Mitochondrial displacements in response to nanomechanical forces
Yaron R Silberberg1, Andrew E Pelling, Gleb E Yakubov
1The London Centre for Nanotechnology and Centre for NanoMedicine, University College London, 17-19 Gordon Street, London, WC1H 0AH, UK.
Journal of Molecular Recognition : JMR
|February 6, 2008
Summary
Mechanical stress significantly impacts cell structures. Applying nanomechanical forces to fibroblast cells caused substantial mitochondrial displacement, highlighting the cytoskeleton
Area of Science:
- Cellular Mechanobiology
- Biophysics
- Cytoskeletal Dynamics
Background:
- Mechanical stress is a critical regulator of cellular functions, influencing morphology, growth, differentiation, gene expression, and apoptosis.
- Understanding how cells respond mechanically at the intracellular level is crucial for comprehending various physiological and pathological processes.
Purpose of the Study:
- To investigate the direct effects of nanomechanical stress on intracellular structures, specifically mitochondrial dynamics within live cells.
- To correlate applied mechanical perturbations with cellular mechanical responses and explore the role of the cytoskeleton in force transmission.
Main Methods:
- Utilized a combined fluorescence-atomic force microscope (AFM) to apply precise nanomechanical perturbations (10 nN) to live fibroblast cells.
- Simultaneously tracked the real-time motion of fluorescently labeled mitochondria to quantify organelle displacement in response to mechanical loads.
- Investigated the role of the actin and microtubule cytoskeleton by disrupting them with Cytochalasin D and Nocodazole, respectively.
Main Results:
- Applied nanomechanical forces induced significant spatial displacement of mitochondria, averaging an increase of approximately 40% (160 nm vs. 110 nm basal).
- Observed organelle displacements occurred at distances far from the initial point of force application (up to approximately 40 micrometers).
- Disruption of the actin and microtubule cytoskeleton did not significantly alter mitochondrial displacement, suggesting a complex role in force transmission.
Conclusions:
- The cytoskeleton plays a role in transmitting mechanical forces through the cell, influencing intracellular organelle displacement.
- Local mechanical perturbations applied via AFM can induce substantial intracellular structural responses, affecting organelles like mitochondria.
- Caution is advised when conducting AFM mechanical experiments on living cells due to potential significant structural and biochemical effects.
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