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Department of Chemistry & Biochemistry
The University of Texas at Austin
1 University Station A5300
Austin, TX 78712-0165





















Contact Information


Office: MBB: 2.148
Phone: 471-1514

Lab


Office:
Phone:
Fax: 232-3432

Rick Russell


rick_russell@mail.utexas.edu
Assistant Professor, Faculty


Research Group


Russell Lab

Education


BA, Earlham College, 1991
PhD, Johns Hopkins University, 1997

Affiliations


Institute for Cellular and Molecular Biology;

RNA-Protein Enzymes: Formation and Function


Some of nature's most complex and important enzyme machines are composed of RNA and protein. For these machines to function, each RNA and protein component must fold to its correct three-dimensional structure and all must assemble into a macromolecular complex. The goal of our research is to obtain a quantitative and rigorous molecular understanding of the assembly and functions of these remarkable enzymes.

Experimental systems
Initial projects are focused on two RNA-protein enzyme systems. The first is the complex formed between a group I RNA and a tRNA synthetase protein, which together are able to accelerate an RNA splicing reaction by a billion-fold. This "one RNA, one protein" enzyme provides a system that is fascinating, as it is a very efficient catalyst, and at the same time is amenable to detailed quantitative probing. The second system is the spliceosome, which is ubiquitous in eukaryotes and performs the essential task of removing introns from messenger RNAs. The spliceosome is composed of five RNAs and more than 50 proteins, which must assemble into a functional complex and perform a series of large-scale structural changes during each splicing reaction.

Approaches
The lab uses an arsenal of biochemical and biophysical approaches. Central among these is single-molecule fluorescence, which has unique power in dissecting complex molecular processes. Individual steps of a process often go undetected using conventional "bulk" approaches because, due to the stochastic nature of molecular events, intermediate forms resulting from completion of a reaction step do not accumulate to a significant fraction of the population. In contrast, with the observation of a single molecule or complex there is no need for averaging over a population so that, in principle, the multiple steps and pathways of complex molecular processes may be uncovered.

Representative Publications



Russell, R, Tijerina, P., Chadee, A.B., and Bhaskaran, H. "Deletion of the P5abc peripheral element accelerates early and late folding steps of the Tetrahymena group I ribozyme" Biochemistry 46 (2007): 4951-61.

Grohman, J.K., Del Campo, M., Bhaskaran, H., Tijerina, P., Lambowitz, A.M., and Russell, R. "Probing the mechanisms of DEAD-box proteins as general RNA chaperones: The C-terminal domain of CYT-19 mediates general recognition of RNA" Biochemistry 46 (2007): 3013-22.

Johnson, T.H., Tijerina, P., Chadee, A.B., Herschlag, D., and Russell, R. "Structural specificity conferred by a group I RNA peripheral element" Proc. Natl. Acad. Sci. U.S.A. 102 (2005): 10176-10181.

Lee, J.C., Gutell, R.R., Russell, R. "The UAA/GAN internal loop motif: A new RNA structural element that forms a cross-strand AAA stack and long-range tertiary interactions" J. Mol. Biol. 360 (2006): 978-988.

Russell, R., Das, R., Suh, H., Travers, K., Laederach, A., Engelhardt, M., and Herschlag, D. "The paradoxical behavior of a highly structured misfolded intermediate in RNA folding" J. Mol. Biol. 363 (2006): 531-544.

Tijerina, P., Bhaskaran, H., and Russell, R. "Non-specific binding to structured RNA and preferential unwinding of an exposed helix by the CYT-19 protein, a DEAD-box RNA chaperone" Proc. Natl. Acad. Sci. U.S.A. 103 (2006): 16698-16703.