Pdk4 (pyruvate dehydrogenase kinase, isozyme 4) mediates glucose oxidation through inhibitory phosphorylation of the pyruvate dehydrogenase complex. The pyruvate dehydrogenase complex (PDC) is a mitochondrial matrix enzyme that plays an key role in aerobic energy metabolism by catalyzing the oxidative decarboxylation of pyruvate to form acetyl-CoA for subsequent breakdown in the Krebs cycle. The enzymatic activity of the mammalian PDC is regulated through phosphorylation and desphosphorylation of the E1?subunit of the complex. The enzymes responsible for the phosphorylation and inactivation of the PDC are pyruvate dehydrogenase kinases (PDK1-4). [TISSUE SPECI FICITY] Ubiquitous, highest levels of expression in heart and skeletal muscle. Belongs to the PDK/BCKDK protein kinase family. Contains 1 histidine kinase domain.
