Branched-Chain Amino Acid Metabolism Antibody Sampler Kit

Background

BCAT1 and BCAT2 are cytosolic and mitochondrial branched-chain aminotransferases, respectively (1,2). Research studies have implicated BCAT1 in distant metastasis in patients with advanced colorectal cancer (3). Disruption of BCAT2 in mice leads to higher levels of plasma branched-chain amino acids (BCAAs), reduced adiposity and body weight, and increased energy expenditure, suggesting its role in regulating insulin sensitivity (4). BCAAs leucine, isoleucine, and valine are essential amino acids in mammals, but elevated levels of BCAAs have been implicated in cardiovascular and metabolic disorders (5). The branched-chain α-keto acid dehydrogenase complex (BCKDH) catalyzes the rate-limiting step in the BCAA degradation pathway (6,7). Branched-chain α-keto acid decarboxylase (BCKDH-E1) is one of three enzymatic components in this complex (7). The α subunit of BCKDH-E1 (BCKDH-E1α) is critical for the regulation of BCKDH. Phosphorylation of BCKDH-E1α was shown to play a key role in regulating the enzymatic activity of this complex (7-9). Phosphorylation of BCKDH-E1α at Ser293 inactivates BCKDH (7,8). A significant elevation in plasma BCAA levels was reported to correlate with increased phosphorylation of BCKDH-E1α at Ser293 and suppressed BCKDH activity in the liver of diabetic mice (9).