Kurosaka D, Hattori S, Hori H, Yamaguchi N, Hasegawa T, Akimoto H, Nagai Y
Department of Tissue Physiology, Tokyo Medical and Dental University.
J Biochem. 1994 May;115(5):853-7. doi: 10.1093/oxfordjournals.jbchem.a124429.
Procollagen synthesized by skin fibroblasts from a patient with a lethal variant of osteogenesis imperfecta has been characterized. After pepsin digestion of the type I procollagen, a portion of the alpha 1(I) chains was recovered as a disulfide-bonded dimer. Cyanogen bromide peptide mapping suggested that a new cysteine residue was present in the alpha 1(I)CB6 fragment. Sequencing of cloned cDNAs prepared using mRNA from the proband's fibroblasts demonstrated that some of the clones contained a single base mutation that converted the glycine codon in amino acid position 946 of the alpha 1(I) chain to a cysteine codon. The thermal stability of the molecules was markedly lower than that in the case of the normal control.
对一名患有致死性成骨不全变异型患者的皮肤成纤维细胞合成的前胶原进行了表征。用胃蛋白酶消化I型前胶原后，一部分α1(I)链以二硫键连接的二聚体形式回收。溴化氰肽图谱分析表明，α1(I)CB6片段中存在一个新的半胱氨酸残基。使用先证者成纤维细胞的mRNA制备的克隆cDNA测序表明，一些克隆含有单个碱基突变，该突变将α1(I)链第946位氨基酸的甘氨酸密码子转换为半胱氨酸密码子。这些分子的热稳定性明显低于正常对照。
