TY - JOUR
T1 - Coupled myosin VI motors facilitate unidirectional movement on an F-actin network
AU - Sivaramakrishnan, Sivaraj
AU - Spudich, James A.
PY - 2009/10/5
Y1 - 2009/10/5
N2 - Unconventional myosins interact with the dense cortical actin network during processes such as membrane trafficking, cell migration, and mechanotransduction. Our understanding of unconventional myosin function is derived largely from assays that examine the interaction of a single myosin with a single actin filament. In this study, we have developed a model system to study the interaction between multiple tethered unconventional myosins and a model F-actin cortex, namely the lamellipodium of a migrating fish epidermal keratocyte. Using myosin VI, which moves toward the pointed end of actin filaments, we directly determine the polarity of the extracted keratocyte lamellipodium from the cell periphery to the cell nucleus. We use a combination of experimentation and simulation to demonstrate that multiple myosin VI molecules can coordinate to efficiently transport vesiclesize cargo over 10 μm of the dense interlaced actin network. Furthermore, several molecules of monomeric myosin VI, which are nonprocessive in single molecule assays, can coordinate to transport cargo with similar speeds as dimers.
AB - Unconventional myosins interact with the dense cortical actin network during processes such as membrane trafficking, cell migration, and mechanotransduction. Our understanding of unconventional myosin function is derived largely from assays that examine the interaction of a single myosin with a single actin filament. In this study, we have developed a model system to study the interaction between multiple tethered unconventional myosins and a model F-actin cortex, namely the lamellipodium of a migrating fish epidermal keratocyte. Using myosin VI, which moves toward the pointed end of actin filaments, we directly determine the polarity of the extracted keratocyte lamellipodium from the cell periphery to the cell nucleus. We use a combination of experimentation and simulation to demonstrate that multiple myosin VI molecules can coordinate to efficiently transport vesiclesize cargo over 10 μm of the dense interlaced actin network. Furthermore, several molecules of monomeric myosin VI, which are nonprocessive in single molecule assays, can coordinate to transport cargo with similar speeds as dimers.
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U2 - 10.1083/jcb.200906133
DO - 10.1083/jcb.200906133
M3 - Article
C2 - 19786577
AN - SCOPUS:70449721124
SN - 0021-9525
VL - 187
SP - 53
EP - 60
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 1
ER -