IDH1 (Isocitrate Dehydrogenase 1) [IDH/1152]

Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses that utilize either NAD or NADP+ as an electron acceptor. Five isocitrate dehydrogenases have been reported: three NAD dependent isocitrate dehydrogenases, which localize to the mitochondrial matrix, and two NADP+ dependent isocitrate dehydrogenases, one of which is found in predominantly cytoplasm and peroxisomes (IDH1) and the other mitochondrial (IDH2). IDH1 and IDH2 are homodimers and key enzymes linking cellular metabolism to epigenetic regulation and redox states. IDH1, a 45kDa protein, catalyzes the third step of the citric acid cycle, which involves the oxidative decarboxylation of isocitrate, forming alpha-ketoglutarate and CO2 in a two-step reaction. The first step involves the oxidation of isocitrate to the intermediate oxalosuccinate, while the second step involves the production of alpha-ketoglutarate. During this process, either NADH or NADPH is produced along with CO2. IDH1 appears to function as a tumor suppressor that, when mutationally inactivated, contributes to tumorigenesis in part through induction of the HIF-1 pathway. This antibody recognizes wild-type IDH1. Recent studies show that primary glioblastoma increases expression of wild-type IDH1, which confers therapeutic resistance.