Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait  

作　　者：Haoxue Wu Xiaohan Zhang Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 

机构地区：[1]College of Agronomy,Northwest A&F University,Yangling,712100,China

出　　处：《Phyton-International Journal of Experimental Botany》2024年第3期627-640,共14页国际实验植物学杂志（英文）

基　　金：The study was financially supported by Projects from Shaanxi Province(2021LLRH-07-03-01 and 2023-ZDLNY-07);Yangling Seed Industry Innovation(YLzy-yc2021-01).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.

摘　　要：Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes.

关 键 词：Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation 

分 类 号：Q94[生物学—植物学]