A Ma10 gene encoding P-type ATPase is involved in fruit organic acid accumulation in apple

First author: Baiquan Ma; Affiliations: Wuhan Botanical Garden, Chinese Academy of Sciences (中科院武汉植物园): Wuhan, China

Corresponding author: Yuepeng Han (韩月彭)

Acidity (酸度) is one of the main determinants of fruit organoleptic quality (感官品质). Here, comparative transcriptome analysis was conducted between two cultivars that showed a significant difference in fruit acidity, but contained homozygous non‐functional alleles at the major gene Ma1 locus controlling apple fruit acidity. A candidate gene for fruit acidity, designated M10, was identified. The M10 gene encodes a P-type proton pump (P型质子泵), P3A-ATPase, which facilitates malate (苹果酸盐) uptake into the vacuole (液泡). The Ma10 gene is significantly associated with fruit malate content, accounting for ~7.5% of the observed phenotypic variation in apple germplasm (种质). Subcellular localization assay showed that the Ma10 is targeted to the tonoplast (液泡膜). Overexpression of the Ma10 gene can complement the defect in proton transport of the mutant YAK2 yeast strain and enhance accumulation of malic acid (苹果酸) in apple callus. Moreover, its ectopic expression in tomato induces a decrease in fruit pH. These results suggest that the Ma10 gene has the capacity for proton pumping and plays an important role in fruit vacuolar acidification (酸化) in apple. Our study provides useful knowledge towards comprehensive understanding of the complex mechanism regulating apple fruit acidity.

酸度是水果感官品质的一个主要决定因素。本文对水果酸度上呈显著差异的两个栽培种苹果进行了比较转录组学研究，这两个栽培种在控制苹果果实酸度主效基因Ma1位点上表现为纯合非功能性等位基因。作者鉴定到了一个控制水果酸度候选基因，命名为M10。M10基因编码了一个P型质子泵P3A‐ATPase，该酶促进液泡吸收苹果酸盐。Ma10基因与水果的酸度显著相关，在不同苹果种质之间的表型变异约在7.5%。亚细胞定位试验显示Ma10靶向于液泡膜。过表达Ma10基因能够互补YAK2酵母菌株质子转运突变体的表型，并且增强苹果愈伤的苹果酸积累。此外，在番茄中的异源表达能够诱导水果PH值的降低。本文的研究结果显示Ma10基因作用于质子泵，并在苹果果实的液泡酸化中发挥重要作用。作者的研究为进一步理解苹果果实酸度的调控机制提供了新的见解。

通讯：韩月彭（http://sourcedb.wbg.cas.cn/zw/rck/200907/t20090720_2708436.html）

个人简介：1989-1993年，江苏农学院，本科；1998-2001年，扬州大学农学院，作物遗传育种，硕士；2001-2004年，扬州大学农学院，作物遗传育种，博士；2004-2009年，美国伊利诺大学香槟分校，苹果基因组研究，博士后。

研究方向：果树果实品质与代谢的分子遗传学，以苹果、桃为材料，研究糖、酸、色泽等代谢产物的合成途径与调控机理，着重于阐明风味和色泽性状形成的分子机理，并致力于果树的分子改良，创制优质新材料。

doi: https://doi.org/10.1111/pbi.13007

Journal: Plant Biotechnology Journal

First Published: 05 September, 2018

（P.S. 原文下载：链接:https://pan.baidu.com/s/1qFiSsqwlF_7JjmGMbedfhQ  密码:dmu6）