Download MendeleyNear-Atomic Resolution Structure Determination of a Cypovirus Capsid and Polymerase Complex Using Cryo-EM at 200kV
Li, X., Zhou, N., Chen, W., Zhu, B., Wang, X., Xu, B., Wang, J., Liu, H., Cheng, L.(2017) J Mol Biol 429: 79-87
- PubMed: 27914893
- DOI: https://doi.org/10.1016/j.jmb.2016.11.025
- Primary Citation of Related Structures:
5H0R, 5H0S - PubMed Abstract:
Single-particle cryo-electron microscopy (cryo-EM) allows the high-resolution structural determination of biological assemblies in a near-native environment. However, all high-resolution (better than 3.5Å) cryo-EM structures reported to date were obtained by using 300kV transmission electron microscopes (TEMs). We report here the structures of a cypovirus capsid of 750-Å diameter at 3.3-Å resolution and of RNA-dependent RNA polymerase (RdRp) complexes within the capsid at 3.9-Å resolution using a 200-kV TEM. The newly resolved structure revealed conformational changes of two subdomains in the RdRp. These conformational changes, which were involved in RdRp's switch from non-transcribing to transcribing mode, suggest that the RdRp may facilitate the unwinding of genomic double-stranded RNA. The possibility of 3-Å resolution structural determinations for biological assemblies of relatively small sizes using cryo-EM at 200kV was discussed.
Organizational Affiliation:
College of Physics and Information Science, Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha, Hunan, 410081, China; Technology Center for Protein Sciences, Tsinghua University, Beijing, 100084, China.
