Kerry R. Delaney & the lab at Univ. of Victoria

Neurophysiological Research:

  • Mechanisms of Synaptic Transmission and Plasticity
  • Olfactory Bulb: Cellular and Network Analysis

    • Funded positions available as of Jan. 2010:

  • Postdoctoral Fellow Cellular neurophysiology
  • Graduate student (MSc or PhD) Cellular neurophysiology

    1992 = before, 2008 = after...

    You decide: Is science good for you?

    Professor
    Dept. of Biology
    Box 3020 Stn CSC
    University of Victoria
    Victoria, British Columbia
    Canada V8W 3N5
    Voice-lab: (250) 472-5656
    Voice-office: (250) 472-5657
    FAX: (250) 721-7021
    kdelaney@uvic.ca

  • UVic Biology Dept.
  • UVIC Cellular Neuroscience Group
  • ICORD Spinal cord research institute
  • Brain Research Centre

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    Mitral cell apical dendrites filled with Oregon green BAPTA-1 dextran in an intact frog brain. This image is a maximum intensity projection of fifty optical sections obtained between 45 and 70 microns below the surface using 2-photon microscopy. FOV 90 microns wide.

  • So you want to be a grad student....
  • Biographical Sketch
  • Publication List (some PDF files)
  • IMAGES related to our research
  • Equipment Wanted to buy
  • Photos of lab hiking trips etc.

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    Olfactory bulb confocal maximum intensity projection image. 45 microns of depth of olfactory bulb is shown, coded from red to purple. Neurons filled by local injection of dextran conjugated Alexa-488. Central neuron is a granule cell. Spiny dendrites from out of frame granule cells as wells as smooth mitral cell dendrites and axons can also be seen.

    Current trainees:
  • Leslie Rietveld (MSc student)
  • Ian Swan (MSc student)

    • Current PDFs:
  • Dr. Adam Fekete

    • List of Former trainees

    Research

    Our laboratory is primarily interested in synaptic physiology which results in a wide diversity of projects and opportunities for trainees with a variety of interests and experience. For all our work we combine a variety of electrophysiological and optical techniques. These include whole cell patch clamp, sharp microelectrode and field potential recordings combined with widefield CCD and 2-photon laser scanning imaging and photomultiplier based spot measurements, mostly using Ca2+ indicator dyes. Thanks to generous support from the Michael Smith Foundation for Health Research and ICORD we have a pair of two 2-photon microscopes suitable for in vivo imaging and electrophysiology in small animals (rats, mice and frogs) and for mammalian brain slice and isolated frog/turtle brains. Other than the lasers, these apparatus were built from scratch using old car parts and stuff I "found" in the garbage cans at Bell labs a decade ago. A bit of an exaggeration but they are definitely "home-made". A flexible 2-photon imaging program that coordinates acquisition of optical and electrophysiological signals was written entirely by Dr. James Boyd working our lab using Igor (Wavemetrics) and C++. (Jamie is currently employed with Tim Murphy's group at UBC.) and has many anatomical and quantitative analysis features. Two microscopes configured for slice or whole animal electrophysiology beam-share a single Coherent Verdi-10/Mira 900 laser system. Many thanks are due to David Kleinfeld at UCSD for some key electronics circuits and technical help along the way, and of course Herr Dr. Winfried Denk who taught me not to bring my head down to tabletop level when the laser is on by cuffing me severely about the ears.

    We are fortunate to have strong collaborative ties to researchers at the University of British Columbia. Tim Murphy (UBC, Psychiatry) and I have been working together closely for several years through a combined interest in synaptic physiology and functional imaging using 2-photon microscopy. At the University of Victoria recent growth in the area of cellular and systems neuroscience has resulted in formation of Cellular Neuroscience Group with an active collaborative mix of new and established research laboratories. A degree-granting, Graduate Program in Neuroscience is anticipated to be on-line in Sept. 2010 comprised of faculty and trainees from the Depts. of Biology, Psychology, Biochemistry and Microbiology, Physical Education and the Division of Medical Sciences.

