Kinesin

Kinesin is a motor that carries cargo along microtubule tracks. In a nerve cell it pulls cargo outward, away from the cell body. Toward which end of the microtubule does it walk?

Each kinesin step moves the cargo about 8 nm, the length of one building block of the microtubule track. What does each step cost the motor?

A single kinesin does not walk forever. After a while it lets go of the microtubule. About how many steps does it take before it falls off?

Kinesin walks on microtubules and myosin walks on actin, and their protein sequences are almost unrelated. What do their motor cores still share?

When ATP binds the front head, a short strand zips onto it and points forward, so the free head lands ahead. But this zipping is no leg muscle. What actually carries the free head to its next site?

A nerve cell can run about a metre, from your spine to your foot, and its proteins are made near the spine. If those proteins only drifted, roughly how long would the trip take?

One kinesin lets go after about a micrometre, but a nerve cell can be a metre long. How does the cargo still reach the far end?

Cargo bubbles in a nerve cell carry more than one kind of motor. Kinesin pulls them outward. Which motor on the same tracks pulls the other way, back toward the cell body?

Long nerve cells depend on kinesin to keep their far ends supplied. What kind of illness can a mutation in a nerve kinesin gene cause?

Kinesin has two identical heads. Scientists put a dye on just one head and watched it walk. The dye jumped about 17 nm, then stayed still for a step, then jumped again. What does that show about how kinesin walks?