[Actin polymerization machinery in live cells as revealed by single-molecule imaging].
Actin polymerization generates force to drive cell edge protrusion, and plays an important role in migration and shape change of cells. Many molecular mechanisms regulating actin dynamics have been identified, but probing their individual roles within the cells becomes increasingly difficult because of their complex interactions. Here we describe our invention of single-molecule visualization of fluorescently-labeled actin and its related molecules that has revealed dynamic nature of the actin arrays in live cells. Single-molecule observation enabled us to visualize the position and the duration of assembly of actin filaments and actin-related molecules. Moreover, this imaging method led us to discover processive actin-capping motion of a formin-related protein, mDial. Our approach of single-molecule imaging will be instrumental to quantitative analysis of cell signaling.
Tsuji
Takahiro
T
Department of Pharmacology, Kyoto University Faculty of Medicine.
Watanabe
Naoki
N
D000199:Actins / Q000502:physiology*; D002468:Cell Physiological Phenomena; D003952:Diagnostic Imaging / Q000379:methods*; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D011108:Polymers
D000199:Actins; D011108:Polymers