Actin-binding protein found in the cytoplasm of vertebrate cells, which has a length-limiting effect on actin filaments. Gelsolin is similar in structure and function to villin.
The protein is encoded by a gene located on chromosome 2: 35.26 - 35.31. Mutations of the gene lead to a rare hereditary systemic amyloidosis (AGel) with corneal opacities (H17.1) and polyneuropathy ( G62.-)
At certain Ca2+ concentrations, the protein binds to the end of the actin filament (the site of F-actin elongation) It thereby causes the filaments to dissolve and prevents repolymerisation. Gelsolin is found in the cytosol and in mitochondria of the cell as well as extracellularly in blood plasma