Remote control of microtubule plus-end behavior from the minus-end
Many cellular processes rely on specifying the function of individual microtubule filaments. The Barral group (IBC) shows in ‘eLIFE’ that microtubule organizing centers use a motor protein to communicate with the distal end of their associated microtubules and remotely control their behavior.
In cells, proper function of the microtubule cytoskeleton requires that specific roles are assigned to individual microtubules but we know little about how microtubules become differentiated from each other. The Barral (ETH), Stelling (ETH) and Steinmetz (PSI) groups show that yeast centrosomes (or spindle pole bodies - SPBs) differently control the plus-end dynamics and function of their astral microtubules, remotely from the minus-end. Specifically, old SPBs recruit the kinesin motor protein Kip2, which then walks to the plus-end of the emanating microtubules and promotes their growth. Kip2 recruitment at the SPB depends on dedicated proteins on the old SPB. Phosphorylation of Kip2 prevents random lattice binding. Releasing Kip2 from these controls equalizes its distribution, the length of microtubules and the delivery of its cargos between the two spindle sides. These observations reveal that microtubule organizing centers remotely control and specify microtubule function.
Link to the publication in external page eLIFE