Dynamic Force Generation by Neural Stem Cells

  • P. Shi
  • K. Shen
  • S. Ghassemi
  • J. Hone
  • L. C. KamEmail author


Mechanical cues may have important roles in tissue morphogenesis; progression through complex functions like differentiation may be associated with changes in cellular force generation and mechanosensing. To explore this concept, we use elastomer pillar arrays to map forces generated by neural stem cells in vitro, and identify two distinct dynamics of force generation. First, cell generated forces decrease as cells transition from a proliferative mode to differentiation, a process covering several days. This change in force generation correlates with a loss of sensitivity to substrate rigidity over a series of polydimethylsiloxane substrates. Second, neural stem cells exhibit a faster pattern of localized contractions at the cell body and outlying processes; each lasts on the order of minutes, and is not synchronized across the cell. This faster process is reminiscent of migratory behavior observed in vivo, and may be involved in controlling the motion of internal structures such as the cell nucleus. These results together provide new clues into the role of forces during development, and may lead to design principles for materials targeted for use in the central nervous system.


Cellular traction force Stem cell Microenvironment Differentiation Proliferation 



This work was funded by the National Institutes of Health through the NIH Roadmap for Medical Research (PN2 EY016586).

Supplementary material

12195_2009_97_MOESM1_ESM.avi (4.8 mb)
Supplementary Figure 1 Pulsatile nuclear migration by radial-glia-like NSCs in vitro. The position of the nucleus in each frame was determined by fitting a oval to the cell body; the centroid of this structure is indicated by the green dot in each frame. The bottom frame compares average force generation under the nucleus and nucleus position as a function of time (AVI 4905 kb)
Supplementary Figure 2

Application of blebbstatin to cells in expansion media induces rapid changes in morphology. Corresponding effects on nuclear migration are quantified in Fig. 5D, E (AVI 3787 kb)

12195_2009_97_MOESM3_ESM.avi (8.5 mb)
Supplementary Figure 3 Cells differentiated from SVZ-NSCs were present as clusters migrating over each other in a pulsate mode, resembling “chain migration” of neuroblasts in the SVZ stem cell niche (AVI 8701 kb)
12195_2009_97_MOESM4_ESM.pdf (106 kb)
Supplementary Figure 4 Detail of molecular architecture shown in Fig. 4a, 1 DIV. µPAs were coated with fluorescently-labeled laminin (blue). The µPA array is the standard dimensions of 1 µm diameter, 2 µm center-to-center spacing, 7 µm height; the field of view of this image measures 133 µm across. Actin cytoskeleton and cell nuclei were stained with phalloidin (green) and DAPI (red), respectively. Image stacks were collected in standard epifluorescence mode then deconvoluted and projected onto the indicated visualization planes using standard image processing software (PDF 106 kb)
12195_2009_97_MOESM5_ESM.avi (4.8 mb)
Supplementary Figure 5 Transient, multisite force generation by NSCs in culture. Each time series was collected at 30 s intervals (showed at 1-min interval), covering a 10-min observation period (AVI 4935 kb)


