Dynein‐dependent transport of spindle assembly checkpoint proteins off kinetochores toward spindle poles

摘要

Apredominantmechanismofspindleassemblycheckpoint(SAC)silencingisdynein‐mediatedtransportofcertainkinetochoreproteinsalongmicrotubules.TherearestillconflictingdataastowhichSACproteinsaredyneincargoes.UsingtwoATPreductionassays,wefoundthatthecoreSACproteinsMad1,Mad2,Bub1,BubR1,andBub3redistributedfromattachedkinetochorestospindlepoles,inadynein‐dependentmanner.Thisredistributionstilloccurredinmetaphase‐arrestedcells,atatimewhentheSACshouldbesatisfiedandsilenced.Unexpectedly,wefoundthatapoolofHec1andMis12alsorelocalizestospindlepoles,suggestingKMNcomponentsasadditionaldyneincargoes.ThepotentialsignificanceoftheseresultsforSACsilencingisdiscussed...