Cell Motility and Cytoskeleton
Work done by muscle and non-muscle cells requires the transduction of chemical into mechanical energy. This function is carried out by a cellular contractile apparatus which contains actin, tubulin, and a family of motor proteins. The interactions between these proteins and the changes in their structure constitute the molecular basis for force generation and motility in muscle and non-muscle cells. Our goal of elucidating the mechanism of contractile processes is pursued at two levels. At the molecular level, we are concerned with the structural and dynamic properties of the contractile proteins. We explore structure-function relationships in actin, myosin and other proteins by biochemical, biophysical, immunochemical, mutational, and in the vitro motility and force measurements. Intermediate steps in the contractile process are probed with the help of nucleotide analogues, specific antibodies, synthetic peptides, and appropriate mutants of the key proteins. The aim of these studies is to obtain a structural description of the mechanism of motion and force generation by motor proteins. At the cellular level, we study the function, interactions, and structural transitions of the assembled protein systems.
Many cellular processes depend on rapid remodeling of cytoskeleton and actin filaments. The biological function of these filaments is frequently linked to the regulation of their assembly, bundling, branching, and treadmilling. Our interest is focused on the interaction of actin binding proteins with actin monomers and filaments. The mechanisms of the assembly reactions and the structural changes which govern the remodeling of filaments are studied by biophysical, biochemical, and electron microscopy methods. To understand the regulation of actin assembly by other proteins, macromolecular contact sites are investigated by a wide spectrum of experimental techniques.
| Representative Publications |
Publications from Reisler Lab (1998-2002)
Publications from Reisler Lab (2003-present)
1. Pavlov, D., Gerson, J. H., Yu, T., Tobacman, L. S., Homsher, E., and Reisler, E. The regulation of subtilisin-cleaved actin by tropomyosin/troponin. J. Biol. Chem. 278, 5517-5522 (2003).
2. Nitao, L. K., Ogarzalek Loo, R. R., O'Neal-Hennessey, E., Loo, J. A., Szent-Gyorgyi, A. G., and Reisler, E. Conformation and dynamics of the SH1-SH2 helix in scallop myosin. Biochemistry 42, 7663-7674 (2003).
3. Kudryashov, D.S., and Reisler, E. Solution properties of tetramethylrhodamine-modified G-actin. Biophys. J. 85, 2466-2475 (2003).
4. Guan, J.-Q., Almo, S.A., Reisler, E., and Chance. M.R. Structural reorganization of proteins revealed by radiolysis and mass spectrometry: G-actin solution structure is divalent cation dependent. Biochemistry 42, 11992-12000 (2003).
5. Galkin, V.E., Orlova, A., VanLoock, M.S., Shvetsov, A. Reisler, E., and Egelman, E.H. ADF/cofilin use intrinsic mode of F-actin instability to disrupt actin filaments. J. Cell Biol. 163, 10057-1066 (2003).
6. Bobkov, A.A., Muhlrad, A., Shvetsov, A., Benchaar, S., Scoville, D., Almo, S.C., and Reisler, E. Cofilin (ADF) affects lateral contacts in F-actin. J. Mol. Biol. 337, 93-104 (2004).
7. Kudryashov, D.S., Phillips, M., and Reisler, E. Formation and destabilization of actin filaments with tetramethylrhodamine-modified actin. Biophys. J. 87, 1136-1145 (2004).
8. Muhlrad, A., Kudryashov, D., Peyser, Y.M., Bobkov, A.A., Almo, S.C., and Reisler, E. Cofilin-induced conformational changes in F-actin expose subdomain 2 to proteolysis. J. Mol. Biol. 342, 1559-1567 (2004).
9. Orlova, A., Shvetsov, A., Galkin, V.E., Kudryashov, D.S., Rubenstein, P.A., Egelman, E.H., and Reisler, E. Actin destabilizing factors disrupt filaments by means of a time reversal of polymerizations. Proc. Natl. Acad. Sci. USA 101, 17664-17668 (2004).
10. Guan, J.-Q., Takamoto, K., Almo, S.C., Reisler, E., and Chance, M.C. Structure and dynamics of the Actin Filament. Biochemistry 44, 3166-3175 (2005).
11. Kudryashov, D.S., Sawaya, M.R., Adisetiyo, H., Norcoss, T., Hegyi, G., Reisler, E., and Yeates, T.O. The crystal structure of a cross-linked actin dimer suggests a detailed molecular interface in F-actin. Proc. Natl. Acad. Sci. USA 102, 13105-13110 (2005).
12. Shvetsov, A., Stamm, J.D., Phillips, M., Warshaviak, D., Altenbach, C., Rubenstein, P.A., Hideg, K., Hubbell, W.L., and Reisler, E. Conformational dynamics of loop 262-274 in G- and F-actin. Biochemistry 45, 6541-6549 (2006).
13. Cordero, C.L., Kudryashov, D.S., Reisler, E., and Satchell, K.J. The actin cross-linking domain of the vibrio cholerae RTX toxin directly catalyzes the covalent cross-linking of actin. J. Biol. Chem. 281, 32366-32374 (2006).
14. Bobkov, A.A., Muhrda, A., Pavlov, D.A., Kokabi, K., Yilmaz, A., and Reisler, E. Cooperative effects of cofilin (ADF) on actin structure suggest allosteric mechanism of cofilin function. J. Mol. Biol. 356, 325-334 (2006).
15. Kudryashov, D.S., Galkin, V.E., Orlova, A., Phan, M., Egelman, E.H., and Reisler, E. Cofilin cross-bridges adjacent actin protomers and replaces part of the longitudinal F-actin interface. J. Mol. Biol. 358, 785-797 (2006).
16. Pavlov, D., Muhlrad, A., Cooper, J., Wear, M., and Reisler, E. Severing of F-actin by yeast cofilin is pH-independent. Cell Motility and the Cytoskeleton 63, 533-542 (2006).
17. Muhlrad, A., Ringel, I., Pavlov, D., Peyser, Y.M., and Reisler, E. Antagonistic effects of coofilin , beryllium fluoride complex and phalloidin on subdomain 2 and nucleotide-binding cleft in F-actin. Biophys J. 91, 4490-9 (2006).
18. Muhlrad, A., Pavlov, D., Peyser, Y.M., and Reisler, E. Inorganic phosphate regulates the binding of cofilin to actin filaments. FEBS J. 273, 1488-1496 (2006).
19. Sowa, G.Z, Cannell, D.S, Liu, A.J, and Reisler, E. Polyamine-Induced Bundling of F-Actin. J. Phys. Chem. B, 110, 22279-22284 (2006).
20. Scoville, D, Stamm, J.D, Toledo-Warshaviak, D, Altenbach, C, Phillips, M, Shvetsov, A, Rubenstein, P.A, Hubbell, W.L, and Reisler, E. Hydrophobic Loop Dynamics and Actin Filament Stability. Biochemistry 45, 13576-13584 (2006).
21. Benchaar SA, Xie Y, Phillips M, Loo RR, Galkin VE, Orlova A, Thevis M, Muhlrad A, Almo SC, Loo JA, Egelman EH, Reisler E. Mapping the Interaction of Cofilin with Subdomain 2 on Actin. Biochemistry 46, 225-233 (2007).
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