Walter J. Chazin, Ph.D.
Chancellor's Professor of Medicine
Professor, Departments of Biochenistry and Chemistry
Director, Vanderbilt University Center for Structural Biology
Director, Molecular Biophysics Training Program
Vanderbilt University Medical Center
5140 MRB III, Suite 5140
Nashville, TN 37232
My research interests fall under the general theme of understanding the structural basis for recognition, biochemical function and biological specificity of proteins and nucleic acids. My background in chemistry frames the way I think, but the deciding factor for choosing problems is not the approach, but rather the biomedical problem.
My research interests fall under the general theme of understanding the structural basis for recognition, biochemical function and biological specificity of proteins and nucleic acids. My background in chemistry frames the way I think, but the deciding factor for choosing problems is not the approach, but rather the biomedical problem. Another key characteristic is tight coupling of our research to functional analysis. This strategy is by nature very collaborative and collegial, and has stimulated involvement in several multi-investigator research programs. Our structural biology research focuses on the cutting edge of the technology and its application to increasingly complex systems. A significant part of our research is now devoted to multi-protein complexes, with programs studying various aspects of genome maintenance ranging from DNA replication to damage response and repair.
- B.Sc. - Chemistry, 1975, McGill University, Montreal, Quebec, Canada
- Ph.D. - Chemistry, 1983, Concordia University, Montreal, Quebec, Canada
- Postdoc - Biophysics 1983-1985, E.T.H. Honggerberg, Zurich, Switzerland
- Postdoc - Structural Biology, 1986-1987, The Scripps Research Institute, La Jolla, CA
Structural Cell Biology: DNA replication, damage response and repair; ubiquitination; calcium signal transduction.
Research in my laboratory uses a multi-disciplinary, collaborative and structurally-oriented approach to address key problems in biology and medicine. At the molecular level, we study the structure and dynamics of proteins and their complexes with other proteins, nucleic acids and small molecule ligands. My independent career began as a biomolecular NMR spectroscopist, but has evolved to a point where I could be categorized as a structural biochemist. At the technical level, we now make use of many structural and biophysical techniques, including calorimetry, fluorescence spectroscopy, X-ray crystallography, X-ray/neutron scattering, cryo electron microscopy and computation. These studies are integrated with in vitro and cell-based biochemistry, in our own lab and by numerous collaborators at our institution, around the country and across the world. The following sections outline our three research programs.
I. The Structural Basis for Function of DNA Processing Machinery
One of the great scientific challenges today is to understand how proteins act together to perform the major processes in a cell such as DNA replication, all of which involve a sequence of multiple biochemical steps. Much of our work has revolved around human Replication Protein A (RPA), the major eukaryotic single-strand DNA (ssDNA) binding protein, which is essential for most DNA transactions in all cells. RPA is structurally very complex with three subunits containing eight different domains. It functions by constantly adjusting its binding of ssDNA and other proteins through structural changes within its domains as well as by altering the organization of its domains.
Our work has helped delineate the way in which RPA helps to orchestrate the intricate dance of proteins that is required to replicate DNA, respond when DNA is damaged, and repair the damage. Important insights have been obtained by identifying, and structurally characterizing, the interactions of RPA with specific proteins required for each of these processes. Recently, we have focused on the rearrangements in the global architecture of RPA, the mechanisms of binding and unbinding DNA, and how the binding of protein partners alter the landscape. As we have progressed, there has been an increasing need to determine structures of RPA binding partners. Current efforts center on human DNA primase, XPA and XPC. Together, these studies are laying the foundation to determine how mutations in the DNA processing proteins cause defects that lead to cancer and other diseases. Moreover, we are well invested into exploring translation of this knowledge into potential therapeutics by using fragment-based inhibitor discovery targeted to suppressing RPA-mediated recruitment of proteins to sites of DNA damage.
