山药花青素合成关键酶基因的解析

Analysis of Genes Involved in Key Enzymes of Anthocyanin Biosynthesis in Chinese Yam( Dioscorea alata)

测定了紫山药和白山药叶、茎、块茎中的花青素含量、积累量和积累速率,以及花青素合成酶基因PAL、F3H、DFR、ANS和UFGT的实时表达。结果表明:除了DFR基因外其他基因在山药幼嫩组织中的表达水平更高;所有基因在紫山药块茎中的表达水平较高;ANS和UFGT在紫山药中高度表达,而在白山药中低表达或不表达;块茎中花青素的动态积累量呈一个典型的双"S"曲线;PAL和F3H基因只在花青素积累速率最快之前的块茎膨大初期高度表达,而DFR、ANS和UFGT表达水平的两个高峰期与花青素积累速率的两个高峰期符合。推测控制紫山药颜色的关键酶基因可能是ANS和UFGT或两者之一。

The author measured the content,accumulation amount and accumulation rate of anthocyanin in the leaves,stems and root tubers of purple and white Chinese yam（ Dioscorea alata L.）,as well as the real-time expression of anthocyanin biosynthetic enzyme genes PAL,F3 H,DFR,ANS and UFGT. The results showed that： the expression levels of all genes（ except for DFR） in the tender tissues of Chinese yam were higher; the expression levels of all genes in the root tubers of purple Chinese yam were higher; the genes ANS and UFGT expressed highly in purple Chinese yam,while they expressed lowly or did not express in white Chinese yam; the dynamic accumulation amount of anthocyanin in root tubers revealed a typical double-S curve; the genes PAL and F3 H expressed highly only at the initial stage of root tuber expansion before the highest accumulation rate of anthocyanin;the expression levels of genes DFR,ANS and UFGT exhibited two peak periods,which accorded with the two peak periods of anthocyanin accumulation rate. It was speculated that the key enzymatic genes controlling the color of purple Chinese yam maybe were ANS and UFGT or one of them.