True regarding collagen synthesis is all except
The collagen is synthesized by fibroblasts intracellularly, as a large precursor called procollagen.the extracellular procollagen is cleaved by specific peptidases to form tropocollagen. The hydroxylation of proline and lysine residues of collagen is apost- translational modification taking place intracellularly.Prolyl hydrxylase and lusyl hydroxylase are both di-oxygenases using molecular oxygen. The hydroxylated polypeptides are next glycosylated.The glycosylation occurs only on the hydroxylysine residues. Extracellular maturion of collagen occurs. The collagen is arod like structure.Each of the 3 polypeptide chains is held in a helical conformation by winding around each other. REFERENCE : DM VASUDEVAN TEXTBOOK. SEVENTH EDITION ; PAGE NO:721.
Synthesized in ribisomes as preprocollagen
Hydroxylation of proline occurs in Golgi apparatus
Hydroxylation of lysine occurs in ER
Triple helix assembly occurs in ER
Structure and function of protein