Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), Lausanne, Switzerland.
Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
Proteins. 2021 Feb;89(2):251-255. doi: 10.1002/prot.26005. Epub 2020 Sep 25.
The Rad50-Mre11 nuclease complex plays a vital role in DNA repair in all domains of life. It recognizes and processes DNA double-strand breaks. Rad50 proteins fold into an extended structure with a 20 to 60 nm long coiled coil connecting a globular ABC ATPase domain with a zinc hook dimerization domain. A published structure of an archaeal Rad50 zinc hook shows coiled coils pointing away from each other. Here we present the crystal structure of an alternate conformation displaying co-aligned coiled coils. Archaeal Rad50 may thus switch between rod-shaped and ring-like conformations as recently proposed for a bacterial homolog.
Rad50-Mre11 核酸酶复合物在所有生命领域的 DNA 修复中起着至关重要的作用。它识别和处理 DNA 双链断裂。Rad50 蛋白折叠成一种延伸结构，其中 20 到 60nm 长的螺旋线圈连接球形 ABC ATP 酶结构域和锌钩二聚化结构域。已发表的古菌 Rad50 锌钩结构显示螺旋线圈彼此远离。在这里，我们展示了一种替代构象的晶体结构，显示出共对齐的螺旋线圈。最近有研究表明，细菌同源物可能会在棒状和环状构象之间切换，古菌 Rad50 也是如此。
