Investigation of the unique character of the squid novel neutral metalloprotease

只有鱿鱼肌肉中存在的在中性条件下具有活性的金属蛋白酶。这种中性金属蛋白酶对肌球蛋白具有很高的活性，被认为是与肌肉蛋白质代谢有关的酶。然而，虽然在鱿鱼总科的肌肉中可以接受活动，但在乌贼总科的肌肉中并没有活动。此外，除了直线蛋白代谢外，还有什么功能在其中，因为活性很高，只有极少数的肝脏有肌球蛋白的量。该酶存在肌球蛋白分解部位不同的三种亚型。为了明确该新型蛋白水解酶的功能，尝试了用聚合酶链式反应的方法测定所有碱基的排列。当氨基酸排列假定为碱基排列时，鱿鱼和鱼叉鱿鱼的异构体存在方式不同。对任何一种异构体都有一个前结构域的前体结构进行了分析，结果表明它是一种分泌性的带有信号肽的蛋白酶。从碱基排列可以清楚地表明，它再次属于一个阿司匹林家族。存在与消化酶的调节和生长因子的生成等有关的东西，属于ASTIN家族的蛋白酶。当研究一个蛋白酶域的系统发育树时，也发现一个鱿鱼的蛋白水解酶并不属于通常所知的ASTIN家族的簇。该鱿鱼的新的蛋白水解酶虽然在命名之前是肌球蛋白酶，但它与类ASTIN的鱿鱼金属蛋白水解酶发生了变化。

The metallprotease which has activity in the neutral found out by only the squid muscle exists. This neutral metallprotease shows high activity to myosin, and was considered to be the enzyme related to the metabolism of muscular protein. However, although activity was accepted in TEUTHOIDEA squid muscles, such as a squid, was not activity in the muscles of SEPIOIDEA. Furthermore, what has functions other than line protein metabolism in it since activity is high to the very few liver of the amount of myosin was conjectured. Three kinds of isoform from which the decomposition position of myosin differs existed in this enzyme. To clear the function of this novel protease, the determination of all base arrangement was tried by the PCR method. When amino acid arrangement was presumed base arrangement, it turns out by the squid and the spear squid that the methods of the existence of isoform differ. The precursor structure where any isoform had a pro-domain was taken, and it became clear that it is protease of secretion nature with signal peptide. It was able to be shown clearly from base arrangement that it belongs to an astacin family again. The thing in connection with as digestive enzyme regulation and generating of a growth factor in the protease belonging to an astacin family etc. exists. When the phylogenetic tree of a protease domain was investigated, it also turns out that the protease of a squid does not belong to the cluster of which astacin family known conventionally. Although the novel protease of this squid was before named myosinase, it changed with astacin-like squid metalloprotease.