Which of the following are intracellular events occurring in fibroblast during synthesis of collagen-: (A) Hydrolysis of procollagen to collagen, (B) Glycosylation of proline, (C) Formation of triple helix, (D) Formation of covalent cross link b/w fibrils
Answer is C. Formation of triple helix (of pre-a-chains) takes place intracellularly in RER.
Formation of a cross-link between fibrils (i.e. self-assembly of tropocollagen monomers into mature collagen fiber) occurs extracellularly after secretion from fibroblasts.
Glycosylation also occurs intracellularly, but its glycosylation of hydroxylysine (not of proline).