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Myosin Action Versus Kinesin

Myosin action differs from that of kinesin in that one of the kinesin heads is always in contact with a microtubule, whereas both myosin heads become completely detached from the actin filament. How are these differences correlated with the two types of motor activities in which these proteins engage?

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I'm going to rephrase the statement somewhat

Kinesin is always on the microtubule.

Myosin becomes completely detached from the actin filament.

Correlate the differences with the motor activities of each.

Essentially, myosin moves along the f-actin filament and kinesin (and dynein) move along microtubules. Both involve the movement along the track with repeated cycles of domain specific attachment(s), force generation, detachment and ATP hydrolysis. They have similar structures and catalytic capacities for ATP-processing as can be seen from the attached word documents that show the structures. The myosin head domain and the kinesin motor domain are similar in the underlying protein fold of their myosin and kinesin motor domains.

Myosin is involved in muscle contraction, its detachment does not necessarily involve a large distance of separation from the ...