Short-chain acyl-coenzyme A dehydrogenase activity, antigen, and biosynthesis are absent in the BALB/cByJ mouse.
BALB/cByJ (J) mice have short-chain acyl-CoA dehydrogenase (SCAD) deficiency and an organic aciduria similar to that of human SCAD deficiency. [9,10(n)-3H]- and [15,16(n)-3H]palmitate oxidations in J mouse fibroblasts were 96 and 35% of control, respectively, consistent with an isolated SCAD defect. Acyl-CoA dehydrogenase activities were assayed in muscle and fibroblast mitochondria from BALB/cBy controls (Y) and SCAD-deficient J mice. Medium-chain acyl-CoA dehydrogenase (MCAD) activities were comparable in both J and Y mice from all tissues. In the presence of MCAD antiserum, SCAD activities in J mice were undetectable in both tissues. Apparent Km and Vmax values in liver mitochondria suggested a somewhat increased affinity of MCAD for butyryl-CoA in J mice, as compared with MCAD from other species. Immunoblot studies using mitochondria revealed identical apparent SCAD molecular weight in liver, muscle, and fibroblasts from Y mice and no detectable SCAD antigen in J mice; MCAD antigen was detected in comparable amounts from both Y and J mice. Radiolabeling and immunoprecipitation studies in J mouse fibroblasts revealed no SCAD synthesis, but normal MCAD synthesis. These data argue against the existence of tissue-specific SCAD isoforms in the mouse and confirm that this mouse strain is a model for the human organic aciduria resulting from this beta-oxidation defect.
Amendt
B A
BA
Department of Pediatrics, University of Iowa, Iowa City 52242.
Freneaux
E
E
Reece
C
C
Wood
P A
PA
Rhead
W J
WJ
D042964:Acyl-CoA Dehydrogenase; D044944:Acyl-CoA Dehydrogenases / Q000172:deficiency* / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D000818:Animals; D000941:Antigens / Q000032:analysis; D005347:Fibroblasts / Q000201:enzymology; D007120:Immunochemistry; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D051379:Mice; D008807:Mice, Inbred BALB C; D008817:Mice, Mutant Strains; D009132:Muscles / Q000201:enzymology; D014018:Tissue Distribution
D000941:Antigens; D044944:Acyl-CoA Dehydrogenases; D042964:Acyl-CoA Dehydrogenase