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.