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STOWELL LAB A Biofizz Production RESEARCH PEOPLE JOBS COURSES MEETINGS LOCATION LINKS RESEARCH Our research is focused on molecular and supramolecular structures that facilitate communication between neurons at the chemical synapse and how such structures are perturbed in neurological disease. We are particularly interested in the architectural arrangement of signaling molecules and enzymes, and characterizing the ways in which such molecular assemblies are formed and undergo changes during synaptic transmission and modulation. Our approach is to investigate individual proteins using x-ray and electron crystallographic methods and to combine this information with EM images obtained via 3-D reconstruction of supramolecular assemblies and tomographic analysis of the intact chemical synapse. Our long-term goal is to construct a dynamic molecular and architectural map for the chemical synapse that will help to understand synaptic formation, transmission and plasticity. Ion channel structure and mechanism. Several ion channels are being studied with the plan of determining the molecular mechanism of their action. These include voltage gated channels responsible for propagation and termination of action potentials, calcium channels involved in signal amplification and ligand gated ion channels involved in signal detection and modulation. Using rapid affinity purification methods, along with x-ray crystallography and electron microscopy, our goal is to elucidate the structural elements of these channels in various state. Synaptic architecture, dynamics, and plasticity. Using electron tomographic methods we have begun to study the architecture of the chemical synapse in cultured neurons. Our first goal is to establish the common architectural elements present at the synapse and to identify the molecules involved using specific antibody labeling or genetic tagging. Subsequently, we will perform field potential stimulations coupled with cryogenic trapping to investigate the dynamic processes involved in synaptic transmission. Ultimately we plan to study long-term, stimulation dependent, synaptic changes in the hopes of gaining insight into the architectural elements underlying synaptic plasticity. Alzheimer's Disease. Using a variety of methods we are investigating the early stages of neurodegeneration in Alzheimer's disease. In particular we are interested in the interaction of beta-amyloid peptides with synaptophysin and the synaptophysin/synaptobrevin complex. Synaptophysin is the earliest protein degraded during Alzheimer's disease yet its role both in synaptic transmission and in Alzheimer's remains elusive. Using biochemical and biophysical methods we have discovered that beta-amyloid peptides disrupt the synaptophysin/synaptobrevin complex which results in proteolytic degredation of synaptophysin. Formation and mechanisms of supramolecular assemblies. Supramolecular organization and assembly of biomolecules occurs throughout biology. We are interested in supramolecular protein assemblies such as the channel clustering proteins rapsyn and PSD95, the self assembling GTPase dynamin, as well as the viral coat protein of tobacco mosaic virus. The interests and goals of these projects are twofold. First, to understand the role of supramolecular organization and assembly in maintaining and modulating synaptic transmission. And second, the potential of such biomolecular systems to serve as templates for nanomolecular assembly and patterning of materials. SUPPORT: CLICK TO VISIT The Beckman Foundation , The Human Frontier Science Program , The Howard Hughes Medical Institute , The Agouron Institute , National Science Foundation , National Institutes of Health , DARPA , AmideBio , Synkera , ClariMedix , AstraZeneca , Bioptix , and The University of Colorado . PUBLICATIONS: CLICK TO DOWNLOAD PDF. Adams, D.J., Nemkov, T. G., Mayer, J. P., Old, W.M., Stowell, M.H.B. (2017). Identification of the Primary Peptides Contaminant that Inhibits Fibrillation and Toxicity in Synthetic Amyloid b 42. PLoS One , 12(8). Yu, H., Rathore, S.S.,Shen, C., Liu, Y., Outang, Y., Stowell, M.H., and Shen, J. (2015). Reconstituting Intracellular Vesicle Fusion Reactions: The Essential Role of Macromolec papers/yu2015.pdf ular Crowding . J. Am. Chem. Soc. , 137 (40), pp 12873–12883. Adams, D.J., Arthur, C.P. and Stowell, M.H.B. (2015). Architecture of the Synaptophysin/Synaptobrevin Complex: Structural Evidence for an Entropic Clustering Function at the Synapse. Scientific reports 5: 13659. Basta, T., Wu H., Morphew M.K., Lee J, Ghosh, N., Lai, J, Heumann J.M., Wang K., Lee Y.C, Rees D.C., and Stowell M.H.B. (2014) Self-assembled lipid and membrane protein polyhedral nanopartic les PNAS 111 (2) 670. Wu, H.; Basta, T.; Morphew, M.; Rees, D.C.; Stowell, M.H.B.; Lee, Y.C., (2013) Microfluidic device for super-fast evaluation of membrane protein crystallization Nano/Micro Engineered and Molecular Systems (NEMS), 8th IEEE International Conference on pp.84,87, 7-10 April 2013 Arthur CP , Dean C, Pagratis M, Chapman ER & Stowell MHB (2010). Loss of synaptotagmin IV results in a reduction in synaptic vesicles and a distortion of the Golgi structure in cultured hippocampal neurons . Neuroscience 167: 135-42 Sheng JR, Grimme S, Bhattacharya P, Stowell MH, Artinger M, Prabahakar BS, Meriggioli MN (2010). In vivo adsorption of autoantibodies in myasthenia gravis using Nanodisc-incorporated acetylcholine receptor . Exp Neurol. Oct; 225(2):320-7. Arthur, C.P. and Stowell, M.H.B. (2007). S tructure of synaptophysin: A hexameric MARVEL domain channel protein, Structure, 15, 707-714. Arthur, C. P., Serrell, D. B., Pagratis, M., Potter, D. L., Finch, D. S., and Stowell, M. H. B. (2007) Electron tomographic methods for studying the chemical synapse , Cellular Electron Microscopy . 79 , 241-257. Brian A. Larsen, Michael A. Haag, Michael H. B. Stowell, David C. Walther, Albert P. Pisano, and Conrad R. Stoldt (2007). Controlling nanoparticle aggregation in colloidal microwave absorbers via interface chemistry . Proc. SPIE 6525, 652519. D. Routkevitch, O. Polyakov and M. Stowell, (2006) Micromachined Ceramic Platform for Living Neuronal Networks , Electrochem. Soc. 601 , 1265. Yeh, A.P., McMillan, A. and Stowell, M.H.B. (2006) Rapid and simple protein-stability screens: application to membrane proteins, Acta Crystallogr D Biol Crystallogr . 62:451-7. Tierney, M.L., K.E. Osborn, P.J. Milburn, Stowell, M.H.B, and S.M. Howitt. (2004). Phylogenetic conservation of disulfide-linked, dimeric acetylcholine receptor pentamers in southern ocean electric rays, J Exp Biol . 207:3581-90. Demir, M and Stowell, M.H.B. (2002) A chemoselective biomolecular template for assembling diverse nanotubular materials, Nanotechnology 13:541-544. Marks, B., M.H., Stowell , Y. Vallis , I.G. Mills, A. Gibson, C.R. Hopkins, and H.T. McMahon (2001) GTPase activity of dynamin and resulting conformational change are essential for endocytosis , Nature 410:231-235. RESEARCH PEOPLE JOBS COURSES MEETINGS LOCATION LINKS...