‘月月粉’和野蔷薇花青素合成酶基因的鉴定与表达分析

植物花青素是一种天然的黄酮类水溶性植物色素,对于植物的花和果实的花色决定具有重要作用,花青素在植物体内的生物合成途径研究相对较清楚。但在蔷薇属植物中花青素合成酶基因的功能分析相对较少,通过序列比对和进化树分析鉴定‘月月粉’(Rosa chinensis‘Old Blush’,用OB表示)和野蔷薇(Rosa multiflora)中花青素合成酶基因各14个。通过序列比较发现野蔷薇和OB中对应的同源基因序列相似性很高,表明这些基因的保守性很强,但表达谱分析显示这些基因在两个物种中的差异较大,暗示其调控序列可能变异程度较大。通过检测一个野蔷薇自然突变单株中红花和白花中的花青素合成酶基因的表达,推测有部分花青素合成酶基因可能在花青素合成反馈调节中具有重要作用。通过分析启动子序列中顺式作用元件推测OB中花青素合成酶可能受蔗糖和不同激素的调控。本研究可为揭示蔷薇属植物花青素合成调控的分子机制提供依据。

Identification and Expression Analysis of Anthocyanin Biosynthesis Genes in Rosa chinensis and Rosa multiflora

Plant anthocyanin is a water-soluble flavonoid pigment,which plays an important role in determining color of flower and fruit.Anthocyanin biosynthesis pathway has been clearly demonstrated in plant.However,function of anthocyanin biosynthesis genes in rose has hardly been revealed.In this study,14 anthocyanin biosynthesis genes were identified in Rosa chinensis’Old Blush’(OB)and Rosa multiflora by sequence alignment and phylogenetic analysis.High similarity of homologous genes in Rosa chinensis and Rosa multiflora was found by comparing the protein sequences,suggesting strong conservation of these genes in rose.Expression analysis indicated that expression profile of homologous genes was different in two species,implying that regulatory sequences of these genes may vary to a larger extent.It was speculated that some of these genes may be involved in retro-regulation of anthocyanin biosynthesis when we tested expression of these genes in red and white flower in the same plant of Rosa multiflora.These genes were also regulated by sucrose and hormones as many cis-elements were found in their promoter region.This study lay foundation for uncovering molecular mechanism of anthocyanin biosynthesis regulation.