番茄与西瓜中番茄红素生物合成途径基因的比较分析

Comparison of Lycopene Biosynthetic Genes between Tomato and Watermelon

为了阐明番茄和西瓜中番茄红素生物合成途径的相关基因,借助比较基因组学,在全基因组水平上对两物种间该代谢途径进行了比较分析。在番茄中共鉴定了12个番茄红素生物合成途径基因,在西瓜中发现了14个相应的番茄红素生物合成途径基因,同时将所有基因定位到相应的染色体上。番茄和西瓜中直系同源番茄红素生物合成基因在核酸水平保持在54.8%-75.0%的一致性,而西瓜中相应的旁系同源基因在核酸水平上的一致性为70.5%-74.8%。番茄与西瓜中番茄红素直系同源基因间在基因结构上高度相似。且系统进化分析发现西瓜中番茄红素生物合成关键基因PSY（Cla005425）和LCYE（Cla016840）可能与胡萝卜中的直系同源基因拥有共同的祖先。

In order to elucidate the genes related to the lycopene biosynthetic pathway in tomato and watermelon,we conducted comparative genomic analyses of lycopene biosynthetic pathway in these two crop species at a genome- wide level. We identified 12 lycopene biosynthetic genes in tomato,and found 14 relevant lycopene biosynthetic genes in watermelon. All these genes were successfully mapped on the related chromosomes. The orthologous lycopene biosynthetic genes between tomato and watermelon shared54. 8% - 75. 0% nucleotide sequence identity,while the relevant paralogous lycopene biosynthetic genes in watermelon shared70. 5% - 74. 8% nucleotide sequence identity. The structure of lycopene biosynthetic genes in tomato was highly similar to that of their orthologous genes in watermelon. Moreover,the phylogenetic trees indicated that the lycopene biosynthetic genes PSY（ Cla005425） and LCYE（ Cla016840） in watermelon maybe shared the same ancestor with their orthologous genes in carrot.