Centering of a radial microtubule array by translocation along microtubules spontaneously nucleated in the cytoplasm.
Positioning of a radial array of microtubules (MTs) in the cell centre is crucial for cytoplasmic organization, but the mechanisms of such centering are difficult to study in intact cells that have pre-formed radial arrays. Here, we use cytoplasmic fragments of melanophores, and cytoplasts of BS-C-1 cells to study MT centering mechanisms. Using live imaging and computer modelling, we show that the MT aster finds a central location in the cytoplasm by moving along spontaneously nucleated non-astral MTs towards a point at which MT nucleation events occur equally on all sides. We hypothesize that similar mechanisms, in the presence of the centrosome, contribute to this centering mechanism and ensure the robustness of cytoplasmic organization.
Malikov
Viacheslav
V
Department of Cell Biology and Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06032-1507, USA.
Cytrynbaum
Eric N
EN
Kashina
Anna
A
Mogilner
Alexander
A
Rodionov
Vladimir
V
D000818:Animals; D018385:Centrosome; D003198:Computer Simulation; D003460:Crystallization; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure*; D003952:Diagnostic Imaging; D006801:Humans; D008547:Melanophores / Q000648:ultrastructure; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure*; D021381:Protein Transport