II. Structure and Function of U-box E3 Ubiquitin Ligases.
Covalent attachment of ubiquitin to a target protein serves as a cellular signal. For example, poly-ubiquitination of a target typically signals for degradation in the proteasome. Defects in this process are associated with cancer, for example a target can become overabundant if it is not degraded at a sufficient rate. The process of attaching ubquitin to a substrate protein involves a dynamic multi-protein machine comprised of E1, E2 and E3 enzymes. Our laboratory was the first to experimentally determine the structure of the U-box class of E3 ligases. Our studies of U-box proteins have focused on the mechanism of activation of the E2~ubiquitin conjugates, understanding how target proteins are recognized, and what factors control the type of ubiquitin chain attached. We are also investigating how the U-box E3 CHIP differentially regulates targets in the cell stress response.
III. Ca2+ Signal Transduction by EF-hand Proteins
Change in levels of calcium inside a cell is a common means for regulating biochemical signaling cascades and stimulating biomechanical actions. EF-hand calcium binding proteins play a central role in virt
- Mortensen, BL, Rathi, S, Chazin, WJ, Skaar, EP Acinetobacter baumannii response to host-mediated zinc limitation requires the transcriptional regulator Zur. J Bacteriol, 196(14), 2616-26, 2014.
- Chazin, Ede L, Reis, Rda R, Junior, WT, Moor, LF, Vasconcelos, TR An overview on the development of new potentially active camptothecin analogs against cancer. Mini Rev Med Chem, 14(12), 953-62, 2014.
- Frank, AO, Vangamudi, B, Feldkamp, MD, Souza-Fagundes, EM, Luzwick, JW, Cortez, D, Olejniczak, ET, Waterson, AG, Rossanese, OW, Chazin, WJ, Fesik, SW Discovery of a potent stapled helix peptide that binds to the 70N domain of replication protein A. J Med Chem, 57(6), 2455-61, 2014.
- Hwang, HS, Nitu, FR, Yang, Y, Walweel, K, Pereira, L, Johnson, CN, Faggioni, M, Chazin, WJ, Laver, D, George, AL, Cornea, RL, Bers, DM, Knollmann, BC Divergent regulation of ryanodine receptor 2 calcium release channels by arrhythmogenic human calmodulin missense mutants. Circ Res, 114(7), 1114-24, 2014.
- Vaithiyalingam, S, Arnett, DR, Aggarwal, A, Eichman, BF, Fanning, E, Chazin, WJ Insights into eukaryotic primer synthesis from structures of the p48 subunit of human DNA primase. J Mol Biol, 426(3), 558-69, 2014.
- Makita, N, Yagihara, N, Crotti, L, Johnson, CN, Beckmann, BM, Roh, MS, Shigemizu, D, Lichtner, P, Ishikawa, T, Aiba, T, Homfray, T, Behr, ER, Klug, D, Denjoy, I, Mastantuono, E, Theisen, D, Tsunoda, T, Satake, W, Toda, T, Nakagawa, H, Tsuji, Y, Tsuchiya, T, Yamamoto, H, Miyamoto, Y, Endo, N, Kimura, A, Ozaki, K, Motomura, H, Suda, K, Tanaka, T, Schwartz, PJ, Meitinger, T, K¿¿¿¿b, S, Guicheney, P, Shimizu, W, Bhuiyan, ZA, Watanabe, H, Chazin, WJ, George, AL Novel calmodulin mutations associated with congenital arrhythmia susceptibility. Circ Cardiovasc Genet, 7(4), 466-74, 2014.
- Shuck, SC, Wauchope, OR, Rose, KL, Kingsley, PJ, Rouzer, CA, Shell, SM, Sugitani, N, Chazin, WJ, Zagol-Ikapitte, I, Boutaud, O, Oates, JA, Galligan, JJ, Beavers, WN, Marnett, LJ Protein modification by adenine propenal. Chem Res Toxicol, 27(10), 1732-42, 2014.
- Sugitani, N, Shell, SM, Soss, SE, Chazin, WJ Redefining the DNA-binding domain of human XPA. J Am Chem Soc, 136(31), 10830-3, 2014.
