Cloning and Sequencing of an Expansin cDNA Fragment in Banana Fruit

Using PCR degenerate primers designed with reference to the conserved amino acid sequences of known expansins to amplify cDNA fragments in banana fruit by RTPCR, a new cDNA fragment named MAExp3 was cloned, whose fragment was 531 bp encoding 177 amino acids; 8 cysteine residues and 3 tryptophan residues which are supposed to be the characteristics of expansins are conserved in MAExp3;MAExp3 shared 742% and 864% homologue with MAExp1 at nucleotide and amino acid levels, respectively.