IDH3B

Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses, one of which utilizes NAD(+) as the electron acceptor and the other NADP(+). 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 mitochondrial and the other predominantly cytosolic. NAD(+)-dependent isocitrate dehydrogenases catalyze the allosterically regulated rate-limiting step of the tricarboxylic acid cycle. Each isozyme is a heterotetramer that is composed of two alpha subunits, one beta subunit, and one gamma subunit. The protein encoded by this gene is the beta subunit of one isozyme of NAD(+)-dependent isocitrate dehydrogenase. Multiple alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Sep 2016]

异柠檬酸脱氢酶催化异柠檬酸氧化脱羧生成2-氧代戊二酸。这些酶分为两个不同的亚类，其中一类以NAD(+)作为电子受体，另一类以NADP(+)作为电子受体。目前已报道五种异柠檬酸脱氢酶：三种NAD(+)-依赖性异柠檬酸脱氢酶定位于线粒体基质，两种NADP(+)-依赖性异柠檬酸脱氢酶，其中一种定位于线粒体，另一种主要位于细胞质。NAD(+)-依赖性异柠檬酸脱氢酶催化三羧酸循环中的关键限速步骤的变构调节速率。每种同工酶是由两个α亚基、一个β亚基和一个γ亚基组成的异四聚体。由该基因编码的蛋白质是NAD(+)-依赖性异柠檬酸脱氢酶某一同工酶的β亚基。对于该基因，已描述了多种不同的剪接转录变体，它们编码不同的同源形式。[由RefSeq提供，2016年9月]