These domains vary in length and composition and provide flexibility and additional binding sites for other components of the extracellular matrix. There are eight known types of FACIT collagens: collagens IX, XII, XIV, XVI, XIX, XXI, and XXII.
These domains vary in length and composition, offering flexibility and additional binding sites for other components of the extracellular matrix. Collagen types IX, XII, XIV, XVI, XIX, XXI, and XXII are known to be part of this system.