Nephrin

Ideogram human chromosome 19

Nephrin

Nephrin is a crucial protein that plays a significant role in the structure and function of the kidney's filtration barrier. It is a key component of the slit diaphragm, a specialized junction between adjacent podocyte foot processes in the kidney glomerulus. This protein is encoded by the NPHS1 gene in humans.

Structure

Nephrin is a transmembrane protein that belongs to the immunoglobulin superfamily. It consists of an extracellular domain with eight Ig-like motifs, a transmembrane domain, and a short cytoplasmic tail. The extracellular domain of nephrin interacts with other proteins in the slit diaphragm, contributing to the maintenance of the glomerular filtration barrier.

Function

Nephrin plays a crucial role in maintaining the integrity of the kidney filtration barrier by regulating the passage of molecules across the glomerular capillaries. It is involved in signaling pathways that control the actin cytoskeleton dynamics in podocytes, which are specialized cells in the kidney responsible for filtration.

Clinical Significance

Mutations in the NPHS1 gene, which encodes nephrin, can lead to a rare genetic disorder called congenital nephrotic syndrome of the Finnish type. This condition is characterized by proteinuria, hypoalbuminemia, and edema in affected individuals. Understanding the role of nephrin in kidney function is essential for developing targeted therapies for kidney diseases.

See also

• Podocyte
• Glomerulus
• Kidney function tests