Are cysteine-rich and COOH-terminal domains of dystrophin critical for sarcolemmal localization?
It has been hypothesized that the tight localization of dystrophin at the muscle membrane is carried out by its cysteine-rich and/or carboxyl domains. We report the results of biochemical and immunocytochemical investigations of dystrophin in muscle from a 1-yr-old patient with a large deletion that removes the distal part of the dystrophin gene, thus spanning the exons coding for the cysteine-rich and the carboxy-terminal domains, and extends beyond the glycerol kinase and congenital adrenal hypoplasia genes. Immunological analysis of muscle dystrophin shows that the deletion results in the production of a truncated, but stable, polypeptide correctly localized at the sarcolemma. These data indicate that neither the cysteine-rich domain, nor the carboxyl domain, are necessary for the appearance of normal dystrophin sarcolemmal localization.
Récan
D
D
Institut National de la Santé et de la Recherche Médicale (INSERM) U129, Institut Cochin de Génétique Moléculaire, Paris, France.
Chafey
P
P
Leturcq
F
F
Hugnot
J P
JP
Vincent
N
N
Tomé
F
F
Collin
H
H
Simon
D
D
Czernichow
P
P
Nicholson
L V
LV
D003545:Cysteine / Q000032:analysis; D016189:Dystrophin / Q000032:analysis* / Q000235:genetics; D006801:Humans; D007223:Infant; D008297:Male; D008956:Models, Chemical; D009136:Muscular Dystrophies / Q000378:metabolism*; D012508:Sarcolemma / Q000737:chemistry*
D016189:Dystrophin; D003545:Cysteine