Collagen, type XVIII, alpha 1

Collagen, type XVIII, alpha 1 is a protein that in humans is encoded by the COL18A1 gene. This protein is a member of the collagen family, which is the most abundant protein in the animal kingdom. Collagen, type XVIII, alpha 1 is a multi-domain, non-fibrillar collagen that plays a crucial role in the maintenance of basement membrane integrity and in the suppression of angiogenesis.

Structure

The COL18A1 gene is located on the long (q) arm of chromosome 21 at position 22.3. The encoded protein, collagen, type XVIII, alpha 1, is composed of three identical alpha chains, each with a unique triple helix domain and a C-terminal endostatin domain. The triple helix domain provides structural stability, while the endostatin domain has been implicated in the inhibition of angiogenesis and tumor growth.

Function

Collagen, type XVIII, alpha 1 is a component of the basement membrane, a thin, sheet-like structure that separates and supports cells in many tissues. The protein also plays a role in the suppression of angiogenesis, the growth of new blood vessels from pre-existing vessels. This is primarily due to the endostatin domain of the protein, which can be cleaved and act as an independent, potent inhibitor of angiogenesis.

Clinical significance

Mutations in the COL18A1 gene have been associated with Knobloch syndrome, a rare genetic disorder characterized by severe vision problems and possible brain anomalies. Additionally, the endostatin domain of collagen, type XVIII, alpha 1 has been studied for its potential use in cancer therapy due to its ability to inhibit tumor growth and angiogenesis.

File:COL18A1 gene location on human chromosome 21.png

Location of the COL18A1 gene on chromosome 21.

See also

• Collagen
• Knobloch syndrome
• Angiogenesis
• Basement membrane