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Dr. Auron received his Ph.D. in Biochemistry from the Pennsylvania State University in 1980, studying prokaryotic ribosome structure and function. He then conducted postdoctoral studies at The Massachusetts Institute of Technology using chemical and enzymatic techniques in concert with computer algorithmic model building and X-ray crystal structure data to predict the structure of small (tRNA) and large (rRNA and mRNA) ribonucleic acid molecules in solution.
In 1983 Dr. Auron accepted a faculty position as an Assistant Professor at Tufts University School of Medicine in Boston, while maintaining a joint visiting faculty position and laboratory at MIT in the joint Harvard-MIT division of Health Sciences and Technology. It was at this time that he initiated seminal studies leading to the characterization of interleukin 1 beta and its gene structure and regulation.
In 1989, Dr. Auron joined the faculty in the Department of Pathology at Harvard Medical School, and was promoted to Associate Professor in 1993. Dr. Auron joined the Department of Molecular Genetics and Biochemistry at the University of Pittsburgh School of Medicine in 2002.
In August 2006, Dr. Auron accepted an appointment to the Department of Biological Sciences at Duquesne, where he presently serves as chairman.
Dr. Auron's interests in the relationship between molecular structure and function have guided his work. Most studies have focused on mechanistic approaches that often rely upon correlation with known high-resolution structures and molecular model building.
Dr. Auron has also contributed to the bioinformatics field, having published several papers dealing with nucleic acid analysis software and hardware. Two commercial software packages aimed at molecular biology users have resulted from his efforts.
In March, 1982, Dr. Auron was a member of the group that submitted the original contract application proposal for the GenBank database which resulted in the establishment of that famous repository. Finally, Dr. Auron was involved in high-profile landmark litigation in which he defended the sanctity of confidentiality during the peer review process ( Science 273:1162-4, 1996; Nature 384:1-4, 1996; Biotechnology 14:14, 1996; Nature Biotechnology 14:275-9, 1996; The Washington Post April 19, 1996, p.D1); and JAMA - Third International Congress on Biomedical Peer Review and Global Communications Sept. 18-20, 1997.
The research focuses on molecular mechanisms of cytokine gene regulation. One of these cytokines is interleukin 1 (IL-1) which influences genes expressing various proteins that can modulate the level of acute and chronic inflammation and thus mediate subsequent fever and tissue destruction. In 1984, Dr. Auron was involved in the original cloning and characterization of IL-1beta cDNA. This was followed by the isolation and sequencing of the corresponding IL1B gene locus. The induced IL1B gene product is involved in inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, arteriosclerosis, bacterial sepsis and infection by certain viruses.
The laboratory has placed emphasis on the detailed molecular processes and structures involved both in receptor signal transduction and gene transcription in normal cells and those expressing proinflammatory proteins derived from cytomegalovirus infection. Attention has also been paid to cell-type-specific expression. As a result, Dr. Auron and his collaborators have determined that the monomyeloid-specific ETS domain transcription factor, Spi-1/PU.1, is required for vigorous expression of the IL1B gene. They have also determined that physical interaction between Spi-1 and GATA-family proteins is responsible for a mutual inhibition that is critical for stem cell commitment to erythroid vs. mono-myeloid lineage development in hematopoiesis. Spi-1, which is essential for monocyte and osteoclast development, binds to the IL1B gene and couples the gene induction signal, found in a distinct location approximately 3kbp upstream from the transcription start site, directly to the general transcription machinery. The Spi-1/PU.1 factor is also targeted during human cytomegalovirus (HCMV) infection and mediates viral-induction of IL1B by eliminating the requirement for the exogenous activation signal via one specific HCMV protein (IE2, immediate early protein 2). Research focusing on receptor signal transduction has resulted in the discovery that the IL-1 receptor-activated intracellular signal transducer called TRAF6 functions through at least two distinct pathways that result in differential activation of Rel/NF-kB transcription factor family members. This may be responsible for some of the known subtleties of the inflammatory response.
