Podocin (NPHS2)

Podocin is an integral membrane protein of 383 amino acids encoded by the NPHS2 gene and is a critical structural component of the glomerular slit diaphragm in kidney podocytes[5][6][2][3][8]. It is a member of the band-7-stomatin protein family and features a hairpin-like transmembrane domain, with both the N- and C-termini in the cytoplasm[5][1][6]. Podocin oligomerizes in cholesterol- and sphingolipid-rich lipid rafts at the podocyte foot processes to assemble a multiprotein complex that forms the filtration slit. Its C-terminal region interacts with crucial slit diaphragm proteins such as nephrin, CD2AP, and NEPH1, anchoring the complex to the cytoskeleton and stabilizing the glomerular filtration barrier[2][3][4][1][7]. Mutations in podocin (NPHS2) lead to various forms of steroid-resistant nephrotic syndrome, particularly in children, because they disrupt the slit diaphragm’s integrity, causing massive proteinuria and progression to chronic kidney disease[5][3][8]. Podocin is currently not a therapeutic target for drugs, but NPHS2 mutations serve as genetic biomarkers for disease diagnosis and prognosis. Besides the kidney, restricted podocin expression has also been demonstrated in Sertoli cells of the testis, suggesting a possible role in the blood-testis barrier[3].

Other names

Nephrosis 2, idiopathic, steroid-resistant (podocin)NPHS2Nephrosis 2 protein