  1. 1.
    Beningo, K. A., M. Dembo, I. Kaverina, J. V. Small, and Y. L. Wang. Nascent focal adhesions are responsible for the generation of strong propulsive forces in migrating fibroblasts. J. Cell Biol. 153:881–888, 2001.CrossRefGoogle Scholar
  2. 2.
    Burridge, K., and M. Chrzanowska-Wodnicka. Focal adhesions, contractility, and signaling. Annu. Rev. Cell Dev. Biol. 12:463–518, 1996.CrossRefGoogle Scholar
  3. 3.
    Cai, Y., N. Biais, G. Giannone, M. Tanase, G. Jiang, J. M. Hofman, C. H. Wiggins, P. Silberzan, A. Buguin, B. Ladoux, and M. P. Sheetz. Nonmuscle myosin IIA-dependent force inhibits cell spreading and drives F-actin flow. Biophys. J. 91:3907–3920, 2006.CrossRefGoogle Scholar
  4. 4.
    Campos, L. S., D. P. Leone, J. B. Relvas, C. Brakebusch, R. Fassler, U. Suter, and C. Ffrench-Constant. Beta1 integrins activate a MAPK signalling pathway in neural stem cells that contributes to their maintenance. Development 131:3433–3444, 2004.CrossRefGoogle Scholar
  5. 5.
    Conti, L., S. M. Pollard, T. Gorba, E. Reitano, M. Toselli, G. Biella, Y. Sun, S. Sanzone, Q. L. Ying, E. Cattaneo, and A. Smith. Niche-independent symmetrical self-renewal of a mammalian tissue stem cell. PLoS Biol. 3:e283, 2005.CrossRefGoogle Scholar
  6. 6.
    Dembo, M., and Y. L. Wang. Stresses at the cell-to-substrate interface during locomotion of fibroblasts. Biophys. J. 76:2307–2316, 1999.CrossRefGoogle Scholar
  7. 7.
    Doetsch, F., I. Caille, D. A. Lim, J. M. Garcia-Verdugo, and A. Alvarez-Buylla. Subventricular zone astrocytes are neural stem cells in the adult mammalian brain. Cell 97:703–716, 1999.CrossRefGoogle Scholar
  8. 8.
    du Roure, O., A. Saez, A. Buguin, R. H. Austin, P. Chavrier, P. Silberzan, and B. Ladoux. Force mapping in epithelial cell migration. Proc. Natl Acad. Sci. USA 102:2390–2395, 2005.CrossRefGoogle Scholar
  9. 9.
    Elkin, B. S., E. U. Azeloglu, K. D. Costa, and B. Morrison, 3rd. Mechanical heterogeneity of the rat hippocampus measured by atomic force microscope indentation. J. Neurotrauma 24:812–822, 2007.CrossRefGoogle Scholar
  10. 10.
    Engler, A. J., S. Sen, H. L. Sweeney, and D. E. Discher. Matrix elasticity directs stem cell lineage specification. Cell 126:677–689, 2006.CrossRefGoogle Scholar
  11. 11.
    Galbraith, C. G., and M. P. Sheetz. A micromachined device provides a new bend on fibroblast traction forces. Proc. Natl Acad. Sci. USA 94:9114–9118, 1997.CrossRefGoogle Scholar
  12. 12.
    Galbraith, C. G., K. M. Yamada, and M. P. Sheetz. The relationship between force and focal complex development. J. Cell Biol. 159:695–705, 2002.CrossRefGoogle Scholar
  13. 13.
    Ghassemi, S., N. Biais, K. Maniura, S. K. Wind, M. P. Sheetz, and J. Hone. Fabrication of elastomer pillar arrays with modulated stiffness for cellular force measurements. J. Vacuum Sci. Technol. B 26:2549–2553, 2008.CrossRefGoogle Scholar
  14. 14.
    Ghibaudo, M., A. Saez, L. Trichet, A. Xayaphoummine, J. Browaeys, P. Silberzan, A. Buguin, and B. Ladoux. Traction forces and rigidity sensing regulate cell functions. Soft Matter 4:1836–1843, 2008.CrossRefGoogle Scholar
  15. 15.
    Giannone, G., B. J. Dubin-Thaler, H. G. Dobereiner, N. Kieffer, A. R. Bresnick, and M. P. Sheetz. Periodic lamellipodial contractions correlate with rearward actin waves. Cell 116:431–443, 2004.CrossRefGoogle Scholar
  16. 16.
    Gotz, M., and W. B. Huttner. The cell biology of neurogenesis. Nat. Rev. Mol. Cell Biol. 6:777–788, 2005.CrossRefGoogle Scholar
  17. 17.
    Higginbotham, H. R., and J. G. Gleeson. The centrosome in neuronal development. Trends Neurosci. 30:276–283, 2007.CrossRefGoogle Scholar
  18. 18.
    Lathia, J. D., B. Patton, D. M. Eckley, T. Magnus, M. R. Mughal, T. Sasaki, M. A. Caldwell, M. S. Rao, M. P. Mattson, and C. Ffrench-Constant. Patterns of laminins and integrins in the embryonic ventricular zone of the CNS. J. Comp. Neurol. 505:630–643, 2007.CrossRefGoogle Scholar
  19. 19.
    Leone, D. P., J. B. Relvas, L. S. Campos, S. Hemmi, C. Brakebusch, R. Fassler, C. Ffrench-Constant, and U. Suter. Regulation of neural progenitor proliferation and survival by beta1 integrins. J. Cell Sci. 118:2589–2599, 2005.CrossRefGoogle Scholar
