Sasaki T, Yoshimura N, Kikuchi T, Hatanaka M, Kitahara A, Sakihama T, Murachi T
J Biochem. 1983 Dec;94(6):2055-61. doi: 10.1093/oxfordjournals.jbchem.a134561.
The structural relationship between calpain I (low Ca2+-requiring) and calpain II (high Ca2+-requiring) molecules and their respective larger (80K) and smaller (30K) subunit proteins of several non-muscular tissues and cells was studied by testing immunological cross-reactivities. In addition to qualitative analyses by a conventional double immunodiffusion method, quantitative data were obtained, for the first time, by enzyme-linked immunosorbent assays using affinity-purified anticalpain I and anti-calpain II immunoglobulins. The enzyme sources included rat kidney, porcine kidney and erythrocytes, and human erythrocytes. It was concluded that the 30K subunits are immunologically almost indistinguishable between calpains, either I or II, not only from the same but also from different sources, while the 80K subunits of different origins are immunologically related to variable extents but always with discrimination between calpain I and calpain II. Similarity of the 30K subunit proteins and dissimilarity of the 80K counterparts were further substantiated by their chromatographic and electrophoretic behaviors.
通过检测免疫交叉反应性，研究了钙蛋白酶I（低钙需求型）和钙蛋白酶II（高钙需求型）分子之间的结构关系，以及它们在几种非肌肉组织和细胞中各自较大的（80K）和较小的（30K）亚基蛋白。除了通过传统的双向免疫扩散法进行定性分析外，首次使用亲和纯化的抗钙蛋白酶I和抗钙蛋白酶II免疫球蛋白，通过酶联免疫吸附测定获得了定量数据。酶来源包括大鼠肾脏、猪肾脏和红细胞，以及人类红细胞。得出的结论是，30K亚基在免疫上几乎无法区分钙蛋白酶I或II，不仅来自相同来源，也来自不同来源，而不同来源的80K亚基在免疫上有不同程度的相关性，但钙蛋白酶I和钙蛋白酶II之间总是有区别。30K亚基蛋白的相似性和80K对应物的不同性通过它们的色谱和电泳行为得到了进一步证实。
