Gelsolin

Gelsolin is a protein that in humans is encoded by the GSN gene. It is an actin-binding protein that plays a crucial role in cellular cytoskeleton organization. Gelsolin is part of the actin depolymerizing factor (ADF)/cofilin protein family.

Structure

Gelsolin is a 82-84 kDa protein that is composed of six homologous Gelsolin-like domains (G1-G6). Each domain contains about 120-130 amino acid residues. The protein has two actin-binding sites, one at the G2/G3 interface and the other at the G4/G6 interface.

Function

Gelsolin is involved in the regulation of actin filament assembly and disassembly. It can sever actin filaments, cap the barbed ends of filaments, and nucleate actin assembly. Gelsolin's activity is regulated by calcium ions and phosphatidylinositol 4,5-bisphosphate (PIP2).

Clinical significance

Mutations in the GSN gene can lead to a rare genetic disorder known as Gelsolin amyloidosis. This condition is characterized by the deposition of gelsolin amyloid fibrils in various tissues, leading to symptoms such as corneal lattice dystrophy, cutis laxa, and peripheral neuropathy.

See also

• Actin
• Cytoskeleton
• Gelsolin amyloidosis