- Feldkamp, MD, Mason, AC, Eichman, BF, Chazin, WJ Structural analysis of replication protein A recruitment of the DNA damage response protein SMARCAL1. Biochemistry, 53(18), 3052-61, 2014.
- Gaddy, JA, Radin, JN, Loh, JT, Piazuelo, MB, Kehl-Fie, TE, Delgado, AG, Ilca, FT, Peek, RM, Cover, TL, Chazin, WJ, Skaar, EP, Scott Algood, HM The host protein calprotectin modulates the Helicobacter pylori cag type IV secretion system via zinc sequestration. PLoS Pathog, 10(10), e1004450, 2014.
- Brosey, CA, Yan, C, Tsutakawa, SE, Heller, WT, Rambo, RP, Tainer, JA, Ivanov, I, Chazin, WJ A new structural framework for integrating replication protein A into DNA processing machinery. Nucleic Acids Res, 41(4), 2313-27, 2013.
- Soss, SE, Klevit, RE, Chazin, WJ Activation of UbcH5c~Ub is the result of a shift in interdomain motions of the conjugate bound to U-box E3 ligase E4B. Biochemistry, 52(17), 2991-9, 2013.
- Crotti, L, Johnson, CN, Graf, E, De Ferrari, GM, Cuneo, BF, Ovadia, M, Papagiannis, J, Feldkamp, MD, Rathi, SG, Kunic, JD, Pedrazzini, M, Wieland, T, Lichtner, P, Beckmann, BM, Clark, T, Shaffer, C, Benson, DW, K¿¿¿¿b, S, Meitinger, T, Strom, TM, Chazin, WJ, Schwartz, PJ, George, AL Calmodulin mutations associated with recurrent cardiac arrest in infants. Circulation, 127(9), 1009-17, 2013.
- Patrone, JD, Kennedy, JP, Frank, AO, Feldkamp, MD, Vangamudi, B, Pelz, NF, Rossanese, OW, Waterson, AG, Chazin, WJ, Fesik, SW Discovery of Protein-Protein Interaction Inhibitors of Replication Protein A. ACS Med Chem Lett, 4(7), 601-605, 2013.
- Frank, AO, Feldkamp, MD, Kennedy, JP, Waterson, AG, Pelz, NF, Patrone, JD, Vangamudi, B, Camper, DV, Rossanese, OW, Chazin, WJ, Fesik, SW Discovery of a potent inhibitor of replication protein a protein-protein interactions using a fragment-linking approach. J Med Chem, 56(22), 9242-50, 2013.
- Wells, CE, Bhaskara, S, Stengel, KR, Zhao, Y, Sirbu, B, Chagot, B, Cortez, D, Khabele, D, Chazin, WJ, Cooper, A, Jacques, V, Rusche, J, Eischen, CM, McGirt, LY, Hiebert, SW Inhibition of histone deacetylase 3 causes replication stress in cutaneous T cell lymphoma. PLoS One, 8(7), e68915, 2013.
- Kehl-Fie, TE, Zhang, Y, Moore, JL, Farrand, AJ, Hood, MI, Rathi, S, Chazin, WJ, Caprioli, RM, Skaar, EP MntABC and MntH contribute to systemic Staphylococcus aureus infection by competing with calprotectin for nutrient manganese. Infect Immun, 81(9), 3395-405, 2013.
- Damo, SM, Kehl-Fie, TE, Sugitani, N, Holt, ME, Rathi, S, Murphy, WJ, Zhang, Y, Betz, C, Hench, L, Fritz, G, Skaar, EP, Chazin, WJ Molecular basis for manganese sequestration by calprotectin and roles in the innate immune response to invading bacterial pathogens. Proc Natl Acad Sci U S A, 110(10), 3841-6, 2013.
- Damo, SM, Feldkamp, MD, Chagot, B, Chazin, WJ NMR studies of the interaction of calmodulin with IQ motif peptides. Methods Mol Biol, 963173-86, 2013.
- Xu, D, Young, JH, Krahn, JM, Song, D, Corbett, KD, Chazin, WJ, Pedersen, LC, Esko, JD Stable RAGE-heparan sulfate complexes are essential for signal transduction. ACS Chem Biol, 8(7), 1611-20, 2013.
