Role for the banana AGAMOUS-like gene MaMADS7 in regulation of fruit ripening and quality
Role for the banana AGAMOUS-like gene MaMADS7 in regulation of fruit ripening and quality
复制标题
香蕉 AGAMOUS 样基因 MaMADS7 在果实成熟和品质调控中的作用
DOI：
10.1111/ppl.12348
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发表时间：
2015-11-01
影响因子：
6.4
通讯作者：
Jin, Zhiqiang
中科院分区：
文献类型：
--
作者：
Liu, Juhua;Liu, Lin;Jin, Zhiqiang
MADS-box转录因子在器官发育中起重要作用。在植物中，大多数关于MADS-box基因的研究主要集中在花的发育上，很少涉及果实的发育和成熟。以香蕉抑制减法杂交（SSH） cDNA文库中的MADS-box片段为基础，利用cDNA末端快速扩增技术（RACE）从香蕉果实中分离到一个新的MADS-box基因MaMADS7。MaMADS7是一种类似agamous的MADS-box基因，在卵巢、果实和烟草中优先表达，其蛋白产物定位于细胞核。本研究发现外源乙烯可诱导MaMADS7表达。MaMADS7在番茄中的异位表达导致了广泛的成熟表型。在MaMADS7转基因番茄果实中，ACO1、ACS2、E4、E8、PG、CNR和PSY1等7个成熟品质相关基因的表达量显著增加，而ag样MADS-box基因TAGL1的表达量受到抑制。与对照相比，转化番茄果实中-胡萝卜素、番茄红素、抗坏血酸和有机酸含量均有所增加，葡萄糖和果糖含量略有下降。MaMADS7与香蕉1-氨基环丙烷-1-羧酸（ACC）氧化酶基因1 （MaACO1）和番茄植物烯合成酶基因（LePSY1）启动子相互作用。结果表明，MaMADS7在启动内源乙烯生物合成和果实成熟过程中起重要作用。
MADS-box transcription factors play important roles in organ development. In plants, most studies on MADS-box genes have mainly focused on flower development and only a few concerned fruit development and ripening. A new MADS-box gene named MaMADS7 was isolated from banana fruit by rapid amplification of cDNA ends (RACE) based on a MADS-box fragment obtained from a banana suppression subtractive hybridization (SSH) cDNA library. MaMADS7 is an AGAMOUS-like MADS-box gene that is preferentially expressed in the ovaries and fruits and in tobacco its protein product localizes to the nucleus. This study found that MaMADS7 expression can be induced by exogenous ethylene. Ectopic expression of MaMADS7 in tomato resulted in broad ripening phenotypes. The expression levels of seven ripening and quality-related genes, ACO1, ACS2, E4, E8, PG, CNR and PSY1 in MaMADS7 transgenic tomato fruits were greatly increased while the expression of the AG-like MADS-box gene TAGL1 was suppressed. Compared with the control, the contents of -carotene, lycopene, ascorbic acid and organic acid in transformed tomato fruits were increased, while the contents of glucose and fructose were slightly decreased. MaMADS7 interacted with banana 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene 1 (MaACO1) and tomato phytoene synthase gene (LePSY1) promoters. Our results indicated that MaMADS7 plays an important role in initiating endogenous ethylene biosynthesis and fruit ripening.