title: Deposition of mutant type I collagen in the extracellular matrix of cultured dermal fibroblasts in osteogenesis imperfecta.
abstract: To study how mutant type I collagen interferes with matrix deposition we investigated the extracellular matrix produced by cultured skin fibroblasts in thirteen patients affected by different forms of Osteogenesis Imperfecta. Two different approaches were used: a) the pericellular matrix produced during 24 h label was analyzed by SDS-PAGE; b) type I collagen present in the insoluble cell-layer fraction in long-term cultures was studied. Results showed that a very small amount of abnormal type I trimers were present regardless of the clinical phenotype. In only two cases mutant chains were clearly incorporated. These data indicate a selective deposition of normal collagen trimers over abnormal ones. Moreover, in long-term cultures a decreased amount of type I collagen was deposited as indicated by the relative increase in type V collagen. These data are discussed in light of results found in bone by other authors and suggest that decreased deposition of type I collagen could be a general feature in OI and not limited to null-allele OI probands.
authors.affiliation: Dipartimento di Biochimica, Università di Pavia, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cetta
authors.forename: A
authors.initials: A
authors.lastname: Rossi
authors.forename: R
authors.initials: R
authors.lastname: Tenni
authors.forename: M
authors.initials: M
authors.lastname: Valli
authors.forename: A
authors.initials: A
authors.lastname: Forlino
authors.forename: G
authors.initials: G
authors.lastname: Zanaboni
authors.forename: K
authors.initials: K
authors.lastname: Dyne
authors.forename: G R
authors.initials: GR
authors.lastname: Burgio
mesh_terms: D002478:Cells, Cultured; D003094:Collagen / Q000032:analysis / Q000235:genetics* / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005109:Extracellular Matrix / Q000737:chemistry / Q000378:metabolism*; D005347:Fibroblasts / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D009154:Mutation / Q000235:genetics*; D010013:Osteogenesis Imperfecta / Q000378:metabolism* / Q000473:pathology*; D010449:Peptide Mapping; D010641:Phenotype; D012867:Skin / Q000473:pathology*
chemical_list: D003094:Collagen