决明查尔酮合成酶全长基因序列的克隆与分析

Cloning and Sequence Analysis of Chalone Synthase Gene from Cassia tora

从决明(Cassia tora)的新鲜子叶中提取基因组DNA作为模板,利用一对特异引物进行PCR扩增,然后克隆测序得到决明查尔酮合成酶(CHS)的基因全长。测序结果表明,决明CHS基因全长为1 766 bp,含有2个外显子和1个内含子。将其提交GenBank,登录号为(JX676773)。决明CHS基因的内含子位于188-765 bp之间,长度为578 bp,内含子的剪切符合GU-AG规律,含有多个酶切位点和顺式调控元件,可能与决明CHS基因的表达调控有关。CHS基因内含子具有多态性,可能是由不同植物存在多样性的生活史与生活环境导致的。决明CHS基因外显子2较为保守,编码几乎所有CHS的功能位点。构建外显子2编码氨基酸序列的NJ系统发育进化树,能够正确反映不同植物的亲缘关系,可用于不同植物的遗传分化和分子进化研究。

The chalcone synthase（CHS）gene was cloned from the fresh cotyledons of Cassia tora,using genomic DNA as a template and a pair of specific primers for PCR amplification.The sequencing results showed that the Cassia tora CHS gene is 1 766 bp,containing two exons and one intron.The CHS gene of Cassia tora was submitted to GenBank with an accession number of（JX676773）.The intron is located between 188-765 bp,in line with the GU-AG rule,and contained multiple enzyme digestion sites and cis-regulatory elements which may be involved in expression regulation.The intron of CHS gene had polymorphism,which may be led by the diversity of life history and living environment of different plants.The exon 2 of Cassia tora CHS was more conservative,encoding almost all functional sites of CHS.The NJ phylogenetic evolutionary tree of the amino acid sequence encoded by exon 2,accurately reflect the genetic relationship of the different plants,which can be used in different plant genetic differentiation and molecular evolution research.