Collagen, type XI, alpha 2

Collagen alpha-2(XI) chain is a protein that in humans is encoded by the COL11A2 gene.

The COL11A2 gene produces one component of this type of collagen, called the pro-alpha2(XI) chain. Type XI collagen adds structure and strength to the tissues that support the body's muscles, joints, organs and skin (the connective tissue). Type XI collagen is normally found in cartilage as well as the fluid that fills the eyeball, the inner ear, and the center portion of the discs between the vertebrae in the spine (nucleus pulposus). Type XI collagen also helps maintain the spacing and diameter of type II collagen fibrils. Type II collagen is an important component of the eye and mature cartilage tissue. The size and arrangement of type II collagen fibrils is essential for the normal structure of these tissues.

The pro-alpha2(XI) chain combines with pro-alpha1(XI) and pro-alpha1(II)collagen chains to form a procollagen molecule. These triple-stranded, ropelike procollagen molecules must be processed by enzymes in the cell. Once processed, these procollagen molecules leave the cell and arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-linkages result in the formation of very strong mature type XI collagen fibers.

The COL11A2 gene is located on the short (p) arm of chromosome 6 at position 21.3, from base pair 33,238,446 to base pair 33,268,222.