  20. 20.
    Lim, D. A., and A. Alvarez-Buylla. Interaction between astrocytes and adult subventricular zone precursors stimulates neurogenesis. Proc. Natl Acad. Sci. USA 96:7526–7531, 1999.CrossRefGoogle Scholar
  21. 21.
    Lin, Y.-W., C.-M. Cheng, P. R. LeDuc, and C.-C. Chen. Understanding sensory nerve mechanotransduction through localized elastomeric matrix control. PLoS ONE 4:e4293, 2009.CrossRefGoogle Scholar
  22. 22.
    Mercier, F., J. T. Kitasako, and G. I. Hatton. Anatomy of the brain neurogenic zones revisited: fractones and the fibroblast/macrophage network. J. Comp. Neurol. 451:170–188, 2002.CrossRefGoogle Scholar
  23. 23.
    Palmer, T. D., E. A. Markakis, A. R. Willhoite, F. Safar, and F. H. Gage. Fibroblast growth factor-2 activates a latent neurogenic program in neural stem cells from diverse regions of the adult CNS. J. Neurosci. 19:8487–8497, 1999.Google Scholar
  24. 24.
    Ridley, A. J., M. A. Schwartz, K. Burridge, R. A. Firtel, M. H. Ginsberg, G. Borisy, J. T. Parsons, and A. R. Horwitz. Cell migration: integrating signals from front to back. Science 302:1704–1709, 2003.CrossRefGoogle Scholar
  25. 25.
    Saez, A., A. Buguin, P. Silberzan, and B. Ladoux. Is the mechanical activity of epithelial cells controlled by deformations or forces? Biophys. J. 89:L52–L54, 2005.CrossRefGoogle Scholar
  26. 26.
    Saha, K., A. J. Keung, E. F. Irwin, Y. Li, L. Little, D. V. Schaffer, and K. E. Healy. Substrate modulus directs neural stem cell behavior. Biophys. J. 95:4426–4438, 2008.CrossRefGoogle Scholar
  27. 27.
    Sbalzarini, I. F., and P. Koumoutsakos. Feature point tracking and trajectory analysis for video imaging in cell biology. J. Struct. Biol. 151:182–195, 2005.CrossRefGoogle Scholar
  28. 28.
    Schaar, B. T., and S. K. McConnell. Cytoskeletal coordination during neuronal migration. Proc. Natl Acad. Sci. USA 102:13652–13657, 2005.CrossRefGoogle Scholar
  29. 29.
    Tan, J. L., J. Tien, D. M. Pirone, D. S. Gray, K. Bhadriraju, and C. S. Chen. Cells lying on a bed of microneedles: an approach to isolate mechanical force. Proc. Natl Acad. Sci. USA 100:1484–1489, 2003.CrossRefGoogle Scholar
  30. 30.
    Tsai, J., and L. Kam. Rigidity-dependent cross talk between integrin and cadherin signaling. Biophys. J. 96:L39–L41, 2009.CrossRefGoogle Scholar
  31. 31.
    Tsai, J. W., K. H. Bremner, and R. B. Vallee. Dual subcellular roles for LIS1 and dynein in radial neuronal migration in live brain tissue. Nat. Neurosci. 10:970–979, 2007.CrossRefGoogle Scholar
  32. 32.
    Tsai, J. W., Y. Chen, A. R. Kriegstein, and R. B. Vallee. LIS1 RNA interference blocks neural stem cell division, morphogenesis, and motility at multiple stages. J. Cell Biol. 170:935–945, 2005.CrossRefGoogle Scholar
  33. 33.
    Ulrich, T. A., E. M. de Juan Pardo, and S. Kumar. The mechanical rigidity of the extracellular matrix regulates the structure, motility, and proliferation of glioma cells. Cancer Res. 69:4167–4174, 2009.CrossRefGoogle Scholar
  34. 34.
    Wichterle, H., J. M. Garcia-Verdugo, and A. Alvarez-Buylla. Direct evidence for homotypic, glia-independent neuronal migration. Neuron 18:779–791, 1997.CrossRefGoogle Scholar
  35. 35.
    Wozniak, M. A., R. Desai, P. A. Solski, C. J. Der, and P. J. Keely. ROCK-generated contractility regulates breast epithelial cell differentiation in response to the physical properties of a three-dimensional collagen matrix. J. Cell Biol. 163:583–595, 2003.CrossRefGoogle Scholar
  36. 36.
    Zajac, A. L., and D. E. Discher. Cell differentiation through tissue elasticity-coupled, myosin-driven remodeling. Curr. Opin. Cell Biol. 20:609–615, 2008.CrossRefGoogle Scholar

Copyright information

© Biomedical Engineering Society 2009

Authors and Affiliations

  • P. Shi
    • 1
  • K. Shen
    • 1
  • S. Ghassemi
    • 2
  • J. Hone
    • 2
  • L. C. Kam
    • 1
    Email author
  1. 1.Department of Biomedical EngineeringColumbia UniversityNew YorkUSA
  2. 2.Department of Mechanical EngineeringColumbia UniversityNew YorkUSA

Personalised recommendations