- Feldkamp, MD, Frank, AO, Kennedy, JP, Patrone, JD, Vangamudi, B, Waterson, AG, Fesik, SW, Chazin, WJ Surface reengineering of RPA70N enables cocrystallization with an inhibitor of the replication protein A interaction motif of ATR interacting protein. Biochemistry, 52(37), 6515-24, 2013.
- Shell, SM, Hawkins, EK, Tsai, MS, Hlaing, AS, Rizzo, CJ, Chazin, WJ Xeroderma pigmentosum complementation group C protein (XPC) serves as a general sensor of damaged DNA. DNA Repair (Amst), 12(11), 947-53, 2013.
- Stork, M, Grijpstra, J, Bos, MP, Ma¿¿as Torres, C, Devos, N, Poolman, JT, Chazin, WJ, Tommassen, J Zinc piracy as a mechanism of Neisseria meningitidis for evasion of nutritional immunity. PLoS Pathog, 9(10), e1003733, 2013.
- Hood, MI, Mortensen, BL, Moore, JL, Zhang, Y, Kehl-Fie, TE, Sugitani, N, Chazin, WJ, Caprioli, RM, Skaar, EP Identification of an Acinetobacter baumannii zinc acquisition system that facilitates resistance to calprotectin-mediated zinc sequestration. PLoS Pathog, 8(12), e1003068, 2012.
- Brosey, CA, Tsutakawa, SE, Chazin, WJ Sample preparation methods to analyze DNA-induced structural changes in replication protein A. Methods Mol Biol, 922101-22, 2012.
- Chazin, WJ Evolution of the NIGMS Protein Structure Initiative. Structure, 16(1), 12-4, 2008.
- Corbin, BD, Seeley, EH, Raab, A, Feldmann, J, Miller, MR, Torres, VJ, Anderson, KL, Dattilo, BM, Dunman, PM, Gerads, R, Caprioli, RM, Nacken, W, Chazin, WJ, Skaar, EP Metal chelation and inhibition of bacterial growth in tissue abscesses. Science, 319(5865), 962-5, 2008.
- Weiner, BE, Huang, H, Dattilo, BM, Nilges, MJ, Fanning, E, Chazin, WJ An Iron-Sulfur Cluster in the C-terminal Domain of the p58 Subunit of Human DNA Primase. J Biol Chem, 282(46), 33444-51, 2007.
- Ball, HL, Ehrhardt, MR, Mordes, DA, Glick, GG, Chazin, WJ, Cortez, D Function of a Conserved Checkpoint Recruitment Domain in ATRIP Proteins. Mol Cell Biol, 2007.
- Dattilo, BM, Fritz, G, Leclerc, E, Kooi, CW, Heizmann, CW, Chazin, WJ The extracellular region of the receptor for advanced glycation end products is composed of two independent structural units. Biochemistry, 46(23), 6957-70, 2007.
- Chazin, WJ The impact of X-ray crystallography and NMR on intracellular calcium signal transduction by EF-hand proteins: crossing the threshold from structure to biology and medicine. Sci STKE, 2007(388), pe27, 2007.
- Bunick, CG, Miller, MR, Fuller, BE, Fanning, E, Chazin, WJ Biochemical and structural domain analysis of xeroderma pigmentosum complementation group C protein. Biochemistry, 45(50), 14965-79, 2006.
- Shah, VN, Wingo, TL, Weiss, KL, Williams, CK, Balser, JR, Chazin, WJ Calcium-dependent regulation of the voltage-gated sodium channel hH1: Intrinsic and extrinsic sensors use a common molecular switch. Proc Natl Acad Sci U S A, 2006.
- Johnson, E, Chazin, WJ, Rance, M Effects of calcium binding on the side-chain methyl dynamics of calbindin D9k: a 2H NMR relaxation study. J Mol Biol, 357(4), 1237-52, 2006.
