The transgene consists of a mutant mouse cDNA, with an engineered substitution changing isoleucine codon 1127 into an alanine codon (p.Ile1127Ala), under the control of the mouse alpha myosin heavy chain promoter. Immunoblot assays indicate that the expression from this allele is around 5-fold higher than expression from the endogenous gene. The affected codon codes for the isoleucine crucial for the actin binding function of the peptide. (J:262067)