Collagen, type X, alpha 1

Collagen, Type X, Alpha 1

Collagen, type X, alpha 1 (COL10A1) is a member of the collagen family of proteins, which are essential components of the extracellular matrix in various tissues. Type X collagen is a short-chain collagen that is primarily expressed in the hypertrophic zone of the growth plate during endochondral ossification, a process critical for the development of long bones.

Structure

Type X collagen is a homotrimer, meaning it is composed of three identical alpha chains, each encoded by the COL10A1 gene. The protein is characterized by a short triple-helical domain flanked by non-collagenous domains at both the N- and C-termini. The unique structure of type X collagen allows it to play a specialized role in cartilage mineralization and the transition of cartilage to bone.

Function

The primary function of type X collagen is to facilitate the mineralization of cartilage and the subsequent replacement of cartilage by bone during endochondral ossification. This process is crucial for the proper formation and growth of long bones, such as the femur and tibia. Type X collagen is specifically expressed by hypertrophic chondrocytes, which are mature cartilage cells that have ceased to proliferate and are preparing for mineralization.

Clinical Significance

Mutations in the COL10A1 gene can lead to a rare skeletal disorder known as Schmid metaphyseal chondrodysplasia (SMCD). This condition is characterized by short stature, bowed legs, and other skeletal abnormalities due to defective endochondral ossification. The study of type X collagen and its genetic mutations provides valuable insights into the molecular mechanisms underlying bone development and growth disorders.

Research and Applications

Research on type X collagen has implications for understanding bone diseases and developing therapeutic strategies. For instance, studying the regulation of COL10A1 expression and the signaling pathways involved in chondrocyte hypertrophy can lead to potential treatments for growth plate disorders and cartilage repair.

Also see

• Collagen
• Endochondral ossification
• Chondrocyte
• Extracellular matrix
• Schmid metaphyseal chondrodysplasia