Pemberton S, Lindley P, Zaitsev V, Card G, Tuddenham E G, Kemball-Cook G
Haemostasis Research Group, Medical Research Council Clinical Sciences Centre, London, UK.
Blood. 1997 Apr 1;89(7):2413-21.
The hemophilia A mutation database lists more than 160 missense mutations: each represents a molecular defect in the FVIII molecule, resulting in the X-linked bleeding disorder hemophilia A with a clinical presentation varying from mild to severe. Without a three-dimensional FVIII structure it is in most cases impossible to explain biological dysfunction in terms of the underlying molecular pathology. However, recently the crystal structure of the homologous human plasma copper-binding protein ceruloplasmin (hCp) has been solved, and the A domains of FVIII share approximately 34% sequence identity with hCp. This advance has enabled the building of a molecular model of the A domains of FVIII based on the sequence identity between the two proteins. The model allows exploration of predictions regarding the general features of the FVIII molecule, such as the binding-sites for factor IXa and activated protein C; it has also allowed the mapping of more than 30 selected mutations with known phenotype from the database, and the prediction of hypothetical links to dysfunction in all but a few cases. A computer-generated molecular model such as that reported here cannot substitute for a crystal structure. However, until such a structure for FVIII becomes available, the model represents a significant advance in modeling FVIII; it should prove a useful tool for exploiting the increasing amount of information in the hemophilia A mutation database, and for selecting appropriate targets for investigation of the structure-function relationships via mutagenesis and expression in vitro.
甲型血友病突变数据库列出了160多种错义突变：每一种都代表FVIII分子中的一种分子缺陷，导致X连锁出血性疾病甲型血友病，其临床表现从轻度到重度不等。由于缺乏FVIII的三维结构，在大多数情况下，不可能从潜在的分子病理学角度解释生物学功能障碍。然而，最近已解析出同源人类血浆铜结合蛋白铜蓝蛋白（hCp）的晶体结构，FVIII的A结构域与hCp具有约34%的序列同一性。这一进展使得能够基于两种蛋白质之间的序列同一性构建FVIII A结构域的分子模型。该模型有助于探索关于FVIII分子一般特征的预测，如与因子IXa和活化蛋白C的结合位点；它还能够对数据库中30多个具有已知表型的选定突变进行定位，并在除少数情况外的所有情况下预测与功能障碍的假设联系。像本文报道的这种计算机生成的分子模型不能替代晶体结构。然而，在FVIII的这种结构可用之前，该模型代表了FVIII建模方面的重大进展；它应该被证明是一种有用的工具，可用于利用甲型血友病突变数据库中越来越多的信息，以及通过体外诱变和表达来选择合适的靶点以研究结构 - 功能关系。
