B.S. Chemistry (1997) The College of New Jersey Ph.D. Chemistry (2002) University of California Beckman Senior Research Fellow (2002-2005) California Institute of Technology

Our laboratory strives to understand the cooperative dynamics of proteins when they operate as highly organized and integrated assemblies. We adopt engineering approaches that enable model systems of natural multiprotein assemblies to be reconstructed in vitro while preserving the intricate molecular features of these assemblies. Our techniques allow the molecular orchestration of interacting proteins to be sensitively probed, while defining specific molecular interactions that are normally confounded by the diversity of cellular environments. In this way, we are able to bridge the gaps between our understanding of the stochastic dynamics of isolated single molecules and the operation of multiprotein assemblies in physiological settings. This research naturally involves a combination of state-of-the-art synthetic techniques to construct multiprotein architectures, and the development of instrumentation to investigate collective protein dynamics with single-molecule precision. While our methods can be generalized, enabling investigation of a variety of multiprotein networks and assemblies, so far this research concentrates on two areas: IN VITRO MODELING OF INTRACELLULAR TRAFFICKING AND TRANSPORT: The transport of intracellular cargo to different locations of the cell involves the activated mechanics of biomotor proteins. In many cases, these proteins interact with one another, as well as their associated regulatory proteins, in order to control and optimize transport. We seek to understand mechanistic pictures of these processes by reconstructing these assemblies in vitro and investigating their cooperative dynamics using single-molecule microscopy and spectroscopy techniques. Assemblies are constructed using engineered molecular scaffolds, the properties of which are defined by artificial proteins and DNA nanostructures. These scaffolds provide a means to accurately specify the supramolecular architecture of assemblies by defining the number and types of coupled motors, intermotor distances, and the elasticity of motor interconnects. These capabilities will enable us to develop detailed structure-activity relationships that will unveil the fundamental scaling laws that govern collective biomotor transport. Furthermore, we can probe the molecular orchestration that occurs within these assemblies with single-molecule sensitivity, bringing new insight to our understanding of the rich dynamics observed during motor driven intracellular transport. ENCODING THE SELF-ORGANIZED MECHANICS OF INTERNALLY DRIVEN FILAMENTS: The ability to generate coherent and sustained oscillations in highly viscous and damped cellular environments is of fundamental importance in biology. This type of mechanics provides cells with a means for self-propulsion and to stir their surrounding fluids using the controlled beating of internally driven filaments. Similar mechanical behavior is harnessed by cells to detect and amplify extremely small signals, which in some cases, are no larger than thermal noise. Motions of these filaments are self-generated by large collections of biomotor proteins that are arranged into complex architectures, such as those seen in axonemal cilia and flagella. With these systems as inspiration, we are engineering model biomotor assemblies that operate as shearing-mode oscillators, and emulate the dynamics of axonemal assemblies. Using artificial proteins to define and tune the properties of biomotors and nanomechanical devices to probe the motions of these motors, we are developing strategies to encode the cooperative dynamics of internally driven filaments. These efforts will impact our fundamental knowledge of collective biomotor mechanics, and provide guidelines to harness the mechanochemical mechanisms cells employ to sense, respond, and adapt to their surroundings.

