The Crystal Structure of the Drosophila Germline Inducer Oskar Identifies Two Domains with Distinct Vasa Helicase- and RNA-Binding Activities
The Crystal Structure of the Drosophila Germline Inducer Oskar Identifies Two Domains with Distinct Vasa Helicase- and RNA-Binding Activities
复制标题
果蝇种系诱导剂 Oskar 的晶体结构确定了具有不同 Vasa 螺旋酶和 RNA 结合活性的两个结构域
DOI：
10.1016/j.celrep.2015.06.055
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发表时间：
2015-07-28
期刊：
影响因子：
8.8
通讯作者：
Ephrussi, Anne
中科院分区：
文献类型：
--
作者：
Jeske, Mandy;Bordi, Matteo;Ephrussi, Anne
在许多动物中，在早期发育过程中，种质将生殖系与索马分离。Oskar蛋白以其诱导果蝇生殖质形成和生殖细胞的能力而闻名。然而，种质形成的分子基础仍不清楚。在这里，我们表明，奥斯卡是一种RNA结合蛋白在体内，交联纳米，极性颗粒成分，和生殖细胞少的mRNA，其中每一个都有一个在种系形成的作用。此外，我们提出了高分辨率的晶体结构的两个奥斯卡域。RNA结合在体外映射到C-末端结构域，其显示与SGNH水解酶的结构相似性。高度保守的N-末端LOTUS结构域形成二聚体，并在体外介导Oskar与种系特异性RNA解旋酶Vasa的相互作用。我们的研究结果表明Oskar在RNA和Vasa结合中具有双重功能，为其种质功能提供了分子线索。
In many animals, the germ plasm segregates germline from soma during early development. Oskar protein is known for its ability to induce germ plasm formation and germ cells in Drosophila. However, the molecular basis of germ plasm formation remains unclear. Here, we show that Oskar is an RNA-binding protein in vivo, crosslinking to nanos, polar granule component, and germ cell-less mRNAs, each of which has a role in germline formation. Furthermore, we present high-resolution crystal structures of the two Oskar domains. RNA-binding maps in vitro to the C-terminal domain, which shows structural similarity to SGNH hydrolases. The highly conserved N-terminal LOTUS domain forms dimers and mediates Oskar interaction with the germline-specific RNA helicase Vasa in vitro. Our findings suggest a dual function of Oskar in RNA and Vasa binding, providing molecular clues to its germ plasm function.