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Biophysics of Proteins at Surfaces: Assembly, Activation, Signaling
Thursday Speaker Abstracts
High-speed Atomic Force Microscopy: The Dynamics and Interaction of Protein and
Membrane Surfaces
Simon Scheuring
, Lorena Redondo, Atsushi Miyagi, Felix Rico, Ignacio Casuso.
INSERM / Aix-Marseille University, Marseille, France.
The advent of high-speed atomic force microscopy (HS-AFM; [1]) has opened a novel research
field for the dynamic analysis of single bio-molecules [2,3,4,5]. The endosomal sorting complex
required for transport (ESCRT) mediates membrane remodeling in cells. We used HS-AFM to
study the ESCRT-III complex, i.e. Snf7. HS-AFM movies reveal Snf7 complex formation from
filaments to maturated assemblies: Interfilament dynamics provide basis for a mechanistic
understanding of tension generation for membrane fission [6]. Annexin-V (A5) binds to
negatively charged lipid bilayers in the presence of Ca2+ for membrane healing. Using a HS-
AFM coupled to a buffer exchange flow system, we found two classes with different apparent
affinity in the reversible association-dissociation of A5 to the membrane [7].
[1] T. Ando, et al., Proceedings of the National Academy of Sciences 98, 12468 (2001)
[2] I. Casuso, et al., Nature Nanotechnology, 7, 525 (2012)
[3] A. Colom, et al., Journal of Molecular Biology, 423, 249 (2012)
[4] A. Colom, et al., Nature Communications, DOI:10.1038/ncomms3155 (2013)
[5] F. Rico, et al., Science, 342, 741 (2013)
[6] N. Chiaruttini, et al., in press (2015)
[7] A. Miyagi, et al., submitted (2015)