FYN and focal segmental glomerulosclerosis: Further, Prss23 (4.7 FC) was one of the most strongly upregulated genes in Cd2ap+/-, Fyn-/- mesangial cells, and also one of the most strongly upregulated genes in podocytes of the Cd2ap-/- FSGS model [24], although, interestingly, it was not strongly upregulated in Cd2ap+/-, Fyn-/- podocytes.