title: Induction of the branched-chain 2-oxo acid dehydrogenase complex in 3T3-L1 adipocytes during differentiation.
abstract: The activities of 2-oxo acid dehydrogenase complexes were measured during hormone-mediated differentiation of 3T3-L1 preadipocytes into adipocytes. Specific activity of leucine-activated branched-chain 2-oxo acid dehydrogenase complex increased approx. 10-fold in 3T3-L1 adipocytes compared with 3T3-L1 preadipocytes. In contrast, specific activity of the 2-oxoglutarate dehydrogenase complex increased by only 3-fold in 3T3-L1 adipocytes. The three catalytic component enzymes of the branched-chain 2-oxo acid dehydrogenase complex and the pyruvate dehydrogenase complex showed concomitant increases in their specific activities. A close similarity in kinetics of induction of the branched-chain 2-oxo acid dehydrogenase complex and the pyruvate dehydrogenase complex in 3T3-L1 adipocytes suggests that a common mechanism may be involved in hormone-dependent increases in the activities of the catalytic components of these two complexes in 3T3-L1 adipocytes during differentiation.
mesh_terms: D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide); D000273:Adipose Tissue / Q000166:cytology / Q000201:enzymology*; D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D004790:Enzyme Induction; D007655:Ketoglutarate Dehydrogenase Complex / Q000096:biosynthesis; D007658:Ketone Oxidoreductases / Q000096:biosynthesis*; D051379:Mice; D009097:Multienzyme Complexes / Q000096:biosynthesis*; D011768:Pyruvate Dehydrogenase Complex / Q000096:biosynthesis
chemical_list: D009097:Multienzyme Complexes; D011768:Pyruvate Dehydrogenase Complex; D007658:Ketone Oxidoreductases; D007655:Ketoglutarate Dehydrogenase Complex; D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)