Evidence that acetyl-CoA carboxylase isoforms play different biological roles in H9c2 cardiomyocyte.
The present work was performed to identify the possible roles of acetyl-CoA carboxylase isoforms (ACC-alpha and ACC-beta). Two forms show 70% amino acid identity, but N-terminal regions share no homology, indicating that these may be uniquely related to the specific role of each ACC form. Thus, we investigated whether introduction of the exogenous ACC N-terminus into H9c2 cardiomyocytes that express both ACC forms causes a noticeable change in a specific pathway of fatty acid metabolism. The effect of ACC-alpha N-terminus overexpression was specific to the fatty acid synthesis rate resulting in an 80% induction, whereas overexpression of the ACC-beta N-terminus increased fatty acid oxidation rate 50% without affecting the fatty acid synthesis rate. These results suggest that ACC-alpha and beta are involved in the regulation of fatty acid synthesis and oxidation, respectively, and that the N-terminus plays an important role in the process. We further demonstrated that novel proteins specifically bound to the ACC N-terminus. This interaction may mediate the involvement of each ACC form in different cellular activities.
Department of Chemistry, Hanyang University, Seoul, Korea.
J M
JM
Kim
M
M
Yoon
I
I
Kang
S S
SS
Kim
J
J
Ha
D000085:Acetates / Q000378:metabolism; D000103:Acetyl-CoA Carboxylase / Q000096:biosynthesis / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D018076:DNA, Complementary; D005227:Fatty Acids / Q000096:biosynthesis; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000201:enzymology; D009206:Myocardium / Q000378:metabolism*; D019308:Palmitic Acid / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D014162:Transfection
D000085:Acetates; D018076:DNA, Complementary; D005227:Fatty Acids; D007527:Isoenzymes; D011994:Recombinant Proteins; D019308:Palmitic Acid; D000103:Acetyl-CoA Carboxylase