Cloning and sequencing of rainbow trout beta-globin cDNA

beta-Globin cDNA was cloned from a total blood cell cDNA library using carp beta-globin cDNA as the probe. This clone contained an open reading frame of 441 bp that encodes a polypeptide of 147 amino acids. The deduced amino acid sequence showed high identity with teleostei beta-globin. The functionally important residues that are involved in the contacts with the heme or alpha-globin chain were shown to be highly conserved among all vertebrate beta-globin. The structural features and homology analysis indicated that this molecule was an isoform of rainbow trout beta-globin IV. Southern blot analysis using Hind III-digested rainbow trout genomic DNA showed multiple bands and restriction fragment length polymorphism was observed. These results suggest that rainbow trout possesses multiple beta-globin gene family.