Conformational dynamics of dynamin-like MxA revealed by single-molecule FRET
Chen, Y., Zhang, L., Graf, L., Yu, B., Liu, Y., Kochs, G., Zhao, Y., Gao, S.(2017) Nat Commun 8: 15744-15744
- PubMed: 28548099 
- DOI: https://doi.org/10.1038/ncomms15744
- Primary Citation of Related Structures:  
5GTM - PubMed Abstract: 
Human myxovirus resistance protein 1 (MxA) restricts a wide range of viruses and is closely related to the membrane-remodelling GTPase dynamin. The functions of MxA rely on domain rearrangements coupled with GTP hydrolysis cycles. To gain insight into this process, we studied real-time domain dynamics of MxA by single-molecule fluorescence resonance energy transfer. We find that the GTPase domain-bundle-signalling-element (BSE) region can adopt either an 'open' or a 'closed' conformation in all nucleotide-loading conditions. Whereas the open conformation is preferred in nucleotide-free, GDP·AlF 4 - -bound and GDP-bound forms, loading of GTP activates the relative movement between the two domains and alters the conformational preference to the 'closed' state. Moreover, frequent relative movement was observed between BSE and stalk via hinge 1. On the basis of these results, we suggest how MxA molecules within a helical polymer collectively generate a stable torque through random GTP hydrolysis cycles. Our study provides mechanistic insights into fundamental cellular events such as viral resistance and endocytosis.
Organizational Affiliation: 
State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou 510060, China.