- Jiang, X, Klimovich, V, Arunkumar, AI, Hysinger, EB, Wang, Y, Ott, RD, Guler, GD, Weiner, B, Chazin, WJ, Fanning, E Structural mechanism of RPA loading on DNA during activation of a simple pre-replication complex. EMBO J, 25(23), 5516-26, 2006.
- Sheehan, JH, Bunick, CG, Hu, H, Fagan, PA, Meyn, SM, Chazin, WJ Structure of the N-terminal calcium sensor domain of centrin reveals the biochemical basis for domain-specific function. J Biol Chem, 281(5), 2876-81, 2006.
- Vander Kooi, CW, Ohi, MD, Rosenberg, JA, Oldham, ML, Newcomer, ME, Gould, KL, Chazin, WJ The Prp19 U-box crystal structure suggests a common dimeric architecture for a class of oligomeric E3 ubiquitin ligases. Biochemistry, 45(1), 121-30, 2006.
- Sunahori, K, Yamamura, M, Yamana, J, Takasugi, K, Kawashima, M, Yamamoto, H, Chazin, WJ, Nakatani, Y, Yui, S, Makino, H The S100A8/A9 heterodimer amplifies proinflammatory cytokine production by macrophages via activation of nuclear factor kappa B and p38 mitogen-activated protein kinase in rheumatoid arthritis. Arthritis Res Ther, 8(3), R69, 2006.
- Meyn, SM, Seda, C, Campbell, M, Weiss, KL, Hu, H, Pastrana-Rios, B, Chazin, WJ The biochemical effect of Ser167 phosphorylation on Chlamydomonas reinhardtii centrin. Biochem Biophys Res Commun, 342(1), 342-8, 2006.
- Malmendal, A, Vander Kooi, CW, Nielsen, NC, Chazin, WJ Calcium-Modulated S100 Protein-Phospholipid Interactions. An NMR Study of Calbindin D(9k) and DPC. Biochemistry, 44(17), 6502-6512, 2005.
- Arunkumar, AI, Klimovich, V, Jiang, X, Ott, RD, Mizoue, L, Fanning, E, Chazin, WJ Insights into hRPA32 C-terminal domain-mediated assembly of the simian virus 40 replisome. Nat Struct Mol Biol, 12(4), 332-9, 2005.
- Nakatani, Y, Yamazaki, M, Chazin, WJ, Yui, S Regulation of S100A8/A9 (calprotectin) binding to tumor cells by zinc ion and its implication for apoptosis-inducing activity. Mediators Inflamm, 2005(5), 280-92, 2005.
- Bhattacharya, S, Lee, YT, Michowski, W, Jastrzebska, B, Filipek, A, Kuznicki, J, Chazin, WJ The modular structure of SIP facilitates its role in stabilizing multiprotein assemblies. Biochemistry, 44(27), 9462-71, 2005.
- Wingo, Tammy L, Shah, Vikas N, Anderson, Mark E, Lybrand, Terry P, Chazin, Walter J, Balser, Jeffrey R An EF-hand in the sodium channel couples intracellular calcium to cardiac excitability. Nat Struct Mol Biol, 11(3), 219-25, 2004.
- Bunick, Christopher G, Nelson, Melanie R, Mangahas, Sheryll, Hunter, Michael J, Sheehan, Jonathan H, Mizoue, Laura S, Bunick, Gerard J, Chazin, Walter J Designing sequence to control protein function in an EF-hand protein. J Am Chem Soc, 126(19), 5990-8, 2004.
- Christodoulou, John, Malmendal, Anders, Harper, Jeffrey F, Chazin, Walter J Evidence for differing roles for each lobe of the calmodulin-like domain in a calcium-dependent protein kinase. J Biol Chem, 279(28), 29092-100, 2004.
- Lee, Young-Tae, Jacob, Jaison, Michowski, Wojciech, Nowotny, Marcin, Kuznicki, Jacek, Chazin, Walter J Human Sgt1 binds HSP90 through the CHORD-Sgt1 domain and not the tetratricopeptide repeat domain. J Biol Chem, 279(16), 16511-7, 2004.