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    Our laboratory is also a member of ICORD, The International Collaboration on Repair Discoveries (brain and spinal cord repair) funded by the Rick Hansen Neurotrauma Initiative, based in Vancouver. We are active members of UVic's CanAssist, the assistive technologies group headed by Dr. Nigel Livingston.

    Our work is primarily supported by operating grants from NSERC and CIHR. The interface between our CIHR and NSERC research programs develops from the concept that the processing of information by neural networks can be modified by activity and modulator dependent changes in synaptic connections. We study basic properties of synaptic transmission and apply this understanding to specific circuits and to investigate neural disorders.

    Our NSERC supported research is directed towards understanding the cellular and biochemical basis for activity-dependent and neuromodulator mediated enhancement of neurotransmitter release. Using microfluorometric imaging of fluorescent calcium indicators (fura-2, Ca2+-Green, Fura-Red, Fluo-4 etc.) we study the role of calcium and calcium-dependent processes in presynaptic terminals in modifying the probability of transmitter release in response to action potential activity. Much of this work was conducted in past years using crayfish neuromuscular synapses. Our most recent publication in this area is work by Colin Demill (currently a PhD candidate at U of T) on the interaction between presynaptic inhibition and facilitation at the claw opener synapses, Demill and Delaney, See Publication list.

    We have expanded our work on presynaptic terminals to look at Ca2+ influx in response to action potentials into accessory olfactory bulb mitral cell presynaptic terminals where they form synapses in the amygdala using transport of dextran conjugated Ca2+ indicators. Wanna look?. Presynaptic modulation by various neurotransmitters and the identification of calcium channel subtypes associated with transmitter release and facilitation was studied using this preparation by Sean Mulligan, who has recently joined the faculty of the Dept. of Physiology at the Univ. of Saskatchewan. After leaving my lab Sean did his PhD with Brian MacVicar while Brian was at Univ. of Calgary. Luckily, after many years in exile in the godforsaken frozen Albertan tundra Brian was lured to Vancouver by the siren song of the ever-perky servers on Granville Island: "Sir, if you don't mind sitting in the sunshine while listening to the seagulls fight over your biscotti crumbs I'll bring you that low fat latte out on the deck in just a moment".

    Biophysical modeling studies have examined the consequences of molecular level colocalization of channels and vesicles in presynaptic active zones for Ca2+ diffusion and transmitter release was undertaken by Vahid Shahrezaei using numerical and Monte-Carlo simulations. This work is published: Vesicle PDF1 , Vesicle PDF2 and . Further modeling and experimental work on the effect of reducing the calcium channel density for calcium channel cooperativity at frog neuromuscular junction using w-conotoxin to block channels was recently published by Alex Cao and Vahid Vesicle PDF3 .

    CIHR supported research includes projects integrating synaptic physiology and intrinsic electrophysiological properties of neurons into a network level framework to understand the temporal spatial dynamics that underlie neural processing of sensory signals by the olfactory bulb. For some of this work we have developed a novel in vitro nose-brain preparation that allows brain slice type experiments to be performed in a system where normal patterns of afferent input can be activated by application of odours to the nose. The work involves high speed imaging of Ca2+ and voltage sensitive dye signals from dendrites and/or nerve terminals brain of frogs during stimulation of olfactory epithelia with odours. Complimentary electrophysiological studies are used to relate the activity of individual neurons in the central nervous system (mitral cells and granule cells) to globally distributed oscillatory activity in networks of millions of cells during odour-induced activity. Recordings from mitral and granule cells during odour stimulation of the nose using the in vitro preparation are a significant part of this work. See Delaney and Hall, 1996 and Hall and Delaney, 2002, Davison et al., 2004 for further details. Dr. Tibor Zelles of the Hungarian Academy, Institute for Experimental Medicine in Budapest undertook studies on the active properties of dendrites of granule cells using two photon imaging.

