Cytoskeletal Membrane Dynamics - Mark A. McNiven

Mx proteins are induced by type I interferon and inhibit a broad range of viruses by undefined mechanisms. They are included within the dynamin family of large GTPases, which are involved in vesicle trafficking and share common biophysical features. These properties include the propensity to self assemble, an affinity for lipids, and the ability to tubulate membranes. We establish that human MxA, despite sharing only 30% homology with conventional dynamin, possesses many of these properties. We demonstrate for the first time that MxA self-assembles into rings, can tubulate lipids in vitro, and associates with a specific membrane compartment in cells, the smooth ER.

J Biol Chem 2002 Jun 14;277(24):21829-35
The antiviral dynamin family member, MxA, tubulates lipids and localizes to the smooth endoplasmic reticulum.
Accola MA, Huang B, Al Masri A, McNiven MA.

MxA remodels spherical phosphotidylserine liposomes into tubules. The liposomes are deformed into branched tubules upon addition of (His)6-tagged MxA and GTP. Higher magnification reveals striations along tubulated liposomes (arrows).

MxA colocalizes with a smooth ER marker.
a and b, Hep3B cells were treated with IFN b and prepared for indirect immunofluorescence to detect MxA (a and b) and AMF-R (a' and b'). Extensive co-localization is evident in a'', b''. Scale bar in a and b insets represent 10 mm.

MxA Contact Information
The Mx projects have been mainly driven by Drs. Ahmad Abdulkarim and Molly Accola. If you would like any additional information, please contact Dr. Abdulkarim.