FaSPS1基因对草莓果实成熟调控的分子机理

Molecular Mechanism of FaSPS1 Gene Regulation in Strawberry Fruit Development

该研究以草莓品种‘红颜’(Fragaria×ananassa‘Benihoppe’)为试材,分析了草莓果实发育不同阶段蔗糖磷酸合成酶基因(FaSPS1)的表达量变化,采用PCR方法克隆FaSPS1基因,构建带有报告基因的e-GFP植物表达载体,通过瞬时转基因方法转化草莓果实,采用观察绿色荧光和检测目的基因表达量的方法鉴定转基因植物,并分析FaSPS1基因超表达和反义表达后草莓果实的成熟发育以及与成熟相关的基因表达量变化,探究FaSPS1基因在果实成熟发育中的特殊作用,为深入了解草莓果实发育和成熟调控的分子机理提供思路。结果显示:(1)成功克隆得到FaSPS1基因(GenBank登录号AB267868.1);成功构建带有报告基因e-GFP的FaSPS1基因超表达载体和反义基因表达载体,通过瞬时转基因方法转化并经荧光和目的基因表达量检测的方法鉴定获得转FaSPS1基因草莓植株。(2)与空载对照和非转基因果实相比,FaSPS1基因过表达可促进草莓果实成熟,能够使草莓果实成熟期提前,且果实中蔗糖果糖含量升高;但反义表达后会抑制草莓果实成熟,果实中苹果酸含量升高。(3)基因超表达或者反义表达后,草莓果实成熟相关基因的表达量受到不同程度调控,其中糖代谢基因FaSPS2/3、FaSUT1,果实成软化基因FaEXP1、FaEXP3、FaXYL1以及激素代谢基因FaJAZ1、FaJAZ2、FaJAZ8、FaOPR3、FaPYL1、FaPYL8、FaPYL9、FaNCED1表达量变化最明显。研究推测,FaSPS1基因可能通过影响草莓果实中和成熟相关的糖代谢基因、果实软化基因以及激素代谢基因来调控草莓果实成熟。

This study used strawberry variety ‘Benihoppe’ as test material. The FaSPS 1 gene expression in different stages of strawberry fruit development was analyzed. The FaSPS 1 gene was cloned by PCR and the plant expression vector with reporter e-GFP gene was constructed. The strawberry fruit was transformed by transient transgene method. The aim of this study was to identify the transgenic plants by detecting the expression of FaSPS 1 gene and observe green fluorescence. The changes of the expression of FaSPS 1 gene during the ripening and development of strawberry fruits were analyzed after the overexpression and antisense expression of FaSPS 1 gene. The special role of FaSPS 1 gene in the ripening and development of strawberry fruits was explored to provide ideas for further understanding the molecular mechanism of strawberry fruit development and ripening regulation. The results showed that:(1) FaSPS 1 gene (GenBank number AB267868.1) was successfully cloned;FaSPS 1 gene overexpression vector and antisense gene expression vector with reporter gene e-GFP were successfully constructed, and the transgenic strawberry plants were identified by transient transgene transformation and fluorescence and target gene expression detection.(2) Overexpression of FaSPS 1 gene can promote the ripening of strawberry fruit, advance the ripening period of strawberry fruit, and increase the sucrose and fructose contents in the fruit, but antisense expression can inhibit the ripening of strawberry fruit and increase the malic acid content in the fruit.(3) After gene overexpression or antisense expression, the expression of ripening-related genes in strawberry fruits were regulated to varying degrees. Among them, sugar metabolism genes FaSPS 2/3, FaSUT 1, fruit softening genes FaEXP 1, FaEXP 3, FaXYL 1 and hormone metabolism genes FaJAZ 1, FaJAZ 2, FaJAZ 8, FaOPR 3, FaPYL 1, FaPYL 8, FaPYL 9 and FaNCED 1 showed the most significant changes. It is speculated that FaSPS 1 gene may regulate strawberry fruit ripening by affecting sugar metabolism genes, fruit softening genes and hormone metabolism genes related to fruit ripening.