The regulation of ABA-induced anthocyanin accumulation in grape berry
Abstract
Color is a key quality trait for grape berry and the producing wines. Berry color of red genotypes is mainly determined by the quantity and composition of anthocyanins accumulated in the skin and/or pulp. Both genetic and environmental factors could influence the quantity and composition of anthocyanins, while the underlying mechanisms are not fully clear. To explore the mechanisms underlying the diversity of anthocyanin accumulation in grape berry, we compared two grapevine genotypes showing distinct sensitivities to ABA-induced anthocyanin biosynthesis, where one genotype showed minor responses to exogenous ABA application while the other showed significant increase in anthocyanins after exogenous ABA application. Transcriptome and metabolome were conducted and their analysis pointed out that the cis-element of MYBA1 might be responsible for the observed phenotypes. The promoters of MYBA1 were then cloned from both genotypes and several differences in their sequences were observed, but without any mutations in the ABRE elements. Dual-luciferase assay was applied to test the promoter activity and their responses to ABA, with a series of fragmented promoters of MYBA1 from both genotypes. The mutations in a portion of promoter not containing any ABREs were identified as the core for determining the sensitivity of ABA-induced anthocyanin accumulation. These results show the importance of sequence context on the function of cis-element and provide novel insights into the understanding of the mechanisms underlying the diversity of anthocyanin accumulation in grape berry.
DOI:
Publication date: June 13, 2024
Issue: Open GPB 2024
Type: Article
Authors
1 State Key Laboratory of Plant Diversity and Specialty Crops, Beijing Key Laboratory of Grape Sciences and Enology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
2 China National Botanical Garden, Beijing 100093, China
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Keywords
color, cis-regulation, sequence context, anthocyanin diversity, metabolism