Methods being employed by the laboratory include:
1) identifying protein domains capable of supporting various protein-protein interactions;
2) examining these domains by computer molecular modeling in order to design dominant-negative mutations and small molecule inhibitors;
3) determining whether the inhibitors can function in vivo and serve as potential therapeutics; and
4) single-cell techniques involving microscopic examination of protein domains fused to full-length and split-GFP (BiFC, bimolecular fluorescence complementation) probes in living cells. Studies are aimed at examining sub-cellular localization and protein-protein interaction for wild-type and modified proteins such as transcription factors, signaling molecules, and kinases involved in IL-1 receptor signal transduction.
The gene coding for human interleukin 1 beta (IL1B) is expressed most vigorously in monocytes activated via Toll-like receptors, such as TLR4 which responds to lipopolysaccharide (LPS). This signal transduction event, which is mediated by the cytoplasmic mediator TRAF6, activates latent transcription factors which target specific regions of the IL1B gene, resulting in immediate-early transcription. Ongoing research is aimed at identifying relevant factors and genomic functional structure using in vivo approaches such as chromatin immunoprecipitation (ChIP) and chromatin conformational capture (3C) on cell lines and primary cells. One goal is to understand the relative importance of distinct factors and design specific inhibitors that could function as novel anti-inflammatory drugs.
We have been very interested in the process by which DNA-binding transcription factors can induce gene expression in the absence of direct DNA binding. We have referred to this process as protein tethered transactivation (PTT). In PTT one transcription factor can bind a DNA target site and in-turn recruit a second DNA-binding factor in the absence of a cognate site via a protein-protein interaction. The recruited factor can then increase the level of transcription by serving as a cofactor, much like CEBP/p300 which cannot directly bind DNA. We have demonstrated at least two such occurrences of this phenomenon on the IL1B gene (involving DNA-bound Spi-1 interacting with either HCMV IE2 or with C/EBPbeta) and one on the gene coding for IL-8 (involving DNA-bound NF-kB p65 interacting with non-tyrosine phosphorylated Stat3). We have discovered other such interactions, and would like to determine how common PTT is throughout the genome.
TRAF6 is a downstream signaling molecule used in common by the entire family of Toll-IL1/IL18 receptors (TIRs). Effort is focused on examining the sub-cellular localization and protein interaction partners of TRAF6 by the use of fluorescent probes that are activated only in the presence of a cognate interaction partner. These probes use the principle of bimolecular fluorescence complementation (BiFC) in which two inactive fluorescent protein fragments (split-GFP) are activated upon association mediated by tethered interacting proteins. This approach permits the observation of protein-protein interaction in living cells following receptor-mediated activation. We have also used full-length GFP probes fused to various plextrin homology (PH) domains (e.g., that of Akt and Tec kinases) to monitor the generation of phosphoinositides within cell membranes following over-expression of various activating molecules, including wild-type and mutated TRAF molecules.
Human cytomegalovirus (HCMV) is a pro-inflammatory virus that induces the IL1B gene. Studies are aimed at understanding the distinct roles played by two different HCMV-derived proinflammatory stimuli. Exogenous stimuli (such as envelope glycoprotein B activation via TLR2) and endogenous stimuli (such as IE2 activation of host Spi-1/PU.1) are being examined in order to determine the relative importance of each pathway.
. Auron, P.E., Webb, A.C., Rosenwasser, L.J., Mucci, S.F., Rich, A., Wolff, S.M., and Dinarello, C.A. Nucleotide sequence of human monocyte interleukin-1 precursor cDNA. Proc. Natl. Acad. Sci., USA 81:7907-7911, 1984.
. Clark BD, Collins KL, Gandy MS, Webb AC, Auron PE. Genomic sequence for human prointerleukin 1 beta: possible evolution from a reverse transcribed prointerleukin 1 alpha gene. Nucleic Acids Res. 14:7897-914, 1986.
. Galson, D.L., Hensold, J.O., Bishop, T.R., Schalling, M., D'Andrea, A.D., Jones, C., Auron, P.E., and Housman, D.E. Mouse beta-globin DNA-binding protein B1 is identical to a proto-oncogene, the transcription factor Spi-1/PU.1, and is restricted in expression to hematopoietic cells and the testis. Mol. Cell. Biol. 13: 2929-2941, 1993.
