The deduced protein contains a 38-amino acid signal peptide, followed by a 544-amino acid N-peptide domain, a 931-amino acid triple helix region with one imperfect 4-amino acid insertion characteristic of invertebrate collagens, and a 235-amino acid C-propeptide. The deduced N-peptide domain contains a thrombospondin N-terminal-like (TSPN) motif that shares 27.3% sequence identity with the TSPN motifs of COL5A1 and COL11A1. The COL24A1 N-peptide sequence contains a homolog of a conserved sequence characteristic of fibril diameter-regulating fibrillar collagen chains. COL24A1 is predicted to have a retained N-peptide after processing. Using RT-PCR of adult tissues, Koch et al. (2003) demonstrated that mouse Col24a1 is a nonabundant collagen expressed in bone and retina and to a lesser degree in cornea, skin, and tendon.