Phospholipases and acetylcholinesterases are members of the subclass of esterases. Hydrolyzing phospholipids into a carboxylic acid and a lysophospholipid, the PLA1 and PLA2 (EC 22.214.171.124) esterases differentiate from PLC (EC 126.96.36.199) and PLD (EC 188.8.131.52) which are responsible for cleaving either sites of the phophonate bonds present in phospholipids. Due to the importance of PLA2 in inflammatory responses, regulation of the enzyme is essential. PLA2 is regulated by phosphorylation and calcium concentrations. PLA2 is phosphorylated by a MAPK at Serine-505. When phosphorylation is coupled with an influx of calcium ions, PLA2 becomes stimulated and can translocate to the membrane to begin catalysis.
 Properties and Regulation of Cytosolic Phospholipase A2. C.C. Leslie. J. Biol. Chem. 1997, 272, 16709-16712.