Molecular cloning and expression analysis of a MGAPDH homologous gene from mango

Abstract：Glyceral-dehyde-3-phosphate dehyrogenase （GAPDH） is a key enzyme in sugar metabolisn and energy metabolism. PCR primers were designed by the conserved sequenees of GAPDH gene,and full-length cDNA sequence of MGA PDH homologous gene was firstly cloned from Mango by employin RT-PCR and modified RACE technique. The full-length cDNA is 1 356 bp and contains an ORF witl 1 203 bp, corresponding to a deduced protein of 401 amino acids. The results of bioinformatics analysis showed that the estimated molecular weight and isoelectric point of the putative protein were 42.8 ku am 8.9. The protein had two conserved domains, named as NADB_ Rossmann superfamily and Gp dh C superfamily. Bioinformatics analysis also indicated that the protein of mango MGAPDH is a non-secretin protein without any signal peptide and transmembrane domain,MGAPDH gene was located in the chloro plast. The phylogenetic analysis based on the sequence of amino acids showed that MGAPDH protein ma, relative to photosynthesis. Semiquantitative analysis showed that the MGA PDH homologous gene expressec in all tissues of mango, no significant differences in expression levels were founded among the tested tissues; the result indicted that MGAPDH homologous gene may be used as an internal standard for differential gene expression analysis in mango.