Dynamics of cell membranes and the underlying cytoskeletons observed by noninterferometric widefield optical profilometry and fluorescence microscopy.
Combining the noninterferometric wide-field optical profilometry technique with fluorescence microscopy, we observe the membrane activities of a living cell as well as the structures of its cytoskeletons. The membrane ripples of a lamellipodium are related to similar structures of the underlying actin filaments. However, we find the ripples appear prior to and disappear later than the corresponding actin filament structures, which supports the elastic Brownian ratchet model of cell motility. In addition, we measure the three-dimensional movement of a fibronectin-coated latex bead on the membrane. The bead motion is determined by the movement and branching of the actin molecules on the filament, as well as by the displacement of the filament itself.
Wang
Chun-Chieh
CC
Graduate Institute of Physics, National Chung Cheng University, Chia-Yi, Taiwan.
Lin
Jiunn-Yuan
JY
Chen
Hsiao-Chao
HC
Lee
Chau-Hwang
CH
D016475:3T3 Cells; D000818:Animals; D002462:Cell Membrane / Q000502:physiology / Q000648:ultrastructure*; D002465:Cell Movement / Q000502:physiology*; D003599:Cytoskeleton / Q000502:physiology / Q000648:ultrastructure*; D007368:Interferometry; D008560:Membrane Fluidity / Q000502:physiology*; D051379:Mice; D008856:Microscopy, Fluorescence / Q000379:methods*; D010783:Photometry / Q000379:methods*; D013499:Surface Properties