title: Increased expression of the gene for the pro alpha 1(IV) chain of basement-membrane procollagen in cultured skin fibroblasts from two variants of osteogenesis imperfecta.
abstract: Fibroblasts from two lethal variants of osteogenesis imperfecta were shown to synthesize increased amounts of type IV procollagen. Previous studies established that one of these variants had a non-functional allele for the pro alpha 2 chain of type I procollagen, whereas the other pro alpha 2(I) allele contained a mutation leading to synthesis of shortened pro alpha 2(I) chains. In the two variants, the relative level of mRNA for pro alpha 1(IV) was 31 and 42% of the level of mRNA for pro alpha 1(I) chains. A value of less than 2% was found for a third lethal and four non-lethal variants of osteogenesis imperfecta. Immunofluorescent staining of fibroblasts from the two variants synthesizing increased amounts of type IV procollagen indicated that a homogeneous population of cells synthesized both type IV and type I procollagen. The results suggest that mutations in the type I procollagen genes that result in osteogenesis imperfecta can be associated with increased expression of the genes for type IV procollagen.
authors.affiliation: Collagen Research Unit, University of Oulu, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Pihlajaniemi
authors.forename: J
authors.initials: J
authors.lastname: McKeon
authors.forename: S
authors.initials: S
authors.lastname: Gay
authors.forename: R
authors.initials: R
authors.lastname: Gay
authors.forename: W J
authors.initials: WJ
authors.lastname: de Wet
authors.forename: J C
authors.initials: JC
authors.lastname: Myers
authors.forename: D J
authors.initials: DJ
authors.lastname: Prockop
mesh_terms: D001485:Basement Membrane; D015152:Blotting, Northern; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D006801:Humans; D009154:Mutation; D010013:Osteogenesis Imperfecta / Q000235:genetics*; D011347:Procollagen / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D012867:Skin / Q000378:metabolism
chemical_list: D011347:Procollagen; D012333:RNA, Messenger