摘要
Microtubules grow not only from the centrosome but also from various noncentrosomal microtubule-organizing centers(MTOCs),including the nuclear envelope(NE)and pre-existing microtubules.The evolutionarily conserved proteins Mtol/CDK5RAP2 and Alpl4/TOG/XMAP215 have been shown to be involved in promoting microtubule nucleation.However,it has remained elusive as to how the microtubule nucleation promoting factors are specified to various noncentrosomal MTOCs,particularly the NE,and how these proteins coordinate to organize microtubule assembly.Here,we demonstrate that in the fission yeast Schizosaccharomyces pombe,efficient interphase microtubule growth from the NE requires Alp7/TACC,Alpl4/TOG/XMAP215,and Mtol/CDK5RAP2.The absence of Alp7,A lp l4 t or Mtol compromises microtubule regrowth on the NE in cells undergoing microtubule repolymerization.We further demonstrate that Alp7 and Mtol interdependently localize to the NE in cells without microtubules and that A lp l4 localizes to the NE in an Alp7 and Mtol-dependent manner.Tethering Mtol to the NE in cells lacking Alp7 partially restores microtubule number and the efficiency of microtubule generation from the NE.Hence,our study delineates that Alp7,A lpl4,and Mtol work in concert to regulate interphase microtubule regrowth on the NE.
基金
the National Key Research and Development Program of China(2017YFA0503600)
the National Natural Science Foundation of China(91754106,31871350,31671406,31601095,and 31621002)
the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB19040101)
the Major/lnnovative Program of Development Foundation of Hefei Center for Physical Science and Technology(2017FXCX008)
China’s 1000 Young Talents Recruitment Program.
