ABA信号通路对葡萄果皮花青苷生物合成的调控机制研究

Regulation Mechanism of ABA Pathway Genes on Anthocyanin Biosynthesis in Grape Skins

以‘红巴拉多’葡萄为试验材料,在转色前期(约花后6周)用300 mg/L的ABA对果穗进行处理,以清水处理为对照;测定不同发育时期葡萄果实的单果重、可滴定酸、可溶性固性物等生理指标,同时测定果皮中总花青苷及ABA含量;检测不同发育时期果皮中ABA信号通路和花青苷生物合成相关基因表达量,克隆6个与花青苷生物合成相关基因的启动子,并预测启动子中的顺式作用元件,在转录调控水平上探讨ABA信号通路对葡萄果皮花青苷生物合成的调控作用。结果表明:(1)ABA处理的葡萄果实可溶性固形物含量明显提高、可滴定酸含量下降。(2)ABA处理显著提高了‘红巴拉多’葡萄果皮的着色水平以及总花青苷和ABA含量。(3)ABA处理后,9个ABA信号通路基因以及6个花青苷生物合成相关基因表达水平明显提高。(4)6个花青苷生物合成相关基因的启动子序列中均含有多个与ABA响应相关的ABRE作用元件。研究发现,9个ABA信号通路基因可能在葡萄果皮着色中发挥着重要作用,其中2个VvABFs转录因子可能直接作用于含有ABRE元件的花青苷生物合成相关基因的启动子序列,推测可通过调控这些基因的转录水平来调控葡萄果皮花青苷的积累。

Present study use‘Benibalado’as the experimental material.In the early stage of véraison,grape clusters were treated with 300 mg/L ABA,water treated as control.The weight,titratable acid and total soluble solids of grape berries at different development stages were determined.Meanwhile,we detected the concentrations of total anthocyanins and endogenous hormone ABA in grape skins.The expression of ABA signaling pathway and anthocyanin biosynthesis related genes in skins of different development stages were observed by qRT-PCR.Promoters of 6 anthocyanin biosynthesis related genes were cloned by PCR,the cis-acting elements in these promoters were predicted to exploring the mechanism of ABA promoted grape skin coloring and anthocyanin accumulation of‘Benibalado’grape at transcriptional regulation level.The results showed that:(1)ABA treatment significantly increased the total soluble solid while decreased titratable acid of‘Benibalado’grape.(2)ABA treatment significantly increased the anthocyanin content and endogenous ABA content in the skin of‘Benibalado’berries.(3)After ABA treatment,the expression levels of 9 ABA signaling pathway genes and 6 anthocyanin biosynthesis related genes of‘Benibalado’grape skins were significantly increased.(4)The results of cis-acting element analyzing showed that the promoter sequences of above six anthocyanin biosynthesis related genes contained several ABRE motif which were reported related to ABA signal response.In summary,the results suggested that 9 ABA signaling pathway genes may play important roles in grape skins coloring,two of them(VvABFs)may directly works with the promoter sequence of anthocyanin biosynthesis related genes,which are abundant of ABRE elements to positive regulate the transcription level of downstream genes and eventually modulate the skins coloring and anthocyanin accumulation of grape.