Substitution of cysteine for glycine at residue 415 of one allele of the alpha 1(I) chain of type I procollagen in type III/IV osteogenesis imperfecta
Autor: | D V Renouf, JE Oliver, A C Nicholls, M Keston, F M Pope |
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Rok vydání: | 1991 |
Předmět: |
Male
Mutant Molecular Sequence Data Biology medicine.disease_cause Peptide Mapping Genetics medicine Humans Amino Acid Sequence Peptide sequence Genetics (clinical) Alleles Mutation Base Sequence DNA Middle Aged Osteogenesis Imperfecta Molecular biology Procollagen peptidase Biochemistry Glycine Type I collagen Procollagen Triple helix Cysteine Research Article |
Zdroj: | Journal of medical genetics. 28(11) |
ISSN: | 0022-2593 |
Popis: | We have examined the type I collagen in a patient with type III/IV osteogenesis imperfecta. Two forms of alpha 1(I) chain were produced, one normal and the other containing a cysteine residue within the triple helical domain of the molecule. Cysteine is not normally present in this domain of type I collagen. Peptide mapping experiments localised the mutation to peptide alpha 1(I)CB3 which spans residues 403 to 551 of the triple helix. Subsequent PCR amplification of cDNA covering this region followed by sequencing showed a G to T single base change in the GGC codon for glycine 415 generating TGC, the codon for cysteine. The effect of the mutation on the protein is to delay secretion from the cell, reduce the thermal stability of the molecule by 2 degrees C, and cause excessive post-translational modification of all chains in molecules containing one or more mutant alpha 1(I) chains. The clinical phenotype observed in this patient and the position of the mutation conform to the recent prediction of Starman et al that Gly----Cys mutations in the alpha 1(I) chain have a gradient of severity decreasing from the C-terminus to the N-terminus. |
Databáze: | OpenAIRE |
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