SMPDL3B and focal segmental glomerulosclerosis: We furthermore showed that the expression of SMPDL3b which acts as a potential C1P phosphatase [29,30] is decreased in podocytes of patients with recurrence of FSGS after transplantation [121], while overexpression of SMPDL3b in podocytes prevents actin cytoskeleton disruption and apoptosis [121].