Molecular basis of protein cross-linking reactions for cellular functions

转氨酶是通过肽结合的谷氨酰胺残基催化蛋白质交联或修饰的酶。这些反应对于血液凝固、皮肤表皮形成和细胞凋亡等多种生物学过程是必不可少的。为了阐明其在哺乳动物中的生理作用和表达位点，我们利用近年来获得的高活性底物肽，分析了其表达模式，并建立了可能底物的鉴定系统。在研究中，RNA，蛋白质（使用抗体）的表达，原位酶活性进行了研究。此外，尝试建立FRET系统来检测细胞内活性。结果表明，体外培养系统是成功的。此外，以青鳉为模式动物，分析了青鳉转氨酶的直向同源物：获得了生化数据，并建立了一对遗传缺失鱼。

Transglutaminases are the enzymes that catalyze protein cross-linking or modification via peptide-bound glutamine residues. These reactions are essential for the multiple biological processes such as blood coagulation, skin epidermis formation and apoptosis. In order to elucidate the physiological roles and expression sites on mammals, using highly reactive substrate peptides (obtained by us for these years), we analyzed expression pattern and established identification system of possible substrates. In the studies, expressions for RNA, protein (using antibody), in situ enzymatic activity were investigated. Furthermore, establishment of FRET system to detect intracellular activity was attempted. As a result, in vitro system was successful. In addition, Medaka (Oryzias latepis) as a model animal, was analyzed for the orthologues of transglutaminases: biochemical data and establishment of a couple of genetic loss fish was produced.