James R. Williamson is a biophysicist known for his work on the structural biology of RNA-protein complexes, including key regulatory complexes from HIV and bacterial ribosome assembly intermediates. He applies a broad range of biophysical techniques, including NMR spectroscopy, X-tray crystallography, electron microscopy, single molecule fluorescence, and mass spectrometry, to understand the conformational changes and dynamics for ribonucleoprotein complexes. Williamson grew up in New England and attended Mount Union College in Alliance OH, earning a B.S. in Chemistry in 1981. He earned a Ph.D. in Chemistry from Stanford University in 1988, and did postdoctoral work at the University of Colorado, prior to joining the faculty in the Chemistry Department at MIT in 1990. Williamson moved to Scripps Research in 1998 as Professor, and has served as Dean of Graduate Studies there, and in 2017 was appointed as the Executive Vice President of Research and Academic Affairs.

Research Interests

James Williamson's laboratory studies the interaction between RNAs and proteins and the folding of large cellular RNAs. They have used structural biology methods to determine the structures of key regulatory RNA-protein complexes, and they were among the first labs to develop quantitative methods for studying the folding kinetics of RNAs. They have a long-standing interest in understanding the complex process of ribosome assembly in bacteria, which accounts for almost a third of the energy budget for a rapidly growing cell. Using a broad array of biophysical techniques, most recently cryo-electron microscopy, they have characterized the intermediates along the pathway of cotranscriptional 50S ribosome assembly, identifying cooperative folding blocks and parallel pathways that ultimately converge on the active ribosomal subunit. This work provides molecular understanding of assembly that serve as a paradigm for formation of the many ribonucleoprotein complexes in cells that carry out diverse functions.

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Primary Section

Section 29: Biophysics and Computational Biology

Secondary Section

Section 21: Biochemistry