Bioorganic Chemistry, Medicinal Chemistry, Photochemistry

Dr. Dore's laboratory is located at NYU Abu Dhabi in the United Arab Emirates.

To increase our understanding of biology and medicine, the scientific community requires the continued development of new technologies for studying and manipulating cell physiology.  My research program in synthetic, bioorganic, biological, and medicinal chemistry aims to meet this demand by designing and synthesizing new chemistry-based technology and tools for the study of biological function.  The research is multidisciplinary in nature, involving organic chemistry, biochemistry, photochemistry, microscopy, and molecular and cell biology.  The complexity of the problems addressed necessitates collaborations with other scientists.  Currently, my research focuses on two major areas:  light-driven tools to study biological systems and the process CaaX protein maturation.  As an independent scientist, I have also conducted research to understand the action of kinesin motor protein inhibitors and the process of doctoral education.

Light-Driven Tools to Study Biological Systems

Photochemical methods in which light is used to trigger the release of a bioactive compound into a physiological environment are ideal for studying biological function and enable the conduct of experiments that would be difficult by other means.  Light-driven tools enable a high level of control of the timing, location, and amplitude of an event in a relatively non-invasive manner, especially when 2-photon excitation (2PE) is employed.  2PE enables activation of a bioactive messenger in a small volume relative to mammalian cells (1 fL, i.e., the volume of a single E. coli bacterium).  Other advantages to 2PE include less photodamage to biological tissues and the ability to conduct experiments deeper inside tissues than can be achieved using conventional 1-photon excitation (1PE).  My laboratory designs, synthesizes, studies, and develops applications for photochemically active molecules, particularly those with sensitivity to 2PE.  We are applying our photochemical technology to accurately control neural activity on the cellular scale in an intact brain to understand how information propagates in the central nervous system and to explore the role of certain genes in vertebrate development.

Caax Protein Maturation

The Ras subfamily of small GTP-binding proteins are CaaX proteins that play a prominent role in carcinogenesis; therefore, Ras proteins and Ras-regulatory proteins are considered targets for anticancer therapeutics.  The C-terminal end of the nascent protein contains a 4-residue motif where C is cysteine, a is typically an aliphatic amino acid, and X is one of several amino acids.  Three post-translational modifications are critical for the proper localization and proper function of CaaX proteins:  farnesylation by farnesyl transferase (FTase) or geranylgeranylation by geranylgeranyl transferase (GGTase); proteolysis by CaaX proteases Ras converting enzyme (Rce1p) or sterile mutant 24 (Ste24p); and carboxyl methyl esterification by isoprenylcysteine carboxyl methyltransferase (ICMT).  Ste24p and Rce1p are membrane-bound and ER localized, but have unrelated primary sequences.  Rce1 and Ste24p have distinct, but partially overlapping substrate specificities; Rce1p proteolyzes Ras, but Ste24p does not.  Ste24p is a zinc metalloprotease, but Rce1p’s mechanism of proteolysis has eluded classification.  Little structural information on Rce1p is available.  In collaboration with Walter Schmidt, we have discovered molecular scaffolds that provide the basis to design selective and potent inhibitors of Ste24p and Rce1p.  Small-molecule inhibitors of these proteases would provide insight into each enzyme’s mechanism of action and could potentially have therapeutic value.

Professor Dore is a member of the Asian Chemical Biology Initiative, http://www.asianchembio.jp/.

