Adhalin (alpha-sarcoglycan) is not required for anchoring of nitric oxide synthase I (NOS I) to the sarcolemma in non-mammalian skeletal (striated) muscle fibers.
Previous studies have shown the association of NOS I with the sarcolemma in mammalian striated muscle fibers, implicating the dystrophin complex (DC) as a major anchor for the enzyme. The potential role of the sarcoglycan subcomplex, especially of alpha-sarcoglycan (adhalin), as part of the DC in holding of NOS I in the sarcolemmal position was examined by carrying out a comparative study on the distribution of NOS I, dystrophin, dystrophin-associated glycoproteins (DAG) and alpha-sarcoglycan in various skeletal muscles of non-mammals. Rat muscles were included since they reflect the situation in mammals. Catalytic NOS-associated diaphorase (NOSaD) activity as well as NOS I and DAG immunoreactivities were positive in the saracolemma region of skeletal muscle fibers of rats, chicken, and turtles. Adhalin immunoreactivity was present in the rat but absent in the chicken and turtle muscle surface membrane. These data suggest that alpha-sarcoglycan and therefore the entire sarcoglycan subcomplex may not be needed for localizing NOS I to the sarcolemma in these non-mammalian species. This may hold for skeletal muscle fibers in general.
Gossrau
R
R
Department of Anatomy, Free University of Berlin, University Clinic Benjamin Franklin, Germany.
Christova
T
T
Grozdanovic
Z
Z
Blottner
D
D
D000818:Animals; D002645:Chickens; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000201:enzymology*; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D049031:Sarcoglycans; D012508:Sarcolemma / Q000201:enzymology; D014426:Turtles
D003598:Cytoskeletal Proteins; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D049031:Sarcoglycans; D019001:Nitric Oxide Synthase