Reactions grouped in this pathway because of their shared chemistry - the hydrolysis of various phosphatidyl inositols and related phospholipids. They differ, however, in the tissues in which they occur and in their likely physiological roles. The activities of PNPLA6 and GDPD5 annotated here, for example, are especially prominent in kidney cells where the choline they generate plays a role in protecting cells from osmotic stress (Burg et al. 2007). Expression of others may be correlated with specific developmental events (Corda et al. 2013).