Molecular regulation of thermosensitive TRP (transient receptor potential) channels
Viktorie Vlachova, Department of Cellular Neurophysiology
The sense of pain consists of the perception of distinct types of thermal, chemical, and mechanical stimuli. Recognition of these cues is executed by specialized membrane proteins expressed by polymodal sensory neurons. The ability to detect noxious stimuli is mediated by temperature-sensitive transient receptor potential (TRP) channels, collectively referred to as ‘thermo-TRPs’. These ion channels exhibit restricted specificity, such that heat stimuli activate a different class of TRP channels than cold stimuli, for example. The aim of our study is to better understand the cellular and molecular mechanisms of the processes through which thermal and algogenic (pain-producing) stimuli control gating of native and recombinant thermo-TRP channels. To address these questions, we are using high resolution patch-clamp electrophysiology in combination with a superfusion system allowing fast exchange and precise temperature control of solutions, distinct imaging techniques, molecular biology methods to engineer channels, FRET microscopy and single molecule imaging. These approaches will yield insights into the basic biology of the peripheral nervous system and may also have a potent impact on novel pain-treatment strategies.
New directions based on our past work: Regulation of TRPA1 and TRPV1 receptors
The laboratory’s main focus is TRPA1 (Biochem J 2011, 433(1): 197-204), TRPV1 and TRPV3 channels (J Biol Chem 2010, 285(53): 41455-62 ). We are interested in both the mechanistic regulation of these channels and their roles in physiological processes such as pain, temperature and mechanical sensation. Our recent results indicate that the pore structures and gating sequences of these channels involve a level of complexity not previously recognized. We use a combination of molecular biology and electrophysiology to determine receptor domains of these proteins that are involved in ion channel gating and modulation. We are continuing to identify additional functionally important domains while working towards a more comprehensive understanding of the mechanism of activation and regulation of these channels and their in vivo roles in nociception. We are particularly interested in the inter- and intra-molecular interactions in the TRPV1 transmembrane region that are just beginning to be elucidated. We have made a number of mutants in this protein domain and we are investigating the effects of these changes. We are exploring how extracellular calcium ions shape TRPA1-mediated currents and which domains are involved. One major new direction that we have decided to take is to explore the role of plasma membrane lipids in TRPV1, TRPA1 and/or TRPV3 modulation. As part of this effort we are developing FRET and single molecule imaging approaches (with engineered receptors) to image receptor activation in cells.
Requirements
Suitable candidate should have an appropriate experience in electrophysiology, cellular physiology, molecular biology and/or biochemistry, as well as working knowledge in signal transduction, more desirably ion channels and calcium signaling in primary nociceptive neurones. The successful applicant will apply state-of-the-art electrophysiological, molecular and fluorescence-based tools to investigate the activation of TRP channels. The applicant is expected to have strong desire to understand basic science, and to perform mechanistic studies. The position requires experience in electrophysiological techniques, preferably patch clamp. Experience with thermally-gated ion channels is an advantage. Experience in any of the following techniques is particularly appreciated: Ca2+ imaging, single-channel electrophysiology, molecular biology, dorsal root and/or trigeminal ganglion cell preparation, neuronal cell transfection. For more information, visit the Vlachova group’s web-site: http://www2.biomed.cas.cz/d331/eng/nocicepce_eng/nocicept_eng.html.
• PhD in biomedical/physiological sciences or related field
• Strong proficiency in electrophysiology, cellular physiology, as well as working knowledge in signal transduction, more desirably ion channels and calcium signaling in primary nociceptive neurones
• Good track record of scientific publications in international journals
• Experience of working with recombinant ion channels expressed in cell lines and with molecular biology and/or biochemistry is desirable
• Other important qualities of the appointee will be, motivation, enthusiasm, flexibility, willingness to learn, and the ability to work and interact with others in a supportive research group
• Experience with neuronal cell transfection, calcium or FRET imaging is considered a distinct advantage.
Major research duties and responsibilities for this position:
• Execution of TOP level research using multi-disciplinary approaches
• Maintenance of cell lines necessary for the experiments
• Advanced electrophysiology to study cell biological aspects of TRP channels
• Data analysis and interpretation
• Contribution towards preparation and submission of manuscripts
• Twice per year – Participate in organizing a 5-day tutoring package for undergraduate students
The Department of Cellular Neurophysiology has a long-standing tradition in physiology and build up a substantial know-how and infrastructure in the field of molecular and cellular physiology of ion channels. The department is housed in the Institute of Physiology, which integrates diverse scientific expertises in molecular and physiological science and possibility to proceed research in the new Biotechnology Institute in Prague for the advancement of innovation in translational research.