Publications

Ma, J.; Rea, A. C.; An, H.; Ma, C.; Guan, X.; Li, M. - D.; Su, T.; Yeung, C. S.; Harris, K. T.; Zhu, Y.; Nganga, J. L.; Fedoryak, O. D.; Dore, T. M.; Phillips, D. L. Unraveling the Mechanism of the Photodeprotection Reaction of 8-Bromo- and 8-Chloro-7-hydroxyquinoline Caged Acetates. Chem.-Eur. J. 2012, 18, 6854-6865.
Abate-Pella, D.; Zeliadt, N. A.; Dore, T. M.; Blank, D. A.; Wattenberg, E. V.; Distefano, M. D. Photochemical Modulation of Ras-Mediated Signal Transduction Using Caged Farnesyltransferase Inhibitors: Activation via One- and Two-Photon Excitation. ChemBioChem 2012, 13, 1009-1016.
Ma, J.; Cheng, S. C.; An, H.; Li, M. - D.; Ma, C.; Rea, A. C.; Zhu, Y.; Nganga, J.; Dore, T. M.; Phillips, D. L. Comparison of the Absorption, Emission, and Resonance Raman Spectra of 7-Hydroxyquinoline and 8-Bromo-7-Hydroxyquinoline Caged Acetate. J. Phys. Chem. A 2011, 115, 11632-11640. Abstract
Schmidt, W. K.; Dore, T. M. "The Ras Converting Enzyme (Rce1p): Orthologs, Enzymology, and Inhibitors." In: Tamanoi, F.; Hrycyna, C. A.; Bergo, M., eds. The Enzymes. Vol. 30B. New York: Elsevier/Academic Press; 2011:.
Dore, T. M.; Wilson, H. C. "Chromophores for the Delivery of Bioactive Molecules with Two-Photon Excitation." In: Chambers, J. J.; Kramer, R. H., eds. Photosensitive Molecules for Controlling Biological Function. New York: Humana Press; 2011:.
An, H. - Y.; Ma, C.; Li, W.; Harris, K. T.; Dore, T. M.; Phillips, D. L. Resonance Raman Characterization of the Different Forms of Ground-State 8-Substituted 7-Hydroxyquinoline Cage Acetate Compounds in Aqueous Solutions. J. Phys. Chem. A 2010, 114, 2498-2505. Abstract
Pirrung, M. C.; Dore, T. M.; Zhu, Y.; Rana, V. S. Sensitized two-photon photochemical deprotection. Chem. Commun. 2010, 46, 5313-5315. Abstract
Dechert, A. - M.; MacNamara, J. P.; Breevoort, S. R.; Hildebrandt, E. R.; Hembree, N. W.; Rea, A. C.; McLain, D. E.; Porter, S. B.; Schmidt, W. K.; Dore, T. M. Modulation of the Inhibitor Properties of (Acyloxy)methyl Ketones Toward the CaaX Proteases. Bioorg. Med. Chem. 2010, 18, 6230-6237. Abstract
An, H. - Y.; Ma, C.; Nganga, J. L.; Zhu, Y.; Dore, T. M.; Phillips, D. L. Resonance Raman Characterization of Different Forms of Ground-State 8-Bromo-7-hydroxyquinoline Caged Acetate in Aqueous Solutions. J. Phys. Chem. A 2009, 113, 2831-2837. Abstract
Davis, J. M.; Kragor, C. H.; Reddie, K. G.; Wilson, H. C.; Zhu, Y.; Dore, T. M. Substituent Effects on the Sensitivity of a Quinoline Photoremovable Protecting Group to One- and Two-Photon Excitation. J. Org. Chem. 2009, 74, 1721-1729. Abstract
Porter, S. B.; Hildebrandt, E. R.; Breevoort, S. R.; Mokry, D. Z.; Dore, T. M.; Schmidt, W. K. Inhibition of the CaaX proteases Rce1p and Ste24p by peptidyl (acyloxy)methyl ketones. Biochim. Biophys. Acta 2007, 1773, 853-862. Abstract
Reddie, K. G.; Roberts, D. R.; Dore, T. M. Inhibition of kinesin motor proteins by adociasulfate-2. J. Med. Chem. 2006, 49, 4857-4860. Abstract
Zhu, Y.; Pavlos, C. M.; Toscano, J. P.; Dore, T. M. 8-Bromo-7-hydroxyquinoline as a Photoremovable Protecting Group for Physiological Use: Mechanism and Scope. J. Am. Chem. Soc. 2006, 128, 4267-4276. Abstract
Dore, T. M. "Multiphoton Phototriggers for Exploring Cell Physiology." In: Goeldner, M.; Givens, R. S., eds. Dynamic Studies in Biology: Phototriggers, Photoswitches, and Caged Biomolecules. Weinheim, Germany: Wiley-VCH; 2005:.
Goard, M.; Aakalu, G.; Fedoryak, O. D.; Quinonez, C.; St. Julien, J.; Poteet, S. J.; Schuman, E. M.; Dore, T. M. Light-Mediated Inhibition of Protein Synthesis. Chem. Biol. 2005, 12, 685-693. Abstract
Lu, M.; Fedoryak, O. D.; Moister, B. R.; Dore, T. M. Bhc-diol as a photolabile protecting group for aldehydes and ketones. Org. Lett. 2003, 5, 2119-2122. Abstract