BPNT2 is a 3'-nucleotidase that hydrolyzes adenosine 3',5'-bisphosphate (PAP) to AMP and phosphate. Located in the Golgi apparatus and trans-Golgi network, it exhibits 3',5'-nucleotide bisphosphate phosphatase activity. Based on limited published evidence, BPNT2 likely plays roles in: (1) clearing PAP produced during glycosaminoglycan sulfation by Golgi sulfotransferases, supporting endochondral ossification and skeletal development; and (2) regulating intracellular pAp levels for mammalian rapid tRNA decay (mRTD) pathway function under stress conditions 1. Mutations cause chondrodysplasia with joint dislocations, GPAPP type.