Pleomorphism in type I collagen fibrils produced by persistence of the procollagen N-propeptide. Academic Article uri icon

abstract

  • The assembly of type I collagen and type I pN-collagen was studied in vitro using a system for generating these molecules enzymatically from their immediate biosynthetic precursors. Collagen generated by C-proteinase digestion of pC-collagen formed D-periodically banded fibrils that were essentially cylindrical (i.e. circular in cross-section). In contrast, pN-collagen generated by C-proteinase digestion of procollagen formed thin, sheet-like structures that were axially D-periodic in longitudinal section, of varying lateral widths (up to several microns) and uniform in thickness (approximately 8 nm). Mixtures of collagen and pN-collagen assembled to form a variety of pleomorphic fibrils. With increasing pN-collagen content, fibril cross-sections were progressively distorted from circular to lobulated to thin and branched structures. Some of these structures were similar to fibrils observed in certain heritable disorders of connective tissue where N-terminal procollagen processing is defective. The observations are considered in terms of the hypothesis that the N-propeptides are preferentially located on the surface of a growing assembly. The implications for normal diameter control of collagen fibrils in vivo are discussed.

published proceedings

  • J Mol Biol

author list (cited authors)

  • Hulmes, D. J., Kadler, K. E., Mould, A. P., Hojima, Y., Holmes, D. F., Cummings, C., Chapman, J. A., & Prockop, D. J.

citation count

  • 73

complete list of authors

  • Hulmes, DJ||Kadler, KE||Mould, AP||Hojima, Y||Holmes, DF||Cummings, C||Chapman, JA||Prockop, DJ

publication date

  • November 1989