4P4S

GMPPCP-bound stalkless-MxA

Summary for 4P4S

• Entry DOI: 10.2210/pdb4p4s/pdb
• Descriptor: Interferon-induced GTP-binding protein Mx1, PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER, MAGNESIUM ION, ... (5 entities in total)
• Functional Keywords: gtpase, dynamin-related protein, antiviral, signaling protein, antiviral protein-hydrolase complex, antiviral protein/hydrolase
• Biological source: Homo sapiens (Human); More
• Cellular location: Cytoplasm . Isoform 2: Cytoplasm : P20591 P20591
• Total number of polymer chains: 2
• Total formula weight: 72230.92

Authors

Rennie, M.L.,McKelvie, S.A.,Bulloch, E.M.,Kingston, R.L. (deposition date: 2014-03-13, release date: 2014-10-22, Last modification date: 2024-10-09)

Primary citation

Rennie, M.L.,McKelvie, S.A.,Bulloch, E.M.,Kingston, R.L.
Transient Dimerization of Human MxA Promotes GTP Hydrolysis, Resulting in a Mechanical Power Stroke.
Structure, 22:1433-1445, 2014

PubMed Abstract: Myxovirus resistance (Mx) proteins restrict replication of numerous viruses. They are closely related to membrane-remodeling fission GTPases, such as dynamin. Mx proteins can tubulate lipids and form rings or filaments that may interact directly with viral structures. GTPase domain dimerization is thought to allow crosstalk between the rungs of a tubular or helical assembly, facilitating constriction. We demonstrate that the GTPase domain of MxA dimerizes to facilitate catalysis, in a fashion analogous to dynamin. GTP binding is associated with the lever-like movement of structures adjacent to the GTPase domain, while GTP hydrolysis returns MxA to its resting state. Dimerization is not significantly promoted by substrate binding and occurs only transiently, yet is central to catalytic efficiency. Therefore, we suggest dimerization functions to coordinate the activity of spatially adjacent Mx molecules within an assembly, allowing their mechanical power strokes to be synchronized at key points in the contractile cycle.

PubMed: 25295396
DOI: 10.1016/j.str.2014.08.015

Experimental method

X-RAY DIFFRACTION (3.3 Å)