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Updated: May 26, 2026
10:52
Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets
Published on: August 13, 2016
Mitotic spindle orients perpendicular to the forces imposed by dynamic shear
Pablo Fernandez1, Matthias Maier, Martina Lindauer
1E27 Zellbiophysik, Technische Universität München, Garching bei München, Germany. pablo.fernandez@mytum.de
Plos One
|January 6, 2012
Summary
Mitotic cells, like human epithelial cells, align their division axis perpendicular to external shear forces. This mechanosensing response, driven by actomyosin activity, ensures normal cell division and is crucial for embryogenesis.
Area of Science:
- Cell Biology
- Biophysics
- Developmental Biology
Background:
- Cell division orientation is critical for cell fate determination during embryogenesis.
- Understanding how cells sense and respond to external directional cues is essential.
Purpose of the Study:
- To investigate the impact of dynamic shear forces on the orientation of the mitotic spindle in confined cells.
- To elucidate the cellular mechanisms underlying mechanosensing and spindle alignment.
Main Methods:
- Utilized human epithelial cells (hTERT-RPE1) and MC3T3 osteoblasts cultured under dynamic shear stress.
- Observed and quantified mitotic spindle orientation and cell elongation using microscopy.
- Analyzed the role of actomyosin contractility and myosin II distribution.
Main Results:
- Confined mitotic cells consistently aligned their spindle axis perpendicular to the applied dynamic shear force.
- Cellular response involved elongation along the zero-force direction, a nonlinear function of strain amplitude.
- Actomyosin activity and myosin II redistribution were necessary for this force-directed spindle orientation.
Conclusions:
- Mitotic cells possess a robust mechanism to orient their division axis in response to external mechanical forces.
- This mechanosensitive process, involving cell elongation and actomyosin dynamics, is compatible with normal cell division.
- Findings provide insights into how mechanical cues guide cell fate during development.
Related Concept Videos
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During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis.
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02:11Forces Acting on Chromosomes
During mitosis, chromosome movements occur through the interplay of multiple piconewton level forces. In prometaphase, these forces help in chromosome assembly or congression at the equatorial plane, eventually leading to their alignment at the metaphase plate. The forces acting on the chromosomes are space and time-dependent; therefore, they vary with the position of the chromosomes as the cell progresses through mitosis.
Microtubules and motor proteins exert two types of forces on...
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The mitotic spindle—or spindle apparatus—is a eukaryotic, cytoskeletal structure made up of long protein fibers called microtubules. Formed during cell division, the spindle separates sister chromatids and moves them to opposite ends of a parental cell, where the now individual chromosomes are distributed to two daughter cell nuclei.
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...
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