Actin filaments and associated proteins undergo wave-like movement in various cell types. We reported that axonal actin waves migrate by means of directional assembly and disassembly of membrane-anchored actin filaments. Thus, the actin wave in axons represents a new type of machinery that translocates actin and associated proteins to the cell edge. The involvement of actin waves in axon outgrowth was also demonstrated by laser-manipulation of the adhesion substrate. We are currently analyzing roles of actin waves in cell polarity formation and migration, introducing single molecule imaging and mathematical modeling.

Actin waves traveling along an axon

High resolution imaging of an actin wave

Mechanism for actin wave migration and protein transport along axons

Reference

1. Inagaki, N., Katsuno, H. (2017)
   Actin Waves: Origin of Cell Polarization and Migration?, Trends in Cell Biology 27, 515-526 (LINK)
2. Katsuno, H., Toriyama, M., Hosokawa, Y., Mizuno, K., Ikeda, K., Sakumura, Y, and Inagaki, N. (2015)
   Actin migration driven by directional assembly and disassembly of membrane anchored actin filaments, Cell Reports 12, 648-660.(LINK)
3. Inagaki, N.,Toriyama, M. and Sakumura, Y.(2011)
   Systems biology of symmetry-breaking during neuronal polarity formation, Dev. Neurobiol.71,584-593.(LINK)
4. Toriyama, M., Sakumura, Y., Shimada, T., Ishii, S. and Inagaki, N.(2010)
   A diffusion-based neurite length sensing mechanism involved in neuronal symmetry-breaking, Mol.Syst.Biol. 6, 394.(LINK)
5. Toriyama, M., Shimada, T., Kim, K-B., Mitsuba, M., Nomura, E., Katsuta, K., Sakumura, Y., Roepstorff, P., and Inagaki, N. (2006)
   Shootin1: a protein involved in the organization of an asymmetric signal for neuronal polarization.J. Cell Biol. 175, 147-157.(LINK)