In this CRC project we focus on the formation and dynamics of the endocytic signaling platform and its coupling to the exocytosis domains at synapses. We will analyze whether synaptic vesicle proteins and lipids remain in part clustered after exocytosis, we will determine the required factors, and determine the mechanisms underlying the tight coupling of exocytosis and compensatory endocytosis.
Maintaining synaptic transmission requires resorting and retrieval of the fused vesicle components by compensatory endocytosis. We showed in previous studies the existence of a pre-sorted and pre-assembled readily retrievable pool (RRetP) of synaptic vesicle proteins, and identified one of them, synaptophysin 1, to be a main organizer of the RRetP by forming hetero-oligomers with the v-SNARE synaptobrevin. However, are self-assembly forces of SV components sufficient for re-clustering or do endocytic adaptor proteins and clathrin contribute? To address these questions, we utilize fluorescence live-cell imaging as well as nanoscopy and correlative electron microscopy. We also developed a novel synaptic culture system, “Xenapses”, amenable to live-cell total internal reflection microscopy. Xenapses are synapses formed by cultured mouse hippocampal neurons on micropatterned host substrates functionalized with synaptogenic proteins. Xenapses show all the hallmarks of a typical synapse, both structurally and physiologically.
- Nosov, G., Kahms, M., Klingauf, J. (2020) The Decade of Super-Resolution Microscopy of the Presynapse. Front. Synaptic Neurosci. 12, 32.
- Goossen-Schmidt, N.C., Schnieder, M., Hüve, J., Klingauf, J. (2020). Switching behaviour of dSTORM dyes in glycerol-containing buffer. Sci Rep. 10(1),13746.
- Viplav, A., Saha, T., Huertas, J., Selenschik, P., Ebrahimkutty, M.P., Grill, D., Lehrich, J., Hentschel, A., Biasizzo, M., Mengoni, S., Ahrends, R., Gerke, V., Cojocaru, V., Klingauf, J., Galic, M. (2019). ArhGEF37 assists dynamin 2 during clathrin-mediated endocytosis. J Cell Sci. 132(9)
- Schmidt, N.C., Kahms, M., Hüve, J., Klingauf, J. (2018). Intrinsic refractive index matched 3D dSTORM with two objectives: Comparison of detection techniques. Sci Rep. 8(1),13343.
- Kahms, M., Klingauf, J. (2018) Novel pH-Sensitive Lipid Based Exo-Endocytosis Tracers Reveal Fast Intermixing of Synaptic Vesicle Pools. Front Cell Neurosci. 12, 18.
- Martineau, M., Guzman, R.E., Fahlke, C., Klingauf, J. (2017). VGLUT1 functions as a glutamate/proton exchanger with a chloride channel activity at hippocampal glutamatergic terminals. Nat. Commun. 8, 2279.
- Bodzęta, A., Kahms, M., Klingauf, J. (2017). The Presynaptic v-ATPase Reversibly Disassembles and Thereby Modulates Exocytosis but Is Not Part of the Fusion Machinery. Cell Rep. 20(6),1348-59.
- Boening, D., Gauthier-Kemper, A., Gmeiner, B., Klingauf, J. (2017). Cluster Recognition by Delaunay Triangulation of Synaptic Proteins in 3D. Adv Biosyst. 1(10), e1700091.
- Rajappa, R., Gauthier-Kemper, A., Böning, D., Hüve, J., Klingauf J. (2016). Synaptophysin 1 clears Synaptobrevin 2 from the presynaptic active zone to prevent short-term depression. Cell Rep. 14, 1369-81.