Preferential transport activity of Dk DTX5/MATE5 affects the formation of different astringency in persimmon  

作　　者：Ying Liu Xin Wu Chenfeng Sun Wenxing Chen Meng Zhang Niannian Liu Qinglin Zhang Liqing Xu Zhengrong Luo 

机构地区：[1]National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops,Huazhong Agricultural University,Wuhan 430070,China

出　　处：《Journal of Integrative Plant Biology》2023年第10期2304-2319,共16页植物学报（英文版）

基　　金：supported by the National Key R&D Program of China (2019YFD1000600)。

摘　　要：Proanthocyanidins(PAs) are specialized metabolites that infuence persimmon fruit quality.Normal astringent(A)-type and non-astringent(NA)-type mutants show significant variation in PA accumulation, but the infuencing mechanism remains unclear. In this study, among the six identified DTXs/MATEs proteins associated with PA accumulation, we observed that allelic variation and preferential transport by Dk DTX5/MATE5 induced variation in PA accumulation for A-type and NA-type fruit. The expression pattern of Dk DTX5/MATE5 was correlated with PA accumulation in NA-type fruit. Upregulation and downregulation of Dk DTX5/MATE5 promoted and inhibited PA accumulation, respectively, in the NA-type fruit. Interestingly, transporter assays of Xenopus laevis oocytes indicated that Dk DTX5/MATE5 preferentially transported the PA precursors catechin, epicatechin, and epicatechin gallate, resulting in their increased ratios relative to the total PAs, which was the main source of variation in PA accumulation between the A-type and NA-type. The allele lacking Ser-84 in Dk DTX5/MATE5 was identified as a dominantly expressed gene in the A-type and lost its transport function. Site-directed mutagenesis revealed that Dk DTX5/MATE5 binds to PA precursors via Ser-84. These findings clarify the association between the transporter function of Dk DTX5/MATE5 and PA variation, and can contribute to the breeding of new cultivars with improved fruit quality.

关 键 词：ASTRINGENCY DTX/MATE persimmon(Diospyros kaki Thunb.) proanthocyanidins(PAs) TONOPLAST TRANSMEMBRANE 

分 类 号：S665.2[农业科学—果树学]