Presynaptic modulation: roles of G Proteins and ion channels
Keywords
Ligand-gated ion channels, G protein-coupled receptors, nucleotide receptors; voltage-activated Ca2+ channels, Kv7 channels;
Research interest of the Faculty Member
Dr. Boehm is interested in the molecular mechanisms and functional consequences of the modulation of transmitter release via presynaptic receptors. He has pursued this research topic by investigating central and peripheral neurons. In the recent past, the focus of research was the identification of autoregulatory nucleotide receptors that mediate the feedback control of transmitter release from sympathetic neurons. In hippocampal neurons, Dr. Boehm investigated inhibitory presynaptic auto- and heteroreceptors and is now interested in presynaptic transmitter-gated as well as voltage-gated ion channels. In addition to presynaptic mechanisms, the molecular pharmacology of neuronal ion channels and P2Y receptors is a research interest of Dr. Boehm.
Collaborating research groups where PhD Students could perform their research stay abroad
Dr. Vincent O’Connor, Centre for Biosciences, University of Southampton, Building 85, University Road, Southampton, SO17 1BJ, UK
Dr. Mark S. Shapiro, Department of Physiology, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
Dr. Hanns Ulrich Zeilhofer, Institute of Pharmacology and Toxicology, University of Zurich, CH-8057 Zurich, Switzerland
Know-how and infrastructure of the research group
This research group was the first to describe facilitatory presynaptic P2X receptors (Boehm, 1999) and to identify inhibitory and facilitatory presynaptic P2Y receptors (Lechner et al, 2004; Chandaka et al, 2011), both mediating autoregulation of transmitter release from sympathetic neurons. They characterized the role of Ca2+/calmodulin in the autoregulation of glutamate release from hippocampal neurons (O’Connor et al, 1999) and delineated the control of neuronal Ca2+ channels via phosphatidylinositol bisphosphates as a signalling mechanism underlying presynaptic inhibition (Lechner et al, 2005; Kubista et al, 2008).
The group uses primary cultures of mouse and rat hippocampal, spinal cord, sensory, and sympathetic neurons (Boehm and Betz, 1997; Boehm 1999) for transfection (Goetze et al, 2005), for the recording of autaptic and miniature synaptic currents (Boehm and Betz, 1997), of currents through Ca2+ and Kv7 channels (Lechner et al, 2003 and 2005), and for the determination of transmitter release via radiotracers (Boehm, 1999). Intracellular second messengers (cAMP and inositol phosphates) are quantified by radioactive labelling and subsequent separation by column chromatography (Moskvina et al, 2003). FRET of fusion proteins containing CFP and YFP is done via fluorescent microscopy (Schicker et al, 2008).
Members of this research group have access to two complete cell culture labs (preparative microscope, sterile hoods, two incubators, fluorescence microscopes), one standard radioactivity lab, one standard biochemistry and molecular biology lab, a fluorescence microscope with monochromator, filter wheels, and CCD camera, one confocal laser scanning microscope, and 5 complete patch clamp rigs.