Cartilage-associated protein (CRTAP)

Cartilage-associated protein (CRTAP) is a non-enzymatic structural and scaffolding protein, closely related to the Leprecan family, and is encoded by the CRTAP gene in humans. CRTAP forms a complex in the endoplasmic reticulum with prolyl 3-hydroxylase 1 (P3H1/LEPRE1) and cyclophilin B (PPIB). This complex is essential for the 3-hydroxylation of proline residues in fibrillar collagens (types I, II, and V), a post-translational modification necessary for proper collagen folding, stability, and extracellular matrix organization. CRTAP mutations cause specific recessive forms of osteogenesis imperfecta, a disease characterized by bone fragility, low bone mass, and connective tissue abnormalities. CRTAP itself is not a classical druggable therapeutic target (e.g., enzyme, receptor, transporter), and there are no known drugs that interact directly with it.

Other names

CASPLEPREL3OI7P3H5cartilage associated proteinleprecan-like 3prolyl 3-hydroxylase family member 5 (non-enzymatic)