Defective folding and stable association with protein disulfide isomerase/prolyl hydroxylase of type I procollagen with a deletion in the pro alpha 2(I) chain that preserves the Gly-X-Y repeat pattern

J Biol Chem. 1992 Apr 15;267(11):7751-7.

Abstract

We have studied the folding, processing, and association with two endoplasmic reticulum (ER) resident proteins of the abnormal type I procollagen molecules produced by a strain of fibroblasts harboring a 4.5 kilobase deletion in an allele of COL1A2 (Willing, M. C., Cohn, D.H., Starman, B. Holbrook, K.A., Greenberg, C.R., and Byers, P.H. (1988) J. Biol. Chem. 263, 8398-8404). By sequencing cDNA, we found that the mutant allele encodes pro alpha 2(I) chains that are shortened by 180 amino acids but retain the Gly-X-Y repeat pattern crucial for collagen triple helix formation. The type I procollagen molecules that incorporated the shortened chain were retained intracellularly and were stable. The triple helical domain in these molecules did not attain a normal conformation and remained accessible to posttranslational modifying enzymes amino-terminal to the deletion site for a prolonged period. The abnormal molecules folded into a triple helical conformation more slowly than the normal molecules, and the amino-terminal ends of the pro alpha 1(I) chains failed to become protease-resistant. While the abnormal procollagen molecules were not bound by the ER-resident protein BiP, they stably associated with protein disulfide isomerase, the beta-subunit of prolyl-4-hydroxylase. These results indicate that some mutations in type I collagen genes both transiently delay folding and permanently disrupt the structure of the triple helix and suggest that binding to prolyl-4-hydroxylase helps to retain certain abnormal procollagen molecules within the ER.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Base Sequence
  • Chromosome Deletion*
  • Cyanogen Bromide
  • DNA / genetics
  • Electrophoresis, Gel, Pulsed-Field
  • Electrophoresis, Polyacrylamide Gel
  • Female
  • Humans
  • Infant
  • Isomerases / genetics*
  • Isomerases / metabolism
  • Molecular Sequence Data
  • Peptide Mapping
  • Procollagen / genetics*
  • Procollagen / metabolism
  • Procollagen-Proline Dioxygenase / genetics*
  • Procollagen-Proline Dioxygenase / metabolism
  • Protein Conformation
  • Protein Disulfide-Isomerases
  • Protein Processing, Post-Translational
  • Repetitive Sequences, Nucleic Acid

Substances

  • Procollagen
  • DNA
  • Procollagen-Proline Dioxygenase
  • Isomerases
  • Protein Disulfide-Isomerases
  • Cyanogen Bromide

Associated data

  • GENBANK/L01675
  • GENBANK/L01676
  • GENBANK/L01677
  • GENBANK/M81726
  • GENBANK/M83679
  • GENBANK/M83680
  • GENBANK/M83681
  • GENBANK/M83724
  • GENBANK/S96821
  • GENBANK/X53709