摘 要 :查尔酮合成酶(Chalcone Synthase,CHS)是植物体类黄酮类化合物合成的第一个关键酶,限速酶,它催化丙二酰-CoA 和对香豆酸-CoA 合成柚皮素查尔酮。二苯乙烯合成酶(Stilbene synthase,STS)是芪类化合物合成路径的关键酶,和查尔酮合成酶有共同的作用底物,二者之间具有很高的相似度。为更好的了解葡萄中CHS和STS基因的种类和数量,本文采用生物信息学方法检索获得葡萄(Vitisvinifera L.)基因组数据库中的CHS和STS基因,通过分析其染色体定位、系统进化和保守基序,发现葡萄基因组可能含有33个STS基因,9个CHS基因,这些基因集中分布在6条葡萄染色体上,部分家族基因在染色体上形成基因簇。葡萄CHS和STS基因家族蛋白长度、基因结构和蛋白基序非常保守,具有很近的进化关系。葡萄芯片数据结果表明,葡萄CHS和STS基因在葡萄果实不同发育时期的果皮和果肉中均有表达,尤其葡萄CHS Groups Ⅲ亚家族基因在葡萄果皮中大量表达。葡萄STS基因家族在果实中的表达量较低,部分探针在葡萄果实成熟期的果皮中表达量急剧增加。本研究结果为葡萄CHS和STS基因在果实发育过程中的功能研究提供参考。
Abstract:Chalcone synthase (CHS) provides the first committed step of flavonoid biosynthesis by condensing one molecule of p-coumaroyl-CoA with three molecules of malonyl-CoA to produce tetrahydroxychalcone. Chalcone synthases are closely related to stilbene synthases (STS), the key enzymes of the stilbenes pathway, as illustrated by the fact that both enzymes share the same substrates. To better understand the variety and quantity of CHS and STS genes in grape, we used bioinformatics methods to screen the auxin-response genes from the grape genome database, and analyzed their chromosomal location, phylogenetic analysis and conserved motif. Our results showed that 33 STS and 9 CHS genes were identified, and there genes were concentrated on 6 chromosomes, and some of them formed distinct tandem duplicate gene clusters. Grape CHS and STS genes had conserved sequence length, gene structure, protein motif, and closely evolutionary relationships. The available grape microarray databases showed that all of CHS and STS genes were expressed in grape pulp and skin, especially CHS Groups Ⅲ genes were highly expressed in grape skin. STS genes were poorly expressed in grape fruit, but some of them were highly expressed in the skin of mature fruits. This paper provides a resource for functional studies of CHS and STS genes in grape fruit development.