Excess centrosomes perturb dynamic endothelial cell repolarization during blood vessel formation.
Blood vessel formation requires dynamic movements of endothelial cells (ECs) within sprouts. The cytoskeleton regulates migratory polarity, and centrosomes organize the microtubule cytoskeleton. However, it is not well understood how excess centrosomes, commonly found in tumor stromal cells, affect microtubule dynamics and interphase cell polarity. Here we find that ECs dynamically repolarize during sprouting angiogenesis, and excess centrosomes block repolarization and reduce migration and sprouting. ECs with excess centrosomes initially had more centrosome-derived microtubules but, paradoxically, fewer steady-state microtubules. ECs with excess centrosomes had elevated Rac1 activity, and repolarization was rescued by blockade of Rac1 or actomyosin blockers, consistent with Rac1 activity promoting cortical retrograde actin flow and actomyosin contractility, which precludes cortical microtubule engagement necessary for dynamic repolarization. Thus normal centrosome numbers are required for dynamic repolarization and migration of sprouting ECs that contribute to blood vessel formation.
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
Erich J
EJ
Kushner
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
Luke S
LS
Ferro
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
Zhixian
Z
Yu
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 bautch@med.unc.edu.
Victoria L
VL
Bautch
D008841:Actin Cytoskeleton; D000199:Actins; D000205:Actomyosin; D001808:Blood Vessels / Q000378:metabolism / Q000502:physiology; D018929:Cell Culture Techniques; D016764:Cell Polarity / Q000502:physiology; D018385:Centrosome / Q000378:metabolism* / Q000502:physiology*; D003599:Cytoskeleton; D004398:Dyneins; D042783:Endothelial Cells / Q000378:metabolism*; D006801:Humans; D008870:Microtubules / Q000378:metabolism; D014404:Tubulin; D020830:rac1 GTP-Binding Protein / Q000235:genetics / Q000378:metabolism
D000199:Actins; D014404:Tubulin; D000205:Actomyosin; D004398:Dyneins; D020830:rac1 GTP-Binding Protein