Cloning, nucleotide sequence and characterization of a full-length cDNA encoding the myosin heavy chain from adult chicken pectoralis major muscle.

Four cDNA clones, encoding the chicken adult sarcomeric MyHC, have been isolated from a pectoralis major muscle cDNA library using gene-specific DNA probes. These clones were sequenced and then subcloned into a full-length, 6-kb, chicken adult sarcomeric MyHC cDNA. The entire cDNA consists of 5873 nucleotides with 19 bp 5'-untranslated region and 34 bp 3'-untranslated region. The complete cDNA encodes a 1939-aa polypeptide whose molecular weight is 223 kDa. The calculated isoelectric point of this protein is approximately 5.7. Analysis of the deduced amino acid sequence and comparison with a previously published amino-acid sequence of the same MyHC isoform reveals that six amino acid residues are different. Hydrophilicity analysis of this adult MyHC amino-acid sequence shows a similar pattern as the embryonic MyHC. A recombinant baculovirus, carrying this full-length adult MyHC cDNA, has also been generated and expressed in the Sf9 insect cell line. A approximately 220-kDa recombinant MyHC was synthesized and reacted specifically with chicken adult MyHC monoclonal antibodies.