People
Michael Jonz
Research
Sensory systems in vertebrates, ion channels, oxygen chemoreceptors, retinal neurons, zebrafish.
Dr. Jonz’s research interests include the morphology, neurophysiology, and development of sensory systems in vertebrates. He currently uses two main experimental preparations to address issues such as sensory transduction and synaptic transmission.
1. Cellular mechanisms of O2 chemoreception
Specialized O2 chemoreceptors in vertebrates “sense” changes in blood or environmental O2 and initiate adaptive physiological responses via the nervous system. Using aquatic vertebrates as animal models, Dr. Jonz and his group isolate O2 chemoreceptors from the gills and perform patch-clamp electrophysiological recordings in vitro to study membrane ion channels and their potential roles in O2 sensing. The underlying sensory neural pathways and neurochemical components in adult and developing vertebrates are also of interest, and are studied using high-resolution confocal microscopy.
2. Ion channel modulation and feedback in the outer retina
Horizontal cell neurons of the vertebrate retina form synaptic connections with cone photoreceptors and play a major role in such visual processes as contrast enhancement and colour opponency. The activity of many cells in the retina, including horizontal cells, is dependent on extracellular pH. Dr. Jonz studies the modulation of ion channels by protons (H+) in horizontal cells, and potential mechanisms of feedback in the outer retina.
Training
Dr. Jonz received his honours B.Sc. in Biology from the University of Guelph in 1997. Michael then began graduate work at Brock University on nematode chemoreceptors with Joffre Mercier and Ekaterini Riga and received his M.Sc. in 2000. He then moved on to McMaster University to work under the supervision of Colin Nurse, and earned his Ph.D. in 2004 in the fields of neurobiology and comparative physiology. Dr. Jonz’s Ph.D. thesis described the morphology, innervation, and development of O2 chemoreceptors in the zebrafish gill, and provided the first characterization of an O2-sensitive ion channel in these cells. He then moved to Halifax to work with Steven Barnes as a postdoctoral fellow at Dalhousie University in the Faculty of Medicine where his work was focused on the characterization of ion channel modulation by H+ in retinal horizontal cells. Dr. Jonz joined the Department of Biology at the University of Ottawa in 2007 as an Assistant Professor.
Dr. Jonz is the past recipient of a research fellowship from the Nova Scotia Health Research Foundation, and is currently a member of the Editorial Board of Acta Histochemica.