转录因子LaMYB56调控乳白石蒜花色苷积累的研究OA

The new variety Lycoris albiflora'Astro Girl'with a unique color and a temporal variation pattern,has extremely high ornamental value and is an ideal material for studying the mechanism of plant color gradient.To explore flower color formation mechanism in L.albiflora,R2R3-MYBtranscription factor LaMYB56 gene associated with anthocyanin accumulation was cloned by RT-PCR.The regulation of anthocyanin accumulation was validated by molecular biology techniques.The results showed that the cDNA sequence of LaMYB56 with length of 1 031 bp and 723 bp ORF was obtained.LaMYB56 protein contains 2 conserved SANT domains at N-terminus.Phylogenetic analysis indicated that LaMYB56 was grouped with S20 subfamily in Arabidopsis thaliana.The expression level of LaMYB56 peaked on the first flowering day and gradually declined over time.The expression of LrF3'H,LrANS,LrGST genes were significantly decreased after silencing of LaMYB56 in the petals of L.radiata(P＜0.05).Overexpression of LaMYB56 in Arabidopsis significantly increased the expression levels of AtUFGT and AtF3'H(P＜0.05),leading to elevated anthocyanin content.The dual luciferase assay report and yeast one hybrid result indicated that LaMYB56 could bind to the promoter region of LaGST7 to regulate its expression and affect anthocyanin accumulation.The results demonstrated that LaMYB56 transcription factor was involved in the anthocyanins accumulation in L.albiflora.This study provides a theoretical found for the genetic improvement and molecular breeding of flower color in Lycoris genus and ornamental plants.