Probably acts as a protein phosphatase. H2O + O-phospho-L-seryl-[protein] = L-seryl-[protein] + phosphate H2O + O-phospho-L-threonyl-[protein] = L-threonyl-[protein] + phosphate Binds 2 manganese ions per subunit. Expression is restricted to neurons. Expressed in AWB, AWC, AVA, AVB, AVX, BAG and URX neurons and in one tail neuron (at protein level). Belongs to the PPP phosphatase family.