. Tsukada, J., Saito, K., Waterman, W.R., Webb, A.C., and Auron, P.E. Transcription factors NF-IL6 and CREB recognize a common essential site in the human prointerleukin 1beta gene. Mol. Cell. Biol. 14: 7285-7297, 1994.
. Kominato, Y., Galson, D.L., Waterman, W.R., Webb, A.C., and Auron, P.E. Monocyte expression of the human prointerleukin 1beta gene (IL1B) is dependent upon promoter sequences which bind the hematopoietic transcription factor Spi-1/Pu.1. Mol. Cell. Biol. 15:58-68, 1995.
. Tsukada, J., Waterman, W.R., Koyama, Y., Webb, A.C., and Auron, P.E. A novel STAT-like factor mediates lipopolysaccharide, interleukin 1 (IL-1), and IL-6 signaling and recognizes a gamma interferon activation site-like element in the IL1B gene. Mol. Cell. Biol. 16: 2183-2194, 1996.
. Marmiroli, S., Bavelloni, A., Faenza, I., Sirri, A., Ognibene, A., Cenni, V., Tsukada, J., Koyama, Y., Ruzzene, M., Ferri, A., Auron, P.E., Toker, A., Maraldi, N.M. Phospatidylinositol 3-kinase is recruited to a specific site in the activated IL-1 receptor I. FEBBS Lett. 438: 49-54, 1998.
. Wara-aswapati, N., Yang, Z., Waterman, W.R., Koyama, Y., Tetradis, S., Choy, B.K., Webb, A.C., and Auron, P.E. Cytomegalovirus IE2 protein stimulates Interleukin 1beta gene transcription via tethering to Spi-1/PU.1. Mol. Cell. Biol. 19: 6803-6814, 1999.
. Yang, Z., Wara-aswapati, N., Chen, C., Tsukada, J., Auron, P.E. NF-IL6 (C/EBPbeta) vigorously activates IL1B expression via a Spi-1 (PU.1) protein-protein tether. J. Biol. Chem. 275: 21272-21277, 2000.
. Asea, A., Rehli, M., Kabingu, E., Boch, J.A., Bare, O., Auron, P.E., Stevenson, M.A., and Calderwood, S.K. Novel signal transduction pathway utilized by extracellular HSP70: role of toll-like receptor (TLR) 2 and TLR4. J. Biol. Chem. 277:15028-34, 2002.
. Yoshida Y, Kumar A, Koyama Y, Peng H, Arman A, Boch JA, Auron PE. Interleukin 1 activates STAT3/nuclear factor-kappaB cross-talk via a unique TRAF6- and p65-dependent mechanism. J. Biol. Chem. 279:1768-76, 2004.
. Listman, J.A., Wara-aswapati, N., Race, J.E., Blystone, L.W., Walker-Kopp, N., Yang, Z., and Auron, P.E. Conserved ETS domain arginines mediate DNA binding, nuclear localization and a novel mode of bZIP interaction. J. Biol. Chem. 280: 41421-8, 2005.
. Waterman, W.R., Xu, L.L., Tetradis, S., Motyckova, G., Tsukada, J., Saito, K., Webb, A.C., Robinson, D.R., and Auron, P.E. Glucocorticoid inhibits the human pro-interleukin 1beta gene (IL1B) by decreasing DNA binding of transactivators to the signal-responsive enhancer. Molec. Immunol. 43:773-82, 2006.
. Wang, K.Z.Q., Wara-aswapati, N., Boch, J.A., Galson, D.L., and Auron, P.E. TRAF6 Activation of PI3 kinase-dependent cytoskeletal changes is cooperative with Ras and mediated by an interaction with cytoplasmic c-Src. J. Cell Sci. 119: 1579-91, 2006.
Ectopic Expression of TRAF6 Induces Changes in Cell Morphology . For details see: Wang, K.Z.Q. et al . J. Cell Sci. 119: 1579-91, 2006.
Electrostatic Fields Surrounding Leucine Zippers May Dictate Interactions With Other Proteins. For details see: Listman, J.A. et al . J. Biol. Chem. 280: 41421-8, 2005.
PubMed Publications
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E-mail: auronp@duq.edu
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