- Stauffer, Melissa E, Chazin, Walter J Physical interaction between replication protein A and Rad51 promotes exchange on single-stranded DNA. J Biol Chem, 279(24), 25638-45, 2004.
- Stauffer, Melissa E, Chazin, Walter J Structural mechanisms of DNA replication, repair, and recombination. J Biol Chem, 279(30), 30915-8, 2004.
- Bhattacharya, Shibani, Bunick, Christopher G, Chazin, Walter J Target selectivity in EF-hand calcium binding proteins. Biochim Biophys Acta, 1742(1-3), 69-79, 2004.
- Hu, Haitao, Sheehan, Jonathan H, Chazin, Walter J The mode of action of centrin. Binding of Ca2+ and a peptide fragment of Kar1p to the C-terminal domain. J Biol Chem, 279(49), 50895-903, 2004.
- Arunkumar, AI, Stauffer, ME, Bochkareva, E, Bochkarev, A, Chazin, WJ Independent and coordinated functions of replication protein A tandem high affinity single-stranded DNA binding domains. J Biol Chem, 278(42), 41077-82, 2003.
- Ohi, Melanie D, Vander Kooi, Craig W, Rosenberg, Joshua A, Chazin, Walter J, Gould, Kathleen L Structural insights into the U-box, a domain associated with multi-ubiquitination. Nat Struct Biol, 10250-5, 2003.
- Bhattacharya, S, Large, E, Heizmann, CW, Hemmings, B, Chazin, WJ Structure of the Ca2+/S100B/NDR kinase peptide complex: insights into S100 target specificity and activation of the kinase. Biochemistry, 42(49), 14416-26, 2003.
- Hu, H, Chazin, WJ Unique features in the C-terminal domain provide caltractin with target specificity. J Mol Biol, 330(3), 473-84, 2003.
- MÃ¤ler, L, Blankenship, J, Rance, M, Chazin, W J Site-site communication in the EF-hand Ca2+-binding protein calbindin D9k. Nat Struct Biol, 7(3), 245-50, 2000.
- Mer, G, Bochkarev, A, Gupta, R, Bochkareva, E, Frappier, L, Ingles, C J, Edwards, A M, Chazin, W J Structural basis for the recognition of DNA repair proteins UNG2, XPA, and RAD52 by replication factor RPA. Cell, 103(3), 449-56, 2000.
- Smith, JA, Bifulco, G, Case, DA, Boger, DL, Gomez-Paloma, L, Chazin, WJ The structural basis for in situ activation of DNA alkylation by duocarmycin SA. J Mol Biol, 300(5), 1195-204, 2000.
- Botuyan, M V, Koth, C M, Mer, G, Chakrabartty, A, Conaway, J W, Conaway, R C, Edwards, A M, Arrowsmith, C H, Chazin, W J Binding of elongin A or a von Hippel-Lindau peptide stabilizes the structure of yeast elongin C. Proc Natl Acad Sci U S A, 96(16), 9033-8, 1999.
- Miick, S M, Fee, R S, Millar, D P, Chazin, W J Crossover isomer bias is the primary sequence-dependent property of immobilized Holliday junctions. Proc Natl Acad Sci U S A, 94(17), 9080-4, 1997.
- Linse, S, JÃ¶nsson, B, Chazin, W J The effect of protein concentration on ion binding. Proc Natl Acad Sci U S A, 92(11), 4748-52, 1995.
- Potts, B C, Smith, J, Akke, M, Macke, T J, Okazaki, K, Hidaka, H, Case, D A, Chazin, W J The structure of calcyclin reveals a novel homodimeric fold for S100 Ca(2+)-binding proteins. Nat Struct Biol, 2(9), 790-6, 1995.
- Skelton, N J, KÃ¶rdel, J, Akke, M, ForsÃ©n, S, Chazin, W J Signal transduction versus buffering activity in Ca(2+)-binding proteins. Nat Struct Biol, 1(4), 239-45, 1994.