Quantitative 3D imaging of whole, unstained cells by using X-ray diffraction microscopy.
Microscopy has greatly advanced our understanding of biology. Although significant progress has recently been made in optical microscopy to break the diffraction-limit barrier, reliance of such techniques on fluorescent labeling technologies prohibits quantitative 3D imaging of the entire contents of cells. Cryoelectron microscopy can image pleomorphic structures at a resolution of 3-5 nm, but is only applicable to thin or sectioned specimens. Here, we report quantitative 3D imaging of a whole, unstained cell at a resolution of 50-60 nm by X-ray diffraction microscopy. We identified the 3D morphology and structure of cellular organelles including cell wall, vacuole, endoplasmic reticulum, mitochondria, granules, nucleus, and nucleolus inside a yeast spore cell. Furthermore, we observed a 3D structure protruding from the reconstructed yeast spore, suggesting the spore germination process. Using cryogenic technologies, a 3D resolution of 5-10 nm should be achievable by X-ray diffraction microscopy. This work hence paves a way for quantitative 3D imaging of a wide range of biological specimens at nanometer-scale resolutions that are too thick for electron microscopy.
Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA.
Huaidong
H
Jiang
Changyong
C
Song
Chien-Chun
CC
Chen
Rui
R
Xu
Kevin S
KS
Raines
Benjamin P
BP
Fahimian
Chien-Hung
CH
Lu
Ting-Kuo
TK
Lee
Akio
A
Nakashima
Jun
J
Urano
Tetsuya
T
Ishikawa
Fuyuhiko
F
Tamanoi
Jianwei
J
Miao
D000465:Algorithms; D020285:Cryoelectron Microscopy / Q000379:methods*; D004583:Electrons; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008954:Models, Biological; D015233:Models, Statistical; D055095:Optics and Photonics; D012542:Scattering, Radiation; D012568:Schizosaccharomyces / Q000378:metabolism / Q000502:physiology*; D013172:Spores, Fungal / Q000378:metabolism; D014961:X-Ray Diffraction / Q000379:methods*; D014965:X-Rays; D015003:Yeasts / Q000378:metabolism