Assistant Professor

Contact Information:

Department of Biological Science
National University of Singapore
14 Science Drive 4
Singapore 117543

Additional Affiliations:

Principal Investigator, Mechanobiology Institute, Singapore
Principal Investigator, Temasek Life Sciences Laboratory

Contact Information:

National University of Singapore
5A Engineering Drive 1
Singapore 117411

6601 1273

Academic Qualifications

2003-2010 Postdoctoral Fellow, Physics department and Free Electron Laser Lab, Duke University, USA
2003 Postdoctoral Fellow, Institute of Laser Engineering, Osaka University, Japan
2003 Ph.D., Osaka University, Japan
2000 M.E., Osaka University, Japan
1998 B.E., Hokkaido University, Japan

Research Areas

Developmental biology, Mechanobiology of cells and tissues, Biophysics, and Bioimaging.

Research Interests

In embryonic development, mechanical forces exerted by cells and tissues play a predominant role. Cells can actively produce forces and can provide a passive response, making the process of morphogenesis larger than the sum of individual cells. The extraction of mechanical signature from cell / tissue dynamics using a multidisciplinary approach, including imaging, quantitative analysis, gene manipulation, biophysical instruments and techniques, and modeling is fundamental to our research.

We use Drosophila and cell lines as model systems to uncover:

  • Spatially coordinated and temporally synchronized collective cell behaviors underlying tissue morphogenesis;
  • Effects of spatial and geometric constraints of microenvironment on cell / tissue dynamics;
  • Role of apoptotic process on tissue dynamics (see Toyama at el, 2008).

Selected Publications

See Latest Publications

  1. Sun Z, Amourda C, Shagirov M, Hara Y, Saunders TE, Toyama Y. “Basolateral protrusion and apical contraction cooperatively drive Drosophila germband extension.” Nature Cell Biology (2017, in press)

  2. Saw TB, Doostmohammadi A, Nier V, Kocgozlu L, Thampi S, Toyama Y, Marcq P, Lim CT*, Yeomans JM*, Ladoux B* “Topological defects in epithelia govern cell death and extrusion” Nature (2017, in press)

  3. Teng X, Qin L, Le Borgne R, Toyama Y. “Remodeling of adhesion and modulation of mechanical tensile forces during apoptosis in Drosophila epithelium” Development 144, 95-105 (2017)

  4. Bertocchi C, Wang Y, Ravasio A, Hara Y, Wu Y, Sailov T, Baird MA, Davidson MW, Zaidel-Bar R, Toyama Y, Ladoux B, Mege RM, Kanchanawong P. “Nanoscale architecture of cadherin-based cell adhesions” Nature Cell Biology 19, 28-37 (2017)

  5. Kocgozlu L*, Saw TB*, Le AP, Yow I, Shagirov M, Wong E, Mège RM, Lim CT, Toyama Y**, Ladoux B** *, **: Equal contribution “Epithelial cell packing induces distinct modes of cell extrusions” Current Biology 26, 2942-50 (2016)

  6. Hara Y, Shagirov M, Toyama Y. “Cell boundary elongation by non-autonomous contractility in cell oscillation” Current Biology 26, 2388-96 (2016)

  7. Ravasio A, Cheddadi I, Chen T, Pereira T, Ong HT, Bertocchi C, Brugues A, Jacinto A, Kabla AJ, Toyama Y, Trepat X, Gov N, Neves de Almeida L, Ladoux B. “Gap geometry dictates epithelial closure efficiency” Nature Communications 6, 7683 (2015)

  8. Vedula S.R.K, Peyret G, Cheddadi I, Chen T, Brugués A, Hirata H, Lopez-Menendez H, Toyama Y, Almeida L, Trepat X, Lim CT, Ladoux B  “Mechanics of epithelial closure over non-adherent environments” Nature Communications 6, 6111 (2015)

  9. Kawashima T, Maruyama D, Shagirov M, Hamamura Y, Li J, Yelagandula R, Toyama Y, Berger F “Dynamic F-actin movement is essential for fertilization in Arabidopsis thaliana” eLife 3, 04501 (2014)

  10. Vedula S.R.K, Hirata H, Nai MH, Brugés A, Toyama Y, Trepat X, Lim CT and Ladoux B.  “Epithelial bridges maintain tissue integrity during collective cell migration” Nature Material 13, 87–96 (2014)

  11. Sokolow, A, Toyama, Y, Kiehart, D.P. and Edwards, G.S. “Cell ingression and apical shape oscillations during dorsal closure in Drosophila” Biophysical Journal 102, 969-979 (2012)     

  12. Teng, X, Toyama Y. “Apoptotic force: Active mechanical function of cell death during morphogenesis” Development Growth and Differentiation. 53, 269-276 (2011) Review

  13. Layton, A.T.,* Toyama, Y.,* Yang, G-Q.,* Edwards, G.S., Kiehart, D.P., Venakides, S. *: Equal contribution. "Drosophila Morphogenesis: Tissue Force Laws and the Modeling of Dorsal Closure" HFSP (Human Frontier Science Program) Journal 3, 441-460 (2009). 

  14. Toyama, Y., Peralta, X.G., Wells, A.R., Kiehart, D.P., and Edwards, G.S. "Apoptotic force and tissue dynamics during Drosophila embryogenesis" Science 321, 1683-1686 (2008).

  15. Rodriguez-Diaz, A., Toyama, Y., Abravanel, D.L., Wiemann, J.M., Wells, A.R., Tulu, U.S., Edwards, G.S., and Kiehart, D.P. "Actomyosin purse strings: renewable resources that make morphogenesis robust and resilient" HFSP Journal 2, 220-237 (2008).

  16. Peralta, X.G., Toyama, Y., Kiehart, D.P., and Edwards, G.S. "Emergent properties during dorsal closure in Drosophila morphogenesis" Physical Biology 5, 015004 (2008).

  17. Peralta, X.G., Toyama, Y., Hutson, M.S., Montague, R., Venakides, S., Kiehart, D.P., and Edwards, G.S. "Upregulation of forces and morphogenic asymmetries in dorsal closure during Drosophila development" Biophysical Journal 92, 2583-2596 (2007).

  18. Kiehart, D.P., Tokutake, Y., Chang, M.S., Hutson, M.S., Wiemann, J., Peralta, X.G., Toyama, Y., Wells, A.R., Rodriguez, A., and Edwards, G.S.  "Ultraviolet Laser Microbeam for Dissection of Drosophila Embryos. " Cell Biology: A Laboratory Handbook, 3rd edition, edited by J.E. Celis (2006), pp. 87-103, Elsevier (Chapter 9)