We examine the nature of interactions between ion channels at the molecular and physiological levels, with an emphasis on channels activated primarily in the subthreshold region that underlie spike discharge. Recent work has focused on the relationship between a low voltage-activated T-type calcium channel and Kv4, HCN, BK, and IKCa channels, and their role in controlling the response to synaptic input or the pattern of spike output in cerebellar and hippocampal neurons. We use a combination of electrophysiology, molecular biology, immunocytochemistry, and optogenetics. With our finding that IKCa channels are expressed in the CNS, the functional role of this channel type is also being investigated in hippocampal and other central neurons. Contact us to talk about projects available for students to undertake and build on by applying the principles of scientific investigation.
- Alberta Innovates-Health Solutions - Scientist
- Great Supervisor Award, Faculty of Graduate Students
- Department Neuroscience - Outstanding Graduate Training Contribution
- Dean’s Publication and Mentorship Prize
- Associate Dean (Research Grants), Cumming School of Medicine
- You Make a Difference award, VPR office, University of Calgary
CIHR Operating Grant 2012 - 2017
Principal Investigator. Co-applicants: G.W. Zamponi
Title: Interactions between Cav3 and Kv4 ion channels
CIHR Operating Grant 2014 - 2019
Principal Investigator. Collaborators: G.W. Zamponi, P. Stys, C. Teskey
Title: Novel roles for KCa3.1 channels in the CNS
NSERC Discovery Grant 2016 - 2021
Title: Facilitation of L-type calcium channels
Our lab studies Cav3 calcium channel distribution, function, and interactions with potassium channels, publishing 27 manuscripts and invited reviews on these topics over the past 10 years. Several studies are in high profile journals (PNAS, Nat. Neurosci, Cell Reports, J Neurosci) with 4 citations in the Faculty of 1000 (see http://people.ucalgary.ca/~rwturner/). Our lab has 5 recording setups specialized for single channel recordings, optogenetics, voltage-clamp, and dynamic clamp, with a microscope room and shared culture facilities. Our lab is just down the hall from our collaborators, allowing for daily exchange between trainees and access to each other’s expertise and infrastructure. We further access core facilities to use spectral confocal microscopes to image FRET, a Microscopy and Imaging Facility for electron microscopy, a University Core DNA services for gene expression analyses, and a Center for Genome Engineering to contruct transgenic animals. A full time technician and Research Associate assists trainees with histology, immunocytochemistry, cell cultures, and protein biochemical and molecular assays.
The Hotchkiss Brain Institute (HBI), Cumming School of Medicine (CSM) and university provide resources and training programs, with 100 students in the Dept. Neuroscience and ~200 PDFs in the CSM coordinated by a PDF office. Trainees benefit from a weekly HBI seminar series and a Professional Development program. Applications for competitive salary support can be made through the HBI, the AIHS, and new CSM programs to recruit >100 PDFs and 50 students within 5 years to further establish Calgary as a national center for outstanding training. Trainees in our lab present and publish their work, with 15 trainees attending 10 international meetings to present 32 posters in the past 5 years, and typically publish 2-10 manuscripts arising from their work. As a result trainees gain the ability to attract top awards, including University Killam, CIHR-CGS Studentships, CIHR and AI-HS PDFs, HBI PhD Student of the Year (2), and a PhD Governor General Gold Medal award. Altogether we have an outstanding research and training program with access to all the infrastructure, technology, and support personnel necessary for trainees to achieve success in their future career choices.
Control over the excitability of neurons in the brain depends on the activity of membrane channels that conduct calcium or potassium ions to control the membrane voltage and modify synaptic responses and action potential (spike) firing. We study the distribution and function of a low voltage-activated class of T type (Cav3) calcium channels that exhibit unique properties of activation and inactivation (closing) to provide an excitatory stimulus to neurons. We also examine the role of voltage- or calcium-gated potassium channels that act to reduce excitability. The combination of this work has revealed several previously unrecognized ion channel signaling complexes comprised of Cav3 channels and any of Kv4, BK, or IKCa channels. Together these complexes provide unique responses such as external calcium sensors or extremely long slow afterhyperpolarizations (sAHP) to regulate cell excitability in both cerebellum and hippocampus. Understanding these interactions and where they exert control over neuronal excitability is the first step in potentially identifying therapeutic agents important for treating dysfunctional output in disease states.
The following is a selection of key work we have published in recent years and why they are important. For the most recent publications please visit: