Quarterly Reviews of Biophysics

Review Article

Electron tomography of cells

Lu Gana1 and Grant J. Jensena1a2 c1

a1 Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA

a2 Howard Hughes Medical Institute, California Institute of Technology, Pasadena, CA 91125, USA

Abstract

The electron microscope has contributed deep insights into biological structure since its invention nearly 80 years ago. Advances in instrumentation and methodology in recent decades have now enabled electron tomography to become the highest resolution three-dimensional (3D) imaging technique available for unique objects such as cells. Cells can be imaged either plastic-embedded or frozen-hydrated. Then the series of projection images are aligned and back-projected to generate a 3D reconstruction or ‘tomogram’. Here, we review how electron tomography has begun to reveal the molecular organization of cells and how the existing and upcoming technologies promise even greater insights into structural cell biology.