Fluctuation analysis of myosin-coated bead movement along actin bundles of Nitella.
Movements of myosin-coated magnetic beads on the actin bundles of Nitella axilliformis were studied using fluctuation analysis. Regulated force applied by magnetic field could hold magnetic beads stationary against their driving force. Thus beads selected by the same magnetic force had almost the same number of active motor proteins. When the magnetic field was switched off, the beads began sliding again and reached a steady sliding velocity. The fluctuations of bead movements were estimated from the deviations of displacement and those of velocity. The results indicate that (1) the mean step-size was 6.8 nm, and (2) the equivalent stiffness of motor proteins increased during the steady sliding compared with the stationary state.
Yamasaki
H
H
Communications Research Laboratory, Kansai Advanced Research Center, Kobe, Japan. yamas@crl.go.jp
Nakayama
H
H
D000199:Actins / Q000737:chemistry*; D001696:Biomechanical Phenomena; D000460:Chlorophyta / Q000737:chemistry*; D009218:Myosins / Q000737:chemistry*
D000199:Actins; D009218:Myosins