What is the function of kinesin-5 in mitotic spindle dynamics?
Mitotic spindle bipolarity depends on antagonistic motor force balance between outward pushing and inward pulling motors establishing steady state length and facilitating chromosome bi orientation. Kinesin-5 family member Eg5 KSP is homotetrameric motor formed by antiparallel dimerization of dimers through centrally located tetramerization domain placing two motor heads at each end of dumbbell shape about 80 nm long. This geometry enables simultaneous crosslinking of antiparallel interpolar microtubules emerging from opposite poles and walking toward plus ends of each at about 20 nm per second
Ref: Wittmann et al., Nat Cell Biol 2001 – Kinesin-5 function bipolar sliding of antiparallel microtubules.