In Silico Analysis of Fatty Acid Desaturases Structures in Camelina sativa, and Functional Evaluation of Csafad7 and Csafad8 on Seed Oil Formation and Seed Morphology

Abstract

Fatty acid desaturases add a second bond into a single bond of carbon atoms in fatty acid chains, resulting in an unsaturated bond between the two carbons. They are classified into soluble and membrane-bound desaturases, according to their structure, subcellular location, and function. The orthologous genes in Camelina sativa were identified and analyzed, and a total of 62 desaturase genes were identified. It was revealed that they had the common fatty acid desaturase domain, which has evolved separately, and the proteins of the same family also originated from the same ancestry. A mix of conserved, gained, or lost intron structure was obvious. Besides, conserved histidine motifs were found in each family, and transmembrane domains were exclusively revealed in the membrane-bound desaturases. The expression profile analysis of C. sativa desaturases revealed an increase in young leaves, seeds, and flowers. C. sativa ω3-fatty acid desaturases CsaFAD7 and CsaDAF8 were cloned and the subcellular localization analysis showed their location in the chloroplast. They were transferred into Arabidopsis thaliana to obtain transgenic lines. It was revealed that the ω3-fatty acid desaturase could increase the C18:3 level at the expense of C18:2, but decreases in oil content and seed weight, and wrinkled phenotypes were observed in transgenic CsaFAD7 lines, while no significant change was observed in transgenic CsaFAD8 lines in comparison to the wild-type. These findings gave insights into the characteristics of desaturase genes, which could provide an excellent basis for further investigation for C. sativa improvement, and overexpression of ω3-fatty acid desaturases in seeds could be useful in genetic engineering strategies, which are aimed at modifying the fatty acid composition of seed oil.

Identification and Investigation of the Genetic Variations and Candidate Genes Responsible for Seed Weight via GWAS in Paper Mulberry

“…and the seeds of GmFAD3 -silenced plants are larger and heavier in soybean [ 48 ]. The seed weight and oil content of CsaFAD7 and CsaFAD8 transgenic lines are decreased in Arabidopsis thaliana , and the result shows that FAD genes could affect the seed morphology [ 49 ]. Previous studies have shown that cold-tolerant plants contain higher levels of unsaturated fatty acids, and FAD is involved in the cold stress response [ 50 ].…”

Class A lysophosphatidic acid acyltransferase 2 from Camelina sativa promotes very long‐chain fatty acids accumulation in phospholipid and triacylglycerol

“…The seed size was measured using 5–10 mg of dry seeds, which were well spread on a plate to observe visible and distinguished individual grains. Next, the seeds were scanned with Unis D6810 (WSeen Detection Technology Co., Ltd, Hangzhou, China), and the seed size was automatically calculated by the SC‐G grain appearance quality image analysis system developed by Hangzhou WSeen Detection Technology Co., Ltd (Raboanatahiry et al., 2021).…”