Mapping of the phosphorylase kinase alpha subunit gene on the mouse X chromosome

Abstract

Phosphorylase kinase is a glycogenolytic enzyme in several animal tissues. Within the last few years all four subunits of the enzyme have been cloned. The β, γ, and δ subunits are known to be autosomal. We have mapped the α subunit of phosphorylase kinase, recently cloned by Zander et al. (1988), in an interspecific mouse pedigree and localized it on the X chromosome, where it maps between the X-linked zinc finger protein and phosphogly cerate kinase genes, close to the latter. In man and mouse several X-linked disorders of this enzyme have been described. Although the X-linked phosphorylase kinase deficiency in mice may be caused by a mutation in the structural gene for the α subunit, mapped here, the existence of a separate regulatory locus, important in the normal expression or function of the enzyme in muscle, still remains a possibility.