源拷贝和3个FAD3同源拷贝。在本研究中，我们在油菜品种中双9号中种子特异性过表达两个亚麻荠脂肪酸去饱和酶基因CsFAD2和CsFAD3 。结果表明， CsFAD2和CsFAD3过表达种子中的C18:3含量比野生型的8.62%增加（WT）分别为 10.62–12.95% 和 14.54–26.16%。我们将CsFAD2和CsFAD3过表达系进行杂交，获得了稳定的纯合双基因杂交系。C18:3 含量从 WT 中的 8.62% 增加到交叉过表达系中的 28.46-53.57%。此外，我们发现CsFAD2和CsFAD3的过表达对油菜生长、发育和其他农艺性状没有影响。总之，我们通过同时过表达CsFAD2和CsFAD3，成功获得了高C18:3含量的油菜种质，为选育高C18:3油菜品种提供了一条可行的途径。