A hand-over-hand diffusing model for myosin-VI molecular motors.
Single molecules of dimeric myosin-VI have been demonstrated to be able to move processively towards the pointed end of actin filament with a mean step size of approximately 36 nm. Here we present a hand-over-hand diffusing mechanism for this unidirectional movement. Based on this mechanism, its dynamical behaviors such as the step-size distribution, dwell-time distributions and mean dwell time at various ATP and ADP concentrations and under various loads are studied in detail. The calculated results show good agreement with previous experimental results. The processive movement of mutant myosin-V with its neck domains truncated to only one IQ motif can also be explained by using this hand-over-hand diffusing model.
Xie
Ping
P
Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China. pxie@aphy.iphy.ac.cn
Dou
Shuo-Xing
SX
Wang
Peng-Ye
PY
D000199:Actins / Q000737:chemistry; D000244:Adenosine Diphosphate / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D004058:Diffusion; D008956:Models, Chemical; D020409:Molecular Motor Proteins / Q000737:chemistry*; D018995:Myosin Heavy Chains / Q000737:chemistry*
D000199:Actins; D020409:Molecular Motor Proteins; C089785:myosin VI; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D018995:Myosin Heavy Chains