Sam Li

Department of Biochemistry & Biophysics
University of California, San Francisco
600 16th St, Room S416
San Francisco CA
94158-2517
(415) 502-2930 (Ph)
(415) 476-1902 (Fax)
email

Research

My main research goal is to elucidate the function of the microtubule organizing center (MTOC). The MTOC is an important and complex cellular organelle in eukaryotes. It regulates cell motility and determines cell polarity in interphase and is required for normal cell division during mitosis and meiosis. The MTOC is highly dynamic and tightly regulated during the cell cycle. Defects in centrosomes, one of the MTOCs in mammalian cells, are linked to many human diseases such as cancer, Huntington’s disease and genetic disorders. Currently I am focusing on two eukaryotic MTOCs, the spindle pole body (SPB) from the budding yeast Saccharomyces cerevisiae and the centriole/basal body from the low plants and mammals. The objectives of the research are; 1) biochemical characterization and structure determination of major compositions of the MTOC; 2) elucidation of the supermolecular assembly the MTOC; 3) combining structure, biochemistry and cell biology information to obtain insights into the molecular mechanism and the cellular functions.

Publications: 

"Three-dimensional structure of basal body triplet revealed by electron cryo-tomography." Li S, Fernandez JJ, Marshall WF, Agard DA. EMBO J. (2011), 31(3), 552-62. (pdf)

Berriman, J.A., Li, S., Hewlett, L.J., Kiskin, F, Carter, T., Hannah, M.J., Rosenthal, P.B. (2009) Structural Organization of Weibel-Palade Bodies Revealed by Cryo-EM of Vitrified Endothelial Cells. Proc. Natl. Acad. Sci. USA. 106, 17407-17412.

Hirst, J., Sahlender, D.A., Li, S., Lubben, N.B., Borner, G.H.H., Robinson, M.S. (2008). Auxilin Depletion Causes Self-assembly of Clathrin into Membraneless Cages in Vivo. Traffic. 9, 1354-71.

Fernandez, J.J., Li, S., Crowther, R.A. (2008).  Image Restoration in Electron Cryotomography.- Towards Cellular Ultrastructure at Molecular Level. Innovation in Hybrid Intelligent Systems. 44, 345-352.

Fernandez, J.J., Li, S., Lucic, V.  (2008). Structure-Preserving Noise Reduction in Biological Imaging. Innovation in Hybrid Intelligent Systems. 44, 385-392.

Fernandez, J.J., Li, S., Lucic, V.  (2007).  Three-Dimensional Anisotropic Noise Reduction with Automated Parameter Tuning: Application to Electron Cryotomography. Curr. Topics in Artificial Intelligence 4788, 60-69.

Li, S., Sandercock, A.M., Conduit, P., Robinson, C.V., Williams, R.L., Kilmartin, J.V. (2006). Structural Role of Sfi1p-centrin Filaments in Budding Yeast Spindle Pole Body Duplication. J. Cell Biol. 173, 867-77.

Fernandez, J.J., Li, S., Crowther, R.A. (2006). CTF Determination and Correction in Electron Cryotomography. Ultramicroscopy 106, 587-96.

Fernandez, J.J., Li, S. (2005). Anisotropic nonlinear filtering of cellular structures in cryoelectron tomography. Computing in Science & Engineering 7, 54-61.

Fernandez, J.J., Li, S. (2003).  An Improved Algorithm for Anisotropic Nonlinear Diffusion for Denoising Cryo-tomograms.  J. Struct. Biol. 144, 152-61.