Fields of Interest

Structural biochemistry/neurobiology; ultrastructural neuropathology of and adhesive mechanisms in CNS and PNS myelins; fibrillogenesis and molecular organization of amyloid assemblies; remyelination; spinal cord injury; Alzheimer's disease; prion diseases.

Academic Profile

Our current research interests are focused in two areas: the structure and dynamic membrane interactions in abnormal nerve myelin, in which alterations have resulted from experimental, pathological, or genetic conditions; and the molecular organization of amyloid, which are deposits of mis-folded polypeptides involved in certain neurodegenerative diseases (including Alzheimer's disease, Huntington's disease and prion diseases) and in systematic amyloidoses. To link structure and composition at the molecular, macromolecular and tissue levels in the nervous system, our studies in these two areas utilize x-ray diffraction, microscopy at the light and ultrastructural levels, a variety of protein and lipid biochemical techniques, and molecular modeling.

What holds myelin together, and how are its constituents targeted in diseases? To characterize the molecular organization of lipids and proteins in nerve myelin membranes, and to define the molecular interactions of its membrane arrays, we are correlating biophysical and biochemical results from different types of specimens (e.g., whole unfixed or fixed tissue from a phylogenetic range of vertebrates, tissue homogenates, tissue fractions and model lipid/protein systems). Among the questions we are addressing: how does the organization of proteins and lipids in myelin account for the inter-membrane interactions of the membranes? What is the structural basis of demyelination? Our findings are relevant to understanding the process of membrane disruption and delamination which occurs in demyelinating diseases such as multiple sclerosis and certain peripheral neuropathies. Our current focus is on understanding how specific mutations in myelin adhesion proteins or in lipid biosynthetic pathways affect the stability and functionality of the myelin.

What is the process by which proteins or their fragments self-assemble to form potentially cytotoxic amyloid deposits? The molecular organization of paired helical filaments, amyloid plaque cores and cerebrovascular amyloid isolated from Alzheimer's disease (AD) brain are being studied using a variety of structural techniques. High-resolution x-ray fiber patterns and electron microscopic images are being obtained from in vitro assemblies of synthetic polypeptides homologous with AD amyloid. Determining the dimensions and spatial organization of the structural units that comprise paired helical filaments, AD amyloids and related in vitro assemblies from prion diseases and from other amyloidoses will illuminate our understanding of their formation, interrelationships and stability, and will provide insight on how they might be related to or derive from normally occurring cellular components. These findings are also relevant to the general problem of protein folding. Current efforts are directed at developing a novel screen for assessing whether or not specific compounds can inhibit amyloid formation, and if so, by what mechanism.

 

 

Representative Publications

Avila RA, Inouye H, Feltri ML, Wrabetz L, Kirschner DA (2010) P0 (protein zero) mutation Ser34Cys underlies instability of internodal myelin in S63C mice. J Biol Chem, Oct 11. [Epub ahead of print].

Inouye, H., Gleason, K.A., Decatur, S.M., Kirschner, D.A. 2010. Differential effects of Phe19 and Phe20 on fibril formation by amyloidogenic peptide Aβ16-22 (Ac-KLVFFAE-NH₂). Proteins: Structure, Function, and Bioinformatics 78: 2306–2321 (link to PubMed abstract).

Kirschner, D.A., Avila, R.L., Luoma, A., Enzmann, G.U., Agrawal, D., Inouye, H., Bunge, M.B., Kocsis, J.D., Peters, A., Whittemore, S. 2010. Rapid assessment of internodal myelin integrity in CNS tissue. Journal of Neuroscience Research 88: 712–723 (link to PubMed abstract).

Verheijen, M.H., Camargo, N., Nadra, K., de Preux, A.-S., Verdier, V., Luoma, A.M., Crowther, M., Inouye, H., Shimano, H., Chen, S., Brouwers, J., Helms, B.J., Feltri, M.L., Wrabetz, L., Kirschner, D.A., Chrast, R., Smit, A.B. 2009. SREBP cleavage activation protein (SCAP) is required for dynamic synthesis of a proper Schwann cell myelin membrane. Proceedings of the National Academy of Sciences of the United States of America 106: 21383–8 (link to PubMed abstract).

