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Mitotic spindle orients perpendicular to the forces imposed by dynamic shear.

ABSTRACT: Orientation of the division axis can determine cell fate in the presence of morphogenetic gradients. Understanding how mitotic cells integrate directional cues is therefore an important question in embryogenesis. Here, we investigate the effect of dynamic shear forces on confined mitotic cells. We found that human epithelial cells (hTERT-RPE1) as well as MC3T3 osteoblasts align their mitotic spindle perpendicular to the external force. Spindle orientation appears to be a consequence of cell elongation along the zero-force direction in response to the dynamic shear. This process is a nonlinear response to the strain amplitude, requires actomyosin activity and correlates with redistribution of myosin II. Mechanosteered cells divide normally, suggesting that this mechanism is compatible with biological functions.

SUBMITTER: Fernandez P

PROVIDER: S-EPMC3248423 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Mitotic spindle orients perpendicular to the forces imposed by dynamic shear.

Fernandez Pablo P Maier Matthias M Lindauer Martina M Kuffer Christian C Storchova Zuzana Z Bausch Andreas R AR

PloS one 20111229 12

Orientation of the division axis can determine cell fate in the presence of morphogenetic gradients. Understanding how mitotic cells integrate directional cues is therefore an important question in embryogenesis. Here, we investigate the effect of dynamic shear forces on confined mitotic cells. We found that human epithelial cells (hTERT-RPE1) as well as MC3T3 osteoblasts align their mitotic spindle perpendicular to the external force. Spindle orientation appears to be a consequence of cell elon ...[more]

PMID: 22220200

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