Laboratory of Aquatic Molecular Biology and Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
Comp Biochem Physiol Part D Genomics Proteomics. 2006 Mar;1(1):28-34. doi: 10.1016/j.cbd.2005.12.001. Epub 2006 Feb 2.
Myosin is a highly conserved, ubiquitous actin-based molecular motor that is distributed as diverse as from prokaryotes to mammalian tissues. Among various types in the myosin family proteins, class II, also called sarcomeric, myosin is a classical, conventional molecule that has been extensively studies on its functional and structural properties. It consists of two heavy chains (MYH) of about 200 kDa and four light chains of about 20 kDa. The exon-intron organization was determined for the major subunit of MYH, which contains ATP-hydrolysis and actin-binding sites, from torafugu (tiger pufferfish) Takifugu rubripes fast skeletal muscles. Comprehensive investigation for fast skeletal MYHs based on the fugu (torafugu) genome database and subsequent construction of their physical map revealed that torafugu contains at least 8 putative skeletal MYHs. Furthermore, genomic structural analysis revealed that skeletal MYHs are not clustered in a single locus, but rather spread to at least four loci, with two of them locating at the mammalian syntenic regions. Such arrangement of torafugu MYHs are in a marked contrast to mammalian fast skeletal MYHs that are clustered in a single locus. These data suggest that an ancient segmental duplication or whole-genome duplication occurred in fish lineage as in many other reported torafugu genes.
肌球蛋白是一种高度保守、普遍存在的肌动蛋白依赖的分子马达，分布广泛，从原核生物到哺乳动物组织都有。在肌球蛋白家族蛋白的各种类型中，II 类，也称为肌节肌球蛋白，是一种经典的常规分子，其功能和结构特性已经得到了广泛的研究。它由两个大约 200kDa 的重链（MYH）和四个大约 20kDa 的轻链组成。从虎斑河豚（Takifugu rubripes）快速骨骼肌中确定了包含 ATP 水解和肌动蛋白结合位点的 MYH 主要亚基的外显子-内含子组织，对快速骨骼肌 MYHs 进行了全面研究，基于 fugu（torafugu）基因组数据库，随后构建了它们的物理图谱，发现 torafugu 至少含有 8 种假定的骨骼肌 MYHs。此外，基因组结构分析表明，骨骼肌 MYHs 没有聚集在一个单一的基因座，而是分布在至少四个基因座，其中两个位于哺乳动物同源区域。torafugu MYHs 的这种排列与哺乳动物快速骨骼肌 MYHs 形成鲜明对比，后者聚集在一个单一的基因座中。这些数据表明，鱼类谱系中发生了古老的片段重复或全基因组重复，就像许多其他报道的 torafugu 基因一样。
