Physiological and biochemical analysis of VWF-cleaving protease ADAMTS13

血浆ADAMTS 13切割血管性血友病因子（VWF）多聚体以调节其在血小板聚集中的活性。ADAMTS 13缺乏导致血栓性血小板减少性紫癜（TTP）。本研究的目的是通过对ADAMTS 13的基础分析，产生临床有用的成果。[ADAMTS 13缺陷型小鼠的分析]制作Adamts 13基因缺陷型小鼠。他们表现出血栓前状态，但没有自发性血小板减少症、溶血性贫血和微血管血栓形成的症状。这表明小鼠中ADAMTS 13的完全缺乏不足以引起TTP，并且除了ADAMTS 13缺乏之外的其他因素可能是TTP发展所必需的。[携带截短型ADAMTS 13的同源小鼠的产生和分析]我们先前鉴定了两种小鼠ADAMTS 13：具有与人ADAMTS 13相同的结构域的129/Sv株ADAMTS 13和缺乏C末端多结构域的C57 BL/6株ADAMTS 13。为了评估这些结构域在体内的意义，我们产生并分析了129只携带C57 BL/6型ADAMTS 13的/SV遗传背景同源小鼠。【生化及流行病学分析】采用荧光法分析ADAMTS 13的生化特征。在日本人群中经常观察到的ADAMTS 13的P475 S形式显示出野生型约70%的活性。【ADAMTS 13相互作用蛋白质的研究】我们使用酵母双杂交系统鉴定了ADAMTS 13相互作用蛋白质的候选物，其中一个被证实与ADAMTS 13直接结合。本研究为ADAMTS 13基因的翻译研究提供了新的信息。

Plasma ADAMTS13 cleaves von Willebrand factor (VWF) multimers to regulate their activity in platelet aggregation. ADAMTS13 deficiency results in thrombotic thrombocytopenic purpura (TTP). The aim of this research is the production of clinically useful achievement through the basic analysis of ADAMTS13. [Analysis of ADAMTS13-deficient mice] Mice lacking the Adamts13 gene were generated. They showed a prothrombotic state but no symptoms of spontaneous thrombocytopenia, hemolytic anemia, and microvascular thrombosis. This suggested that a complete lack of ADAMTS13 in mice was not sufficient to cause TTP and other factors in addition to ADAMTS13 deficiency may be necessary for development of TTP. [Generation and analysis of congenic mice carrying truncated ADAMTS13] We previously identified two kinds of mouse ADAMTS13:129/Sv-strain ADAMTS13 with the same domains as human ADAMTS13 and C57BL/6-strain ADAMTS13 lacking the C-terminal multiple domains. To assess the significance of these domains in vivo, we generated and analyzed 129/Sv-genetic-background congenic mice that carry the C57BL/6-type ADAMTS13. [Biochemical and epidemiological analysis] Using a fluorescence-based assay, the biochemical features of ADAMTS13 were analyzed. The P475S form of ADAMTS13, frequently observed in the Japanese population, showed an approximately 70% activity of the wild type. [Search of ADAMTS13-interacting proteins] We used a yeast two-hybrid system to identify the candidates of ADAMTS13-interacting proteins, one of which was confirmed to bind directly to ADAMTS13. The present study provided new information about ADAMTS13, which will be useful for oncoming translational research.