Centrosome reorientation in wound-edge cells is cell type specific.
The reorientation of the microtubule organizing center during cell migration into a wound in the monolayer was directly observed in living wound-edge cells expressing gamma-tubulin tagged with green fluorescent protein. Our results demonstrate that in CHO cells, the centrosome reorients to a position in front of the nucleus, toward the wound edge, whereas in PtK cells, the centrosome lags behind the nucleus during migration into the wound. In CHO cells, the average rate of centrosome motion was faster than that of the nucleus; the converse was true in PtK cells. In both cell lines, centrosome motion was stochastic, with periods of rapid motion interspersed with periods of slower motion. Centrosome reorientation in CHO cells required dynamic microtubules and cytoplasmic dynein/dynactin activity and could be prevented by altering cell-to-cell or cell-to-substrate adhesion. Microtubule marking experiments using photoactivation of caged tubulin demonstrate that microtubules are transported in the direction of cell motility in both cell lines but that in PtK cells, microtubules move individually, whereas their movement is more coherent in CHO cells. Our data demonstrate that centrosome reorientation is not required for directed migration and that diverse cells use distinct mechanisms for remodeling the microtubule array during directed migration.
Yvon
Anne-Marie C
AM
Department of Biology and Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, MA 01002, USA.
Walker
Jonathan W
JW
Danowski
Barbara
B
Fagerstrom
Carey
C
Khodjakov
Alexey
A
Wadsworth
Patricia
P
D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology; D002467:Cell Nucleus / Q000648:ultrastructure; D048429:Cell Size / Q000502:physiology*; D018385:Centrosome / Q000502:physiology / Q000648:ultrastructure*; D006224:Cricetinae; D019084:Fluorescent Antibody Technique, Indirect; D049452:Green Fluorescent Proteins; D007700:Kinetics; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D014404:Tubulin / Q000235:genetics / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*
D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D014404:Tubulin; D049452:Green Fluorescent Proteins