Patatin-like phospholipase domain containing protein 6 and protein 7
Patatin-like phospholipase domain containing protein 6 (PNPLA6) and protein 7 (PNPLA7) are 60% identical to each other. PNPLA6 is commonly known as Neuropathy Target Esterase (NTE). NTE has at least two functional domains: the N-terminal domain putatively regulatory domain and the C-terminal catalytic domain which shows esterase activity. NTE shows phospholipase activity for lysophosphatidylcholine (LPC) and phosphatidylcholine (PC). Exposure of NTE to organophosphates leads to organophosphate-induced delayed neurotoxicity (OPIDN). OPIDN is a progressive neurological condition that is characterized by weakness, paralysis, pain, and paresthesia. PNPLA7 is an insulin-regulated phospholipase that is homologous to Neuropathy Target Esterase (NTE or PNPLA6) and is also known as NTE-related esterase (NRE). Human NRE is predominantly expressed in prostate, white adipose, and pancreatic tissue. NRE hydrolyzes sn-1 esters in lysophosphatidylcholine and lysophosphatidic acid, but shows no lipase activity with substrates like triacylglycerols (TG), cholesteryl esters, retinyl esters (RE), phosphatidylcholine (PC), or monoacylglycerol (MG). This family includes PNPLA6 and PNPLA7 from Homo sapiens, YMF9 from Yeast, and Swiss Cheese protein (sws) from Drosophila melanogaster.