Measuring the elasticity of clathrin-coated vesicles via atomic force microscopy.
Using a new scheme based on atomic force microscopy (AFM), we investigate mechanical properties of clathrin-coated vesicles (CCVs). CCVs are multicomponent protein and lipid complexes of approximately 100 nm diameter that are implicated in many essential cell-trafficking processes. Our AFM imaging resolves clathrin lattice polygons and provides height deformation in quantitative response to AFM-substrate compression force. We model CCVs as multilayered elastic spherical shells and, from AFM measurements, estimate their bending rigidity to be 285 +/- 30 k(B)T, i.e., approximately 20 times that of either the outer clathrin cage or inner vesicle membrane. Further analysis reveals a flexible coupling between the clathrin coat and the membrane, a structural property whose modulation may affect vesicle biogenesis and cellular function.
Division of Bioengineering and Physical Science, Office of Research Services, Office of the Director, National Institutes of Health, Bethesda, Maryland, USA.
Albert J
AJ
Jin
Kondury
K
Prasad
Paul D
PD
Smith
Eileen M
EM
Lafer
Ralph
R
Nossal
D022163:Clathrin-Coated Vesicles / Q000737:chemistry / Q000648:ultrastructure*; D004548:Elasticity; D018625:Microscopy, Atomic Force; D008954:Models, Biological