【摘要】 为了解MYBF基因在葡萄黄酮醇生物合成途径中的作用，首先对VvMYBF2进行生物信息学和组织表达特异性分析，然后以红色品种品丽珠、赤霞珠和白色品种霞多丽3个酿酒葡萄品种为材料，利用qRT-PCR分析VvMYBF2基因在不同组织中的表达量，同时测定果实中黄酮醇等次生代谢物含量。结果显示，VvMYBF2编码氨基酸383个，分子质量为42.52 ku，为不稳定的酸性亲水性蛋白，无跨膜转运信号，非膜上受体，无信号肽存在，VvMYBF2与VvMYBF1的外显子和Motif数量相同但分布不同；组织特异性分析表明，在果皮、芽、叶以及卷须中表达量相对较高。qRT-PCR结果显示，VvMYBF2基因在果皮中表达量最高，果肉和叶次之，尤以白色品种霞多丽果皮中表达量最高；次生代谢物含量分析发现，3个品种的果皮均以黄烷醇含量最高，果肉中总酚含量最高；值得注意的是，果皮中红色品种赤霞珠各次生代谢物含量均显著高于白色品种，果肉中表现无规律，这与VvMYBF2的表达量成反比，说明VvMYBF2可能参与调控葡萄果皮颜色；而同为红色品种的品丽珠果皮中各次生代谢物含量均显著低于赤霞珠，这与其VvMYBF2的表达量一致，说明VvMYBF2参与调控葡萄果皮中次生代谢物合成，尤其是总酚和黄烷醇的合成。综上说明，VvMYBF2基因在果皮黄酮醇等次生代谢物合成及果皮颜色形成中均起着重要作用。更多还原

【Abstract】 To understand the role of MYBF genes in the biosynthesis pathway of grape flavonols, in this study, analysis of bioinformatics and tissue expression specificity of VvMYBF2 was firstly conducted, then,using three varities of grapes making wine including red varieties Cabernet Franc and Cabernet Sauvignon, and the white variety Chardonnay as materials, the expression levels of VvMYBF2 in different tissue were measured by qRT-PCR, and the contents of secondary metabolites such as flavonols were measured at the same time. The results showed that VvMYBF2 encoded 383 amino acids with a relative molecular weight of 42.52 ku, which was an unstable acidic hydrophilic protein with no transmembrane transport signal, no membrane receptor or no signal peptide. The exons and motif of VvMYBF1 and VvMYBF2 were the same in number but different in distribution. Tissue specificity analysis showed that the expression levels in pericarp, bud, leaf and tendril were relatively high. The results of qRT-PCR showed that the VvMYBF2 gene had the highest expression in pericarp, followed by the flesh and leaves, especially in the pericarp of the white variety Chardonnay. The content analysis of secondary metabolite showed that flavanol content was the highest in pericarp and total phenol content was the highest in flesh of three varieties. In particular, the contents of secondary metabolites in pericarp of the red variety Cabernet Sauvignon were significantly higher than those of the white variety, while the contents in flesh were not regular, which was in inverse proportion to the expression level of VvMYBF2 indicating that VvMYBF2 was probably involved in regulating grape pericarp color. In two red varieties, the contents of secondary metabolites in the pericarp of Cabernet Franc were significantly lower than that of Cabernet Sauvignon,which was consistent with the expression level of VvMYBF2, indicating that VvMYBF2 was involved in regulating the synthesis of secondary metabolites in grape peels, especially synthesis of total phenolics and flavanols. In conclusion, the VvMYBF2 gene played an important role in synthesis of secondary metabolites such as flavonols and color formation in grape pericarp.更多还原