Intracellular pool of unhydroxylated polypeptide precursors of collagen.

abstract

• The hydroxyproline and hydroxylysine in collagen are synthesized by an apparently unique pathway in which proline and lysine are hydroxylated after they are incorporated into a large polypeptide precursor of collagen called protocollagen. When the hydroxylation of protocollagen in isolated tissues is intermittently interrupted, hydroxylation can occur after complete polypeptides are released from ribosomal complexes. Cartilage from chick embryos was incubated with the iron chelator alpha,alpha'-dipyridyl for 2 hours to inhibit protocollagen hydroxylase, and then the inhibition was reversed by transferring the tissues to medium containing ferrous iron and no alpha,alpha'-dipyridyl. "Pulse labeling" of the tissues during these two periods indicated that both the accumulated protocollagen and the polypeptides synthesized after reversal of the inhibition were hydroxylated at the same rate. Even when no measures are taken to inhibit the hydroxylation of protocollagen, most of the hydroxyproline in collagen is probably synthesized after complete protocollagen polypeptides are released from ribosomes.

published proceedings

• Science

author list (cited authors)

• Bhatnagar, R. S., Prockop, D. J., & Rosenbloom, J.

citation count

• 33

complete list of authors

• Bhatnagar, RS||Prockop, DJ||Rosenbloom, J

publication date

• October 1967

publisher

• American Association for the Advancement of Science (AAAS)  Publisher

published in

• Science  Journal

keywords

• Animals
• Bone And Bones
• Carbon Isotopes
• Chelating Agents
• Chick Embryo
• Collagen
• Culture Techniques
• Hydroxyproline
• Lysine
• Mixed Function Oxygenases
• Peptide Biosynthesis
• Peptides
• Proline
• Pyridines
• Ribosomes
• Tibia

PubMed Central ID

• 6048104

Digital Object Identifier (DOI)

• 10.1126/science.158.3800.492

start page

• 492

end page

• 494

volume

• 158

issue

• 3800

URL

• http://dx.doi.org/10.1126/science.158.3800.492