title: Isolation of cDNA clones for the catalytic gamma subunit of mouse muscle phosphorylase kinase: expression of mRNA in normal and mutant Phk mice.
abstract: We have isolated and characterized cDNA clones for the gamma subunit of mouse muscle phosphorylase kinase (gamma-Phk). These clones were isolated from a lambda gt11 mouse muscle cDNA library via screening with a synthetic oligonucleotide probe corresponding to a portion of the rabbit gamma-Phk amino acid sequence. The gamma-Phk cDNA clones code for a 387-amino acid protein that shares 93% amino acid sequence identity with the corresponding rabbit amino acid sequence. RNA gel blot analysis reveals that the muscle gamma-Phk probe hybridizes to two mRNA species (2.4 and 1.6 kilobases) in skeletal muscle, cardiac muscle, and brain, but does not hybridize to liver RNA. Phk-deficient I-strain (Phk) mouse muscle contains reduced levels of gamma-Phk mRNA as compared with control mice. Although the Phk defect is an X-linked recessive trait, hybridization to a human-rodent somatic cell hybrid mapping panel shows that the gamma-Phk gene is not located on the X chromosome. Rather, the gamma-Phk cross-hybridizing human restriction fragments map to human chromosomes 7 (multiple) and 11 (single). Reduced gamma-Phk mRNA in I-strain mice, therefore, appears to be a consequence of the Phk-mutant trait and does not stem from a mutant gamma-subunit gene.
authors.forename: J S
authors.initials: JS
authors.lastname: Chamberlain
authors.forename: P
authors.initials: P
authors.lastname: VanTuinen
authors.forename: A A
authors.initials: AA
authors.lastname: Reeves
authors.forename: B A
authors.initials: BA
authors.lastname: Philip
authors.forename: C T
authors.initials: CT
authors.lastname: Caskey
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification*; D005796:Genes; D006801:Humans; D006822:Hybrid Cells / Q000201:enzymology; D046911:Macromolecular Substances; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D009132:Muscles / Q000201:enzymology; D009154:Mutation; D009693:Nucleic Acid Hybridization; D010764:Phosphorylase Kinase / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D046911:Macromolecular Substances; D012333:RNA, Messenger; D004247:DNA; D010764:Phosphorylase Kinase