Sugita H, Shishikura F
Institute of Biological Sciences, University of Tsukuba, Ibaraki, Japan.
Zoolog Sci. 1995 Oct;12(5):661-7. doi: 10.2108/zsj.12.661.
About 83% of the amino acid sequence of hemocyanin subunit HR6 from the Southeast Asian horseshoe crab, Carcinoscorpius rotundicauda, has been determined. There is a difference of about 43% between HR6 and complete sequences of chelicerate hemocyanin subunits from the American horseshoe crab, Limulus polyphemus, and a tarantula, Eurypelma californicum. However, the immunologically identical subunits HR6 and HT6 from Tachypleus tridentatus (Japanese horseshoe crab) show 2.7% sequence difference. Based on the amino acid sequences of HR6 and HT6, the divergence between C. rotundicauda and T. tridentatus occurred about 9.6 million years ago. In the case of horseshoe crab hemocyanin subunits, it seems that the orthologous homologues in many homologous subunits between species are immunologically detectable.
已确定来自东南亚鲎（圆尾鲎）血蓝蛋白亚基HR6约83%的氨基酸序列。来自美国鲎（美洲鲎）和一只狼蛛（加利福尼亚食鸟蛛）的螯肢动物血蓝蛋白亚基的完整序列与HR6之间存在约43%的差异。然而，来自三刺鲎（日本鲎）的免疫相同亚基HR6和HT6显示出2.7%的序列差异。根据HR6和HT6的氨基酸序列，圆尾鲎和三刺鲎之间的分化发生在约960万年前。就鲎血蓝蛋白亚基而言，物种间许多同源亚基中的直系同源物似乎在免疫上是可检测的。
