Podocyte dysfunction
We study the glomerular podocyte, a critical cell in forming the kidney's ultrafiltration barrier. Podocyte injury occurs in all forms of proteinuric renal disease and is critical in mediating progression of renal failure. We have identified the sidekick gene family as being highly upregulated in podocytes in HIV-associated nephropathy (HIVAN). We have shown that the sidekicks function as homophilic adhesion molecules and that their over-expression in HIVAN alters how adjacent podocytes interact. We are interested in understanding how the sidekicks contribute to renal failure pathogenesis in both HIVAN and in other renal diseases.

Renal development
The sidekicks are highly expressed in many organs during embryogenesis. In the developing kidney, they are expressed throughout the branching ureteric bud. By using an siRNA based approach, we are studying the role of the sidekick proteins during nephrogenesis and how the sidekicks interact with other critical mediators of ureteric bud branching.

Kaufman L, Hayashi K, Ross MJ, Ross MD, Klotman PE. Sidekick-1 is upregulated in glomeruli in HIV-associated nephropathy. J Am Soc Nephrol 2004 Jul; 15(7): 1721-30.

Hayashi K, Kaufman L, Ross MD, Klotman PE. Definition of the critical domains required for homophilic targeting of mouse sidekick molecules. FASEB J 2005 Apr; 19(6): 614-6.