Laboratory for Cell Field Structure | RIKEN BDR

Laboratory for Cell Field Structure

Unit Leader

Atsuko IwanePh.D.

  • Location:Hiroshima
  • E-mail:atsuko.iwane[at]riken.jpPlease replace [at] with @.

Research Summary

Electron microscopy (EM) offers the best in resolution of extremely small biological specimens, providing images of the minutest of organelles and molecules that are responsible for phenomena fundamental to life including cell division, differentiation and proliferation. The resulting fine structural information has been extraordinary in helping our understanding of how morphology and function relate.  We seek to image several target molecules and organelles, including the mitochondria and chloroplasts, and their surrounding environments inside a cell by using two different electron microscopy technologies. The first is Cryo-EM tomography, which produces a 3D image by scanning the field of view at multiple angles over an angular range from -70 degrees to 70 degrees relative to the perpendicular of the specimen plane used in transmission electron microscopy (TEM). The second is focused ion beam scanning electron microscopy (FIB-SEM), which uses SEM to scan a number of sections that are created by FIB. In this aim, we will combine our electron microscopy system with fluorescence microscopy to conduct dual imaging of the specimen in the same field of view. This will provide information on the dynamics of the specimen, which will complement the structure information and give us better understanding of the relationship between cell fate and cell morphology.

Research Theme

  • Development of stainless cell imaging by Cryo-TEM
  • Whole cell structure reconstruction by three-dimensional FIB-SEM

Main Publications List

  • Fujii T, Iwane AH, Yanagida T, Namba K.
    Direct visualization of secondary structures of F-actin by electron cryomicroscopy.
    Nature 467(7316). 724-728 (2010) doi: 10.1038/nature09372
  • Nishikawa S, Arimoto I, Ikezaki K, et al.
    Switch between Large Hand-Over-Hand and Small Inchworm-like Steps in Myosin VI.
    Cell 142(6). 879-888 (2010) doi: 10.1016/j.cell.2010.08.033
  • Watanabe TM, Yanagida T, Iwane AH.
    Single molecular observation of self-regulated kinesin motility.
    Biochemistry, 49, 4654-4661, (2010) doi: 10.1021/bi9021582.
  • Iwane AH, Morimatsu M, Yanagida T.
    Recombinant alpha-actin for specific fluorescent labeling.
    Proceedings of the Japan Academy Series B-Physical and Biological Sciences 85(10). 491-499 (2009) doi: 10.2183/pjab.85.491
  • Iwaki M, Iwane AH, Shimokawa T, et al.
    Brownian search-and-catch mechanism for myosin-VI steps.
    Nature Chemical Biology 5(6). 403-405 (2009) doi: 10.1038/nchembio.171
  • Iwane AH. Tanaka H, Morimoto S, et al.
    The neck domain of myosin II primarily regulates the actomyosin kinetics, not the 10.1016/j.jmb.2005.08.013stepsize.
    Journal of Molecular Biology, 353, 213-221, (2005) doi: 10.1016/j.jmb.2005.08.013
  • Tanaka H, Homma K, Iwane AH, et al.
    The motor domain determines the large step of myosin-V.
    Nature, 415, 192-195, (2002) doi: 10.1038/415192a
  • Kitamura K, Tokunaga M, Iwane AH, Yanagida T.
    A single myosin head moves along an actin filament with regular steps of 5.3 nanometres.
    Nature, 397, 129-134, (1999) doi: 10.1038/16403
  • Iwane AH, Funatsu T, Harada Y, et al.
    Single molecular assay of the individual ATP turnovers by a myosin-GFP fusion protein expressed in vitro.
    FEBS Letters, 407, 235-238, (1997) doi: 10.1016/S0014-5793(97)00359-1
  • Iwane AH, Kitamura K, Tokunaga M, Yanagida T.
    Myosin subfragment-1 is fully equipped with factors essential for motor function.
    Biochemical and Biophysical Research Communications, 230, 76-80, (1997) doi: 10.1006/bbrc.1996.5861