title: Characterization and localization of a 77 kDa protein related to the dystrophin gene family.
abstract: The Duchenne muscular dystrophy gene gives rise to transcripts of several lengths. These mRNAs differ in their coding content and tissue distribution. The 14 kb mRNA encodes dystrophin, a 427 kDa protein found in muscle and brain, and the short transcripts described encode DP71, a 77 kDa protein found in various organs. These short transcripts have many features common to the deduced primary structure of dystrophin, especially in the cysteine-rich specific C-terminal domains. The dystrophin C-terminal domain could be involved in membrane anchorage via the glycoprotein complex, but such a functional role for these short transcript products has yet to be demonstrated. Here we report the first isolation of a short transcript product from saponin-solubilized cardiac muscle membranes using alkaline buffer and affinity chromatography procedures. This molecule was found to be glycosylated and could be easily dissociated from cardiac muscle and other non-muscle tissues such as brain and liver. DP71-specific monoclonal antibody helped to identify this molecule as being related to the dystrophin gene family. Immunofluorescence analysis of bovine or chicken cardiac muscle showed a periodic distribution of DP71 in transverse T tubules and this protein was co-localized with the dystrophin glycoprotein complex in the Z-disk area.
authors.affiliation: INSERM U.300, Faculté de Pharmacie, Montpellier, France.
authors.forename: E
authors.initials: E
authors.lastname: Fabbrizio
authors.forename: U
authors.initials: U
authors.lastname: Nudel
authors.forename: G
authors.initials: G
authors.lastname: Hugon
authors.forename: A
authors.initials: A
authors.lastname: Robert
authors.forename: F
authors.initials: F
authors.lastname: Pons
authors.forename: D
authors.initials: D
authors.lastname: Mornet
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D002645:Chickens; D017931:DNA Primers; D016189:Dystrophin / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics*; D006801:Humans; D008099:Liver / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000032:analysis / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009136:Muscular Dystrophies / Q000235:genetics; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D015183:Restriction Mapping; D014158:Transcription, Genetic
chemical_list: D000911:Antibodies, Monoclonal; D017931:DNA Primers; D016189:Dystrophin; D008562:Membrane Glycoproteins; D012333:RNA, Messenger