PIK3C3 and glomerulosclerosis: Deletion of a key endosomal trafficking regulator, the class III phosphatidylinositol (PtdIns) 3-kinase vacuolar protein sorting 34 (Vps34), specifically in podocytes results in aberrant endosomal membrane morphology, early proteinuria, glomerulosclerosis, and foot process effacement (17–19).