We study glia-synapse interaction, with a focus on its structural correlate, the perisynaptic astrocyte process. These astrocytic processes are often extremely deli¬cate (<100 nm) and can withdraw from or approach synapses in an activity-dependent manner. We investigate mechanisms underlying their formation and structural plasticity. In the animal, this is studied in the context of hippocampal plasticity, circadian rhythms (suprachiasmatic nucleus), and neuroendocrine regulation (median eminence, pituitary). Since astrocytes may also release ‘gliotransmitters’ in the synaptic micro-environment, we study astrocytic organelles and organelle systems contributing to vesicular release. Importantly, our results derived from cell culture or rodent brain are transferred to the human brain for possible medical relevance.
· high resolution light microscopy, deconvolution, 3D reconstructions for visualization of single intracellular organelles, and glial morphology, mostly by immunofluorescence
· primary cultures of astrocytes to investigate protein localization (immunofluorescence) and protein function (transfection with contructs containing GFP / siRNA)
· live microscopy for filopodia dynamics and protein redistribution (transfection),
· immuno-electron microscopy to investigate protein distribution in the submicroscopic glial processes in the brain,
Langer J, Gerkau NJ, Derouiche A, Kleinhans C, Moshrefi-Ravasdjani B, Fredrich
M, Kafitz KW, Seifert G, Steinhäuser C, Rose CR.
Rapid sodium signaling couples glutamate uptake to breakdown of ATP in perivascular astrocyte endfeet.
Glia 65:293-308 (2017) | DOI: 10.1002/glia.23092
Derouiche A, Haseleu J, Korf HW
Fine Astrocyte Processes Contain Very Small Mitochondria: Glial Oxidative Capability May Fuel Transmitter Metabolism.
Neurochem Res (2015) 40:2402-2413 | doi.org/10.1007/s11064-015-1563-8
Anlauf E, Derouiche A
Glutamine Synthetase as an Astrocytic Marker: Its Cell Type and Vesicle Localization.
Front Endocrinol (2013) 4:144 | doi: 10.3389/fendo.2013.00144
J. Haseleu, E. Anlauf, S. Blaess, E. Endl, A. Derouiche
Studying subcellular detail in fixed astrocytes: dissociation of morphologically intact glial cells (DIMIGs)
Front Cell Neurosci 7:54 (2013) | doi: 10.3389/fncel.2013.00054
M. Lavialle, G. Aumann, E. Anlauf, F. Pröls, M. Arpin, und A. Derouiche
Structural plasticity of perisynaptic astrocyte processes involves ezrin and metabotropic glutamate receptors.
Proc Natl Acad Sci USA 108:12915-12919 (2011) | doi: 10.1073/pnas.1100957108