Collagen Synthesis

 

Collagen Synthesis: The Multistep Process

Collagen synthesis occurs in both the intracellular and extracellular spaces. Defects at any stage result in connective tissue disorders.

Stage Location Process Details
Translation RER Synthesis of preprocollagen (Glycine-X-Y repeats).
Hydroxylation RER Proline/lysine hydroxylation (requires Vitamin C).
Glycosylation RER Formation of procollagen triple helix; exocytosis.
Cleavage Extracellular Procollagen peptidases cleave N- and C-terminal ends (forms tropocollagen).
Cross-linking Extracellular Lysyl oxidase (requires Copper) creates covalent cross-links.
High-Yield Core Realities:

  • Vitamin C Deficiency: Causes Scurvy; inability to hydroxylate proline/lysine prevents stable triple helix formation.
  • Copper Deficiency: Inhibits lysyl oxidase, resulting in cross-linking defects (e.g., Menkes disease).
  • Osteogenesis Imperfecta: Often caused by mutations in the genes coding for Type I collagen.