Structural Studies by Electron Tomography and Image Processing


Our research interests are mainly focused on structural analysis of specimens of biological relevance by means of electron tomography and image processing. We are exploring the structural alterations in the sub-cellular architecture under normal and pathological conditions in neurodegenerative diseases. We are also interested in structural elucidation of the microtubule organizing centre (MTOC), an important and complex cellular organelle in eukaryotes, in close collaboration with Dr. Sam Li (UCSF). We also collaborate with cellular and molecular biology groups in other experimental structural studies. An important pillar of our research is the development and application of computational methods and tools for electron tomography.

 
A.Three-dimensional structure of the basal body triplet revealed by electron cryotomography and subtomogram averaging at 33 Angstroms resolution, and model for the whole basal body. (Li et al. EMBO J, 2012).
B. 80S ribosome macromolecular atlas from a vitreous section of a Saccharomyces cerevisiae cell using electron tomography and image processing. Mitochondrion, purple; vacuole, blue; endoplasmic reticulum, pink; cell membrane, white; unidentified vesicle structures, green; unidentified macromolecular complexes including putative ribosomes, yellow. Top panels show a putative polyribosome cluster and an average ribosome. (Pierson et al., J.Struct.Biol., 2010).

C. Visualization of the structure of Hepatitis B virus with electron tomography and new computational methods for determination and correction of the transfer function of the electron microscope and subtomogram averaging techniques. (Fernandez et al. Ultramicroscopy, 2006).
D. Structure of the connector of T7 bacteriophage at sub-nanometer resolution after the application of a computational technique for sharpening the high-resolution information. (Fernandez et al., J.Struct.Biol., 2008).
E. Structure of the connector of phi29 bacteriophage at 10 Angstroms resolution determined by electron crystallography and image processing. (Valpuesta et al., Structure 1999).