甘菊BADH基因cDNA的克隆及在盐胁迫下的表达

利用PCR、RT-PCR和PCR-RACE技术,从菊科植物甘菊(Dendranthema lavandulifolium)中克隆到2个甜菜碱醛脱氢酶(betaine aldehyde dehydrogenase,BADH)基因的同源基因,分别命名为DlBADH1和DlBADH2,GenBank登录号分别为DQ011151和DQ011152。DlBADH1的cDNA全长1821 bp,其开放阅读框编码503个氨基酸的蛋白质;DlBADH2全长1918 bp,编码506个氨基酸的蛋白质。两个基因核苷酸序列的同源性为97%,推导的氨基酸序列的同源性为98%。与已发表的其它植物BADH基因氨基酸序列的同源性在64%以上。在推导的氨基酸序列中,均含有醛脱氢酶所具有的高度保守的十肽(VTLELGGKSP)以及与酶功能有关的半胱氨酸残基(C)。在推导的氨基酸序列的系统关系中,甘菊位于其它双子叶植物和单子叶植物之间,与其植物分类的系统关系相吻合。RT-PCR-Southern半定量表达分析表明,甘菊BADH基因家族中存在表达受盐诱导的成员。

Cloning and Expression Analysis of Betaine Aldehyde Dehydrogenase Gene from Dendranthema lavandulifolium on Salinity

By PCR,RT-PCR and PCR-RACE technique,two novel homologue genes of BADH gene were cloned from Dendranthema lavandulifolium,GenBank accession numbers are DQ011151 and DQ011152.The full length cDNA of DlBADH1 is 1821 bp,encoding 503 amino acids(aa),and the full length of DlBADH2 is 1918 bp,encoding 506 amino acids(aa).The similarity between the two sequences is 97%,and the similarity of the deduced amino acids is 98%.Encoded protein by the two sequences and other published BADH sequences also shared above 64% identity at the amino acid level.The result showed BADH gene was conserved.Both the deduced amino acid sequences contain the conserved decapaptide(VTLELGGKSP) and cysteine residue(C) in aldehyde dehydrogenase(ALDHs).According to the phylogenetic tree of the deduced amino acid sequences,D.lavandulifolium located between other dicotyledon plants and monocotyledon plants,which was identical with the plant taxonomy relationship.Semi-quantitative gene expression analysis by RT-PCR-Southern showed that there was at least a member induced by salt in the family of BADH from D.lavandulifolium.