‘烟73’葡萄果皮花色苷合成、修饰与转运相关基因的表达

Expression of Genes Related to Anthocyanin Synthesis,Modification and Transport in‘Yan 73’Grape Skin

花色苷在内质网中合成,而在液泡中发挥生理学功能,因此花色苷液泡转运过程非常关键。研究葡萄果皮中花色苷合成,修饰与转运基因的表达模式,有助于解析花色苷从合成到转运的完整通路。以宁夏青铜峡地区红色酿酒葡萄品种‘烟73’为材料,在果实成熟过程中测定可溶性固形物、可滴定酸含量pH及果皮总酚、单宁、花色苷含量,利用实时荧光定量PCR检测葡萄果皮中花色苷合成,修饰与转运相关基因表达水平。结果表明,成熟期‘烟73’可溶性固形物、可滴定酸和pH分别为(23.50±0.30)%、(3.22±0.03)g·L-1和3.59±0.10;果皮单宁、总酚及花色苷含量分别为(22.32±1.15)mg·g^-1(果皮干质量)、(62.50±1.23)mg·g^-1和(52.49±1.10)mg·g^-1。定量PCR结果显示,在果实成熟过程中,‘烟73’葡萄果皮VviUFGT、VviGST1、VviGST2、VviGST3及VviGST4基因表达趋势基本相同,呈先上升后下降趋势,且在花后10周表达量达最高值;VviOMT基因表达总体呈下降趋势,花后8周和10周同其他时期相比存在显著性差异;AM1与AM3基因表达呈“M”型变化趋势,花后10周与14周表达较高。相关性分析显示,‘烟73’中VviGST1、VviGST2、VviGST3以及VviGST4基因的表达趋势与花色苷积累量显著正相关,VviGST1与VviOMT显著正相关。综上所述,‘烟73’葡萄果实理化及多酚成熟度较好,4个GST家族基因均参与了花色苷的液泡转运,其中VviGST1可能参与了‘烟73’果皮中甲基化花色苷的转运。

The vacuolar transport of anthocyanins is critical because the biosynthesis of anthocyanins occurs in the endoplasmic reticulum and exerts its functions in vacuoles.The expression level of gene related to anthocyanin synthesis,modification and transport will be helpful to analyze the vacuolar transport of anthocyanins.Using red grape variety‘Yan 73’collected from Qingtongxia in Ningxia province as material,the total soluble solids content(TSS),titratable acid content,pH,total phenolic compounds,tannin,total anthocyanin were measured.Real-time quantitative PCR was used to detect the expression level of anthocyanin synthesis and genes related to transport in skin.The results showed that the soluble solids content of‘Yan 73’in mature period was(23.50±0.30)%,titratable acid content was(3.22±0.10)g·L-1 and pH was 3.59±0.10.Tannin,total phenolic compounds and total anthocyanin contents in grape skin were(22.32±1.15)mg·g^-1(skin dry mass),(62.50±1.23)mg·g^-1 and(52.49±1.10)mg·g^-1.Quantitative PCR results showed that the trends of VviUFGT,VviGST1,VviGST2,VviGST3 and VviGST4 were basically same in the‘Yan 73’grape skin,both of which increased first and then decreased,and reached the highest value at 10 weeks after flowering.VviOMT showed a general downward trend compared with other periods,there were significant difference between 8 weeks and 10 weeks after flowering.AM1 and AM3 showed change trend of“M”-like and the expression levels were higher at 10 and 14 weeks after flowering.Correlation analysis showed that VviGST1,VviGST2,VviGST3 and VviGST4 were significantly associated with anthocyanin accumulation in‘Yan 73’,and VviGST1 was significantly associated with VviOMT.In conclusion,the maturity of‘Yan 73’is good enough for the experiment,4 GST family genes are involved in the vacuolar transport of anthocyanins,and VviGST1 is involved in the transport of methylated anthocyanins in the‘Yan 73’skin.