10月16日，日本一研究小组在15日的《欧洲分子生物学组织通讯》网络版上发表论文说，他们破解了对生殖细胞形成具有重要作用的一种蛋白质结构。
“Nanos”是众多动物形成生殖细胞所必需的蛋白质，这种蛋白质一旦出现异常就会导致不孕，因此对其结构的成功破解有助于探究不孕症的原因。
横滨市立大学和三重大学联合研究小组通过技术手段，使鲤科斑马鱼的“Nanos”蛋白质在大肠杆菌中大量表达，然后提炼出该蛋白质并使其结晶。之后，研究人员利用高强度X射线设备成功对该蛋白质的结构进行了分析。结果发现，“Nanos”的结构不同于已知的任何一种蛋白质。
参与这项研究的桥本博表示，对“Nanos”的研究有望获得飞跃性进展，希望成果能够帮助解开生殖细胞形成的具体机制。
英文摘要：
EMBO doi:10.1038/embor.2010.155
Crystal structure of zinc-finger domain of Nanos and its functional implications
Hiroshi Hashimoto1, Kodai Hara1,*,?, Asami Hishiki1,*, Shigeta Kawaguchi1, Naoki Shichijo1, Keishi Nakamura2, Satoru Unzai1, Yutaka Tamaru2, Toshiyuki Shimizu3 " Mamoru Sato1
1 Graduate School of Nanobioscience, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
2 Graduate School of Bioresources, Mie University, 1577 Kurimamachiya, Tsu, Mie 514-8507, Japan
3 Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Nanos is an RNA-binding protein that is involved in the development and maintenance of germ cells. In combination with Pumilio, Nanos binds to the 3′ untranslated region of a messenger RNA and represses its translation. Nanos has two conserved Cys-Cys-His-Cys zinc-finger motifs that are indispensable for its function. In this study, we have determined the crystal structure of the zinc-finger domain of zebrafish Nanos, for the first time revealing that Nanos adopts a novel zinc-finger structure. In addition, Nanos has a conserved basic surface that is directly involved in RNA binding. Our results provide the structural basis for further studies to clarify Nanos function.
