NingZhang, LinChen, Shuai Ma, RuofanWang, Qiong He, MinTian， Lugang Zhang. Fine mapping and candidate gene analysis of the white flower gene Brwf in Chinese cabbage (Brassica rapa L.)

Fine mapping and candidate gene analysis of the white flower gene Brwf in Chinese cabbage (Brassica rapa L.)

NingZhang, LinChen, Shuai Ma, RuofanWang, Qiong He, MinTian， Lugang Zhang

Scientific Reports

doi: 10.1038/s41598-020-63165-7

Abstract:Flower color can be applied to landscaping and identifcation of the purity of seeds in hybrid production. However, the molecular basis of white fower trait remains largely unknown in Brassica rapa. In this study, an F2 population was constructed from the cross between 15S1040 (white fower) and 92S105 (yellow fower) for fne mapping of white fower genes in B. rapa. Genetic analysis indicated that white fower trait is controlled by two recessive loci, Brwf1 and Brwf2. Using InDel and SNP markers, Brwf1 was mapped to a 49.6-kb region on chromosome A01 containing 9 annotated genes, and among them, Bra013602 encodes a plastid-lipid associated protein (PAP); Brwf2 was located in a 59.3-kb interval on chromosome A09 harboring 12 annotated genes, in which Bra031539 was annotated as a carotenoid isomerase gene (CRTISO). The amino acid sequences of BrPAP and BrCRTISO were compared between two yellow-fowered and three white-fowered lines and critical amino acid mutations of BrPAP and BrCRTISO were identifed between yellow-fowered and white-fowered lines. Therefore, Bra013602 and Bra031539 were predicted as potential candidates for white fower trait. Our results provide a foundation for further identifcation of Brwf and increase understanding of the molecular mechanisms underlying white fower formation in Chinese cabbage.