瓜叶菊谷胱甘肽转移酶基因GST的分离及表达分析

Isolation and Expression Analysis of GST Gene Encoding Glutathione S-transferase from Senecio cruentus

从瓜叶菊中克隆了10个谷胱甘肽转移酶（GST）基因，命名为ScGST1～10。序列相似性比较与基因表达分析结果显示，ScGST3可能是一个花青素苷转运相关的候选基因。对RT-PCR扩增的ScGST3序列分析发现，其包含一个639bp的开放阅读框，编码212个氨基酸残基，含有3个外显子和2个内含子，属于phi型GST；氨基酸序列比较分析表明，其与仙客来（Cyclamenpersicum）CkmGST3、香石竹（Dianthuscaryoph3，llus）DcGSTF2和矮牵牛（Petuniahybrida）PhAN9等花青素苷转运相关的GST具有较高的相似性；荧光定量PCR分析表明，该基因在含有花青素苷的组织中表达信号较强，在花序发育早期表达丰度最高，花序开放末期表达量下降。据此推测分离得到的ScGST3可能与瓜叶菊中花青素苷的转运与积累相关。

We cloned 10 glutathione transferase （GST） genes from Senecio cruentus and called after ScGST1- 10. ScGST3 was considered to be an alternative gene which related to the transfer of anthocyanin based on the similarity compare of sequence and analysis of gene expression. The amplified sequence of ScGST3 contains a 639 bp open reading frame, which encodes 212 amino acid residues. It also contains 3 exons and 2 introns and belongs to phi type GST. The compare analysis of amino acid sequence showed that the similarity between ScGST3 and other GSTs that related to the transfer of anthocyanin （ such as DcGSTF2 in Dianthus caryophyllus, CkmGST3 in Cyclamen persicum and PhAN9 in Petunia hybrida and so on） were higher. The analysis of fluorescent quantitation PCR showed that this gene had a higher expression in the tissues which contain anthocyanin. The expression reached the highest abundance and decreased at the early and final stages of inflorescence development, respectively. In conclusion, weinferred that ScGST3 might associate with the transfer and accumulation of anthocyanin in Senecio cruentus.