Isolation and characterization of the complete human ?-myosin heavy chain gene

Abstract

The entire gene coding for the human β-myosin heavy chain has been isolated from genomic EMBL3A phage libraries by chromosomal walking starting from clone gMHC-1, reported earlier (Appelhans and Vosberg 1983). gMHC-1 has been shown to carry coding information for the C-terminal two-thirds of β-myosin heavy chain, which is expressed in cardiac muscle and in slow skeletal muscle fibers (Lichter et al. 1986). Three DNA clones were identified as overlapping with gMHC-1 by restriction mapping and DNA sequencing. They span a 30-kb region in the genome. About 22 kb extend from the initiation codon ATG to the poly(A) addition site. The clones include about 4 kb of 5′ flanking sequences upstream of the promoter. Comparisons of β- and α-myosin heavy chain sequences indicate that gene duplication of the cardiac myosin heavy chain isogenes preceded the mammalian species differentiation.