葡萄果皮类黄酮含量的变化及其相关基因表达

Change of flavonoid content and relevant genes expression in grape peel during berries development

检测‘夏黑’葡萄果实生长发育过程中果皮内4种类黄酮化合物(黄酮醇、黄烷醇、原花色素和花色素苷)及总类黄酮的含量,分析相关基因的表达模式。结果表明:‘夏黑’葡萄果皮黄酮醇含量在花后21~31d达峰值,为0.185~0.195 mg/g,花后52 d降至最低,为0.009 mg/g,随后再次缓慢升高直至果实成熟;黄烷醇和原花色素含量的变化相似,均是花后21~42 d迅速增加至峰值,分别达到3.238 mg/g和8.604 mg/g,之后随果实成熟逐渐下降,至花后80d时降至最低值;花色素苷含量则至花后42d后才能检测到,并随果实生长开始增加,直至成熟时达到峰值9.664 mg/g;类黄酮含量花后21~31 d逐步下降,但花后42 d时迅速升高达到峰值,为18.723 mg/g,然后随果实生长含量逐渐降低;黄酮醇合酶基因(FLS)在转色前表达水平低,之后显著上升,临近成熟时再次下降,与黄酮醇含量变化不一致;无色花色素双加氧酶基因(LDOX)和UDP–葡萄糖–类黄酮–3–O–糖苷转移酶基因(UFGT)的表达水平从转色期前开始升高,直到果实成熟达到最高值,与花色素含量变化一致;无色花色素还原酶基因(LAR)和花色素还原酶基因(ANR)的表达水平随果实成熟逐渐降低,与黄烷醇和原花色素的含量变化趋势一致。

Contents of four main kinds of flavonoids(flavonols, flavanols, proanthocyanidins and anthocyanins) and total flavonoids were detected in ‘Summer Black’ grape peel during the berries development. Expression patterns of genes involved in the flavonoids biosynthesis were also tested correspondingly. The highest flavonols content was detected in 21 days after full bloom(DAFB) and 31 DAFB(0.195 mg/g and 0.185 mg/g, respectively), then decreased markedly with berries growth and reached the lowest level(0.009 mg/g) in 52 DAFB. This was followed by a continuous rise until berries mature. Flavanols and proanthocyanidins have similar change patterns. Both of their content increase rapidly from 21 to 42 DAFB, reaching the highest level which were 3.238 mg/g and 8.604 mg/g respectively, then followed by a clear decline until the lowest level in 80 DAFB. Anthocyanins content was detected till 42 DAFB, then increased rapidly with berries development and reached the highest level(9.664 mg/g) at mature. Flavonoids content descended from 21 to 31 DAFB, then increased rapidly and reach highest level(18.723 mg/g) in 42 DAFB, followed a decline until berries mature. The relative expression level of flavonol synthase(FLS) was lower before veraison, then increased obviously and decreased again near maturity, which was not consistent with the changes of flavonols contents. Relative expression level of leucoanthocyanidin dioxygenase(LDOX) and UDP-glucose: flavonoid-3-O-glucosyltransferase(UFGT) increased gradually from veraison and reached the highest in maturity and were consistent with the content changes of anthocyanins. Relative expression level of leucoanthocyanidin reductase(LAR) and anthocyanidin reductase(ANR) decline continuously during the development of berries, which were consistent with the contents changes of flavanols and proanthocyanidins.