The Sawai research group aims to understand how the dynamics of “form” in biology emerges at cell and tissue-level with emphasis on the role of cell deformation, movement, cell-cell communication and cell type differentiation. Students and postdoctoral fellows in the lab choose to incorporate a variety of approaches including cell and molecular biology, biophysics, mathematical biology and microfabrication. Our strength lies at quantitative and physical biology based approach using live-cell imaging. The lab currently work on social amoeba Dictoystelium, naegleria gruberi, neutrophils and zebrafish to address following questions:

• How are spatial and temporal features of the extracellular cues such as chemoattractant and extracellular matrices interpreted by the cells to determine the direction of cell migration?
• How are the spatial and temporal ordering of actin cytoskeleton coordinated to facilitate basic cellular processes that require large-scale cell deformation such as cytokinesis, cell migration, macropinocytosis?
• How navigational rules of individual cells impact tissue-level patterning.
• How is cell-type proportioning regulated and how is it related to metabolism and cell survival strategies?

Keywords

self-organization, cell–cell signaling, cAMP, live-cell imaging, mathematical modeling, quantitative biology, systems biology, microfluidics-based devices, laser scanning microscope, Dictyostelium discoideum, leukocyte

Key publications

• T. Fujimori, A. Nakajima, N. Shimada, S. Sawai (2019) Tissue self-organization based on collective cell migration by contact activation of locomotion and chemotaxis Proc. Natl. Acad. Sci. USA 116, 4291-4296.
• A. Nakajima, S. Ishihara, D. Imoto and S. Sawai (2014) Recified directional sensing in long range cell migration. Nat. Commun. 5, 5367.
• T. Gregor, K. Fujimoto, N. Masaki and S. Sawai (2010) The onset of collective behavior in social amoebae.  Science 328, 1021-1025.
• S. Sawai, P.T. Thomason and E.C. Cox  (2005) An autoregulatory circuit for long-range self-organization in Dictyostelium cell populations. Nature 433, 323-326.