A STAY-GREEN protein SlSGR1 regulates lycopene and β-carotene accumulation by interacting directly with SlPSY1 during ripening processes in tomato
A STAY-GREEN protein SlSGR1 regulates lycopene and β-carotene accumulation by interacting directly with SlPSY1 during ripening processes in tomato
复制标题
STAY-GREEN 蛋白 SlSGR1 在番茄成熟过程中通过与 SlPSY1 直接相互作用来调节番茄红素和 β-胡萝卜素的积累
DOI：
10.1111/nph.12175
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发表时间：
2013-04-01
期刊：
影响因子：
9.4
通讯作者：
Ye, Zhibiao
中科院分区：
文献类型：
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作者：
Luo, Zhidan;Zhang, Junhong;Ye, Zhibiao
作为人类饮食中番茄红素的主要来源，肉质水果在成熟过程中通过自发和叶绿素代谢合成这种化合物。SlSGR1编码一种STAY-GREEN蛋白，该蛋白在番茄叶片和果实的叶绿素降解调控中起关键作用。我们报道SlSGR1可以通过与类胡萝卜素合成酶SlPSY1的直接作用调控番茄红素的积累，并抑制其活性。这种与SlSGR1的相互作用介导了番茄果实成熟过程中番茄红素的积累。我们在生产番茄红素的细菌中证实了这种抑制活性，其中SlSGR1的引入显著减少了番茄红素的生物合成。SlSGR1基因在转基因番茄果实中的抑制作用改变了植物烯和番茄红素的积累模式，同时提高了果实成熟早期SlPSY1 mRNA的积累和质体转化，导致红熟果实中番茄红素和-胡萝卜素的含量分别增加了4倍和9倍。SlSGR1通过改变乙烯受体基因和乙烯诱导基因的表达影响乙烯信号转导。slsgr1抑制的番茄水果货架期显著延长。研究结果表明，SlSGR1在番茄颜色形成和果实成熟调控中起着关键的调节作用，并进一步表明SlSGR1的活性是通过与PSY1的直接相互作用介导的。
As a primary source of lycopene in the human diet, fleshy fruits synthesize this compound both denovo and via chlorophyll metabolism during ripening. SlSGR1 encodes a STAY-GREEN protein that plays a critical role in the regulation of chlorophyll degradation in tomato leaves and fruits. We report that SlSGR1 can regulate tomato (Solanum lycopersicum) lycopene accumulation through direct interaction with a key carotenoid synthetic enzyme SlPSY1, and can inhibit its activity. This interaction with SlSGR1 mediates lycopene accumulation during tomato fruit maturation. We confirmed this inhibitory activity in bacteria engineered to produce lycopene, where the introduction of SlSGR1 reduced dramatically lycopene biosynthesis. The repression of SlSGR1 in transgenic tomato fruits resulted in altered accumulation patterns of phytoene and lycopene, whilst simultaneously elevating SlPSY1 mRNA accumulation and plastid conversion at the early stages of fruit ripening, resulting in increased lycopene and -carotene (four- and nine-fold, respectively) in red ripe fruits. SlSGR1 influences ethylene signal transduction via the altered expression of ethylene receptor genes and ethylene-induced genes. Fruit shelf-life is extended significantly in SlSGR1-repressed tomatoes. Our results indicate that SlSGR1 plays a pivotal regulatory role in color formation and fruit ripening regulation in tomato, and further suggest that SlSGR1 activity is mediated through direct interaction with PSY1.