Agrawal, D., Hawk, R., Avila, R.L., Inouye, H., Kirschner, D.A. 2009. Internodal myelination during development quantitated using x-ray diffraction. Journal of Structural Biology 168: 521–526 (link to PubMed abstract).

Kirschner, D.A., Karthigesan, J., Bizzozero, O.A., Kosaras, B., Inouye, H. 2009. Myelin structure and composition of myelinated tissue in the African lungfish. Neuron Glia Biology 4: 59–70 (link to PubMed abstract).

Inouye, H., and Kirschner, D.A. 2008. Myelin: A one-dimensional biological “crystal” for x-ray and neutron scattering. In: Molecules: Aggregation, Nucleation, Crystallization — Beyond Medical and Other Implications (Eds. J. Sedzik, P. Riccio), World Scientific Publishing, Singapore.

Flores, A.I., Narayanan, S.P., Morse, E., Shick, H.B., Avila, R.L., Kirschner, D.A., and Macklin, W.B. 2008. Constitutively active Akt induces myelination in the central nervous system. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience 28: 7174–83 (link to PubMed abstract).

Kirschner, D.A., Gross, A.A., Hidalgo, M., Inouye, H., Gleason, K., Abdelsayed, G., Castillo, G.M., Snow, A.D., Pozo-Ramajo, A., Petty, S.A., and Decatur, S.M. 2008. Fiber diffraction as a screen for amyloid inhibitors. Current Alzheimer Research 5: 288–307 (link to PubMed abstract).

Luo, X.Y., Cerullo, J., Dawli, T., Priest, C., Haddadin, Z., Kim, A., Inouye, H., Suffoletto, B.P., Avila, R.L., Lees, J.P., Sharma, D., Xie, B., Costello, C.E., and Kirschner, D.A. 2008. Peripheral myelin of Xenopus laevis: role of electrostatic and hydrophobic interactions in membrane compaction. Journal of Structural Biology 162: 170–183 (link to PubMed abstract).

Luo, X., Inouye, H., Sharma, D., Lee, D., Avila, R.L., Salmona, M., and Kirschner, D.A. 2007. Cytoplasmic domain of zebrafish myelin P0: adhesive role depends on beta-conformation. Biophysical Journal 93: 3515–3528 (link to PubMed abstract).

Luo, X.Y., Sharma, D., Inouye, H., Lee, D., Avila, R.L., Salmona, M., and Kirschner, D.A. 2007. Cytoplasmic domain of human myelin P0 likely folded as beta-structure in compact myelin. Biophysical Journal 92: 1585–1597 (link to PubMed abstract).

Avila, R.A., Tevlin, B.R., Lees, J.P., Inouye, H., and Kirschner, D.A. 2007. Myelin structure and composition in zebrafish. Neurochemical Research 32: 197–209 (link to PubMed abstract).

Yin, X., Baek, R.C., Kirschner, D.A., Peterson, A., Fujii, Y., Nave, K.A., Macklin, W.B., and Trapp, B.D. 2006. Evolution of a neuroprotective function of central nervous system myelin. Journal of Cell Biology 172: 469–478 (link to PubMed abstract).

Wrabetz, L., D’Antonio, M., Pennuto, M., Dati, G., Tinelli, E., Fratta, P., Previtali, S., Imperiale, D., Zielasek, J., Toyka, K., Avila, R.A., Kirschner, D.A., Messing, A., Feltri, M.L., and Quattrini, A. 2006. Different intracellular pathomechanisms produce diverse MPZ-neuropathies in transgenic mice. Journal of Neuroscience 26: 2358–2368 (link to PubMed abstract).

Inouye, H., Sharma, D., Goux, W.J., and Kirschner, D.A. 2006. Structure of core domain of fibril-forming PHF/tau fragments. Biophysical Journal 90: 1774–1789 (link to PubMed abstract).