    We have developed methods for selective filling of mitral cell apical dendritic tufts in glomeruli with Ca-Green that allow us to study the function of this superficial dendritic compartment in response to odour stimuli (Delaney et al., 2001). The pharmacology of the odour and shock-evoked Ca2+ transients is under investigation as well as the role of feedback inhibition in controlling the odour-evoked epsp at the distal dendritic input site. Ian Davison completed studies on dopaminergic modulation of transmitter release from mitral cell secondary dendrites using a combination of electrophysiology (whole cell recordings) and 2-photon imaging. See Delaney et al., 2001.

    Dr. Jamie Johnston was supported by CIHR to study biophysical properties and dendritic distribution of low-voltage activated, T-type calcium channels in mouse mitral cells using a combination of whole cell electrophysiology and 2-photon calcium imaging. As of January 2010 he is now a PDF at the MRC in London undertaking studies on retinal synapses. Dr. Adam Fekete joined the laboratory from Budapest in Jan. 2010 to continue eletrophysiological studies of olfactory bulb function.

    Rett Syndrome research: During the past 3 years we have started a program of research on Rett's syndrome using a loss of function mouse model with a mutated non-functional Mecp2 gene (Jaenisch mouse). MECP2 protein normally binds to methylated DNA acting as a transcription repressor to control many genes required for normal development. Loss of function in this gene is the cause of Rett Syndrome a neurodevelopmental disorder leading to severe mental retardation and other systemic dysfunctions primarily in female children. We have crossed these mice with mice that express YFP in subsets of cortical neurons (Feng et al., 2000) to facilitate analysis of neuronal morphologies associated with the Rett phenotype and as a tool to evaluate the success (or failure) of therapeutic interventions. Current work funded by the International Rett Syndrome Foundation is investigating cell autonomous versus non-autonomous effects of this X-linked mutation on synaptic development in cerebellum and hippocampus.

    We are also undertaking a project to develop a liposome-based plasmid insertion of functional MeCP2 gene as a gene replacement strategy. This work is in collaboration with the Centre for Drug discovery and development at UBC. We also have an ongoing biomedical engineering project to develop a wirelessly controlled and powered nerve stimulator, EEG recording device that can be implanted chronically into mice for stroke therapy and Rett Syndrome treatment. These projects are currently supported by CIHR and the Northwest Rett's Syndrome society. Work on the implantable stimulator is conducted in collaboration with Dr. Nigel Livingston's CanAssist assistive technologies group at UVic.

    Selected publications

  • For a full publication list click here

    Zelles T, Boyd JD, Hardy A and Delaney KR 2006 Initiation and propagation of Na+ Ðdependent action potentials in subsets of olfactory granule cell dendrites. J Neurosci 26: 30-40

    Shahrezaei V, Cao A and Delaney KR 2006 Ca2+ from one or two channels controls fusion of a single vesicle at the frog neuromuscular junction. J Neurosci 26:13240-13249

    Charpak S, Mertz J, Moreaux L, Beaurepaire E and Delaney KR 2001 Odour-evoked calcium signals in dendrites of rat mitral cells in vivo Proc.Natl. Acad.Sci.USA 98(3) 1230-1234

    Delaney KR and Hall BJ 1996 An in vitro nose-brain preparation of frog for the study of odour-induced oscillations in olfactory bulb and cortex. J. Neurosci. Meth. 68:193-202

    Feller, MB, Delaney, KR and Tank, DW 1996 Presynaptic calcium dynamics at the frog retino-tectal synapse. J. Neurophys. 76(1) 381-400

    Tank DW, Regehr WG and Delaney KR 1995 A quantitative analysis of calcium dynamics that contribute to short-term synaptic enhancement. J. Neurosci. 15(12): 7940-7952

    Delaney KR and Tank DW 1994 A quantitative measurement of the dependence of short-term synaptic enhancement on presynaptic residual calcium J. Neurosci. 14(10) 5885-5902

    Delaney KR Gelperin A, Fee M, Flores J, Gervais R, Tank DW, and Kleinfeld D 1994 Propagating waves and stimulus-modulated dynamics in an oscillating olfactory network. Proc.Natl. Acad.Sci.USA 91: 669-673