K. Uppulary, J.W. Driver, M.R. Diehl, A.B. Kolomeisky "Analysis of cooperative responses of multiple kinesin motors to structural and chemical factors" Journal of Cellular and Molecular Bioengineering 6, 38-47 (2013). E. Kumar, D.S. Tsao, A. Radhakrishnan, M.R. Diehl Building cells for quantitative, live-cell analyses of collective motor protein functions. Methods in Enzymology D.Y. Duose, R.M. Schweller, J. Zamak, A. Rogers, W.N. Hittelman, M.R. Diehl "Configuring robust DNA strand displacement reactions for in situ molecular analyses" Nucleic Acids Research, 40, 3289-3298 (2012). D.Y. Duose, R.M. Schweller, J. Zamak, A. Rogers, W.N. Hittelman, M.R. Diehl "Configuring robust DNA strand displacement reactions for in situ molecular analyses" Nucleic Acids Research 40, 3289-3298 (2012) A. Rogers, P.E. Constantinou, D.K. Jamison, J.W. Driver, M.R. Diehl Construction and analysis of elastically coupled multiple-motor systems. Methods in Enzymology, 520 H. Lu, A.K. Yefremov, C.D. Bookwalter, E.B. Kremestsova, J.W. Driver, K. Trybus, M.R. Diehl "Cooperative dynamics of elastically-coupled myosinV motors" Journal of Biological Chemistry 287, 27253-27761 (2012) D.K Jamison, J. Driver, M.R. Diehl "Cooperative responses of multiple kinesins to variable and constant loads" Journal of Biological Chemistry 287, 3357-3365 (2012) D.K Jamison, J. Driver, M.R. Diehl "Cooperative responses of multiple kinesins to variable and constant loads" – Journal of Biological Chemistry 287, 3357-3365 (2012). D.W. Driver, A.R. Rogers, D.K. Jamison, R.K. Das., A.B. Kolomeisky, M.R. Diehl "Coupling between Motor Proteins Determines Dynamic Behaviors of Motor Protein Assemblies" Physical Chemistry Chemical Physics 12, 10398 (2010) A.K. Efremov, A. Radhakrishan, D.S. Tsao, C.S. Bookwalter, K.M. Trybus, M.R. Diehl Delineating cooperative responses of processive motors in living cells. Proceedings of the National Academy of Sciences, USA 111: E334-E4343 A.K. Efremov, A. Radhakrishan, D. Tsao, C.S. Bookwalter, K.M. Trybus, M.R. Diehl "Delineating cooperative responses of processive motors in living cells" accepted to PNAS (2013) K. Uppulary, A.K. Efremov, J.W. Driver, D.K. Jamison, M.R. Diehl, A.B. Kolomeisky "How the interplay between mechanical strain and non-mechanical interactions affect multiple kinesin dynamics" Journal of Physical Chemistry B 116, 8846-8855 (2012) K.I. McConnell, R.M. Schweller, M.R. Diehl, J. Suh. "Live-cell microarray surface coatings supporting reverse transduction by adeno-associated viruses" BioTechniques 51, 255-258 (2011) D.S. Tsao, M.R. Diehl Molecular motors: myosins move ahead of the pack. , 9: 9-10 D.S. Tsao, M.R. Diehl. "Molecular motors: myosins move ahead of the pack" Nature Nanotechnology 9, 9-10 (2014). Eric Kumar, David Tsao, M. R. Diehl Motor mutants bring wild-type motors to a halt stochastically. Biophysical Journal , 107: 279-281 D.Y. Duose, R.M. Schweller, W.N. Hittelman, M.R. Diehl "Multiplexed and Reiterative Fluorescent Labeling via DNA Circuitry" Bioconjugate Chemistry 21, 2327-2331 (2010). R.S. Schweller, J. Zimak, D.Y. Duose, W.N. Hittelman, M.R. Diehl. "Multiplexed in situ immunofluorescence via dynamic DNA complexes" Angewandte Chemie 51, 9292-9296 (2012) A. R. Rogers, J. Driver, P.E. Constantinou, M.R. Diehl "Negative Interference Dominates Collective Transport of Kinesin Motors in the Absence of Load" PCCP 11, 4882 (2009) J.W. Driver, D.K. Jamison, A.R. Rogers, K. Uppulury, A.B. Kolomeisky, M.R. Diehl "Productive cooperation among processive motors depends on their mechanochemical efficiencies" Biophysical Journal 101, 386 (2011) J. Zimak, R.S. Schweller, W.N. Hittelman, M.R. Diehl "Programming in situ immunofluorescence intensities through interchangeable reactions of dynamic DNA complexes" ChemBioChem, Dec 21;13(18):2722-8. D.K. Jamison, J.D. Driver, M.R. Diehl "Structure-function analyses of single, multiple motor complexes" invited and in preparation for special issue in Methods in Enzymology (October 2013). D.K. Jamison, J.W. Driver, A.R. Rogers, P.E. Constantinou, M.R. Diehl "Two Kinesins Transport Cargo Primarily via the Action of One: Implications for Intracellular Transport," Biophysical Journal 99, 2967-2977 (2010). K. Uppulary, J.W. Driver, M.R. Diehl, A.B. Kolomeisky "Analysis of cooperative responses of multiple kinesin motors to structural and chemical factors" Journal of Cellular and Molecular Bioengineering: Special issue on biomolecular motors and motor assemblies, 6, 38-47 (2013). M.R. Diehl "Templating a molecular tug-of-war" Science 338, 626-623 (2012) M.R. Diehl*, K. Zhang, H.J. Lee, D.A. Tirrell Engineering Cooperativity in Biomotor-Protein Assemblies. Science, 311 2006: 1468 K. Zhang, M.R. Diehl, D.A. Tirrell Artificial Polypeptide Scaffold for Protein Immobilization. J. Am. Chem. Soc., 127 2005: 10136 M.R. Diehl, D.W. Steuerman, H-R. Tseng, S.A. Vignon, A. Star, P.C. Celestre, J.F. Stoddart, J.R. Heath Single-Walled Carbon Nanotube-Based Molecular Switch Tunnel Junctions. Chem. Phys. Chem., 4 2003: 1335 M.R. Diehl, S. Yaliraki, R. Beckman, M. Barahona, J.R. Heath Self-Assembled, Deterministic Carbon Nanotube Wiring Networks. Angew. Chem. Int. Ed., 41 2002: 353