Shinchuk, L. M., Sharma, D., Blondelle, S.Y., Reixach, N., Inouye, H., and Kirschner, D.A. 2005. Poly(L-alanine) expansions form core beta-sheets that nucleate amyloid assembly. Proteins: Structure, Function, and Bioinformatics 61: 579–589 (link to PubMed abstract).

Sharma, D., Shinchuk, L.M., Inouye, H., Wetzel, R., and Kirschner, D.A. 2005. PolyGlutamine homopolymers having 8-45 residues form slab-like beta-crystallite assemblies. Proteins: Structure, Function, and Bioinformatics 61: 398–411 (link to PubMed abstract).

Avila, R.A., Inouye, H., Baek, R., Yin, X., Trapp, B.D., Feltri, M.L., Wrabetz, L., and Kirschner, D.A. 2005. Structure and stability of internodal myelin in mouse models of hereditary neuropathy. Journal of Neuropathology & Experimental Neurology 64: 976–990 (link to PubMed abstract).

Kirschner, D.A., Wrabetz, L., and Feltri, M.L. 2004. The P0 Gene. In: Myelin Biology and Disorders 1, (Ed. R.A. Lazzarini et al.), Elsevier/Academic Press, NY, pp. 523–545.

Inouye, H., Bond, J.E., Deverin, S.P., Lim, A., Costello, C.E., and Kirschner, D.A. 2002. Molecular organization of amyloid protofilament-like assembly of betabellin 15D: Helical array of beta-sandwiches. Biophysical Journal 83: 1716–1727 (link to PubMed abstract).

Thompson, A.J., Cronin, M.S., and Kirschner, D.A. 2002. Myelin protein zero (P0) exists as dimers and tetramers in native membranes of Xenopus laevis peripheral nerve. Journal of Neuroscience Research 67(6): 766–771 (link to PubMed abstract).

Inouye, H., Kirschner, D.A. 2000. A-beta fibrillogenesis: Kinetic parameters for fiber formation from Congo red binding. Journal of Structural Biology 130: 123–129 (link to PubMed abstract).

Inouye, H., Bond, J., Baldwin, M.A., Ball, H.L., Prusiner, S.B., and Kirschner, D.A. 2000. Structural changes in a hydrophobic domain of the prion protein induced by hydration and by Ala→Val and Pro→Leu substitutions. Journal of Molecular Biology 300: 1285–1298 (link to PubMed abstract).

Riccio, P., Fasano, A., Borenshtein, N., Bleve-Zacheo, T., and Kirschner, D.A. 2000. Multilamellar packing of myelin modeled by lipid-bound MBP. Journal of Neuroscience Research 59: 513–521 (link to PubMed abstract).

Inouye, H., Tsuruta, H., Sedzik, Uyemura, and Kirschner, D.A. 1999.  Tetrameric assembly of full sequence P0 myelin glycoprotein by synchrotron x-ray scattering. Biophysical Journal 76: 423–437 (link to PubMed abstract).

Malinchik, S.B., Inouye, H., Szumowski, K.E., and Kirschner, D.A. 1998. Structural analysis of Alzheimer's beta(1-40) amyloid: Protofilament assembly of tubular fibrils. Biophysical Journal 74: 537–545 (link to PubMed abstract).

Kirschner, D.A., Elliott-Bryant, R., Szumowski, K.E., Gonnerman, W.A., Kindy, M.S., Sipe, J., and Cathcart, E.S. 1998. In vitro amyloid fibril formation by synthetic peptides corresponding to the amino terminus of apoSAA isoforms from amyloid-susceptible and amyloid-resistant mice. Journal of Structural Biology 124: 88–98 (link to PubMed abstract).

Kirschner, D.A., Inouye, H., and Saavedra, R.A. 1996. Membrane adhesion in peripheral myelin: Good and bad wraps with protein P0. Structure 4: 1239–1244 (link to PubMed abstract).

Inouye, H., Fraser, P.E., and Kirschner, D.A. 1993. Structure of beta-crystallite assemblies formed by Alzheimer beta-amyloid protein analogues: analysis by x-ray diffraction. Biophysical Journal 64: 502–519 (link to PubMed abstract).