Research in our laboratory uses various molecular, genetic and electrophysiological techniques to study the functional roles of potassium channels in the nervous system with particular emphasis on the inwardly rectifying (Kir) channels. Molecular techniques are used to study the cellular and subcellular distribution of Kir channels and their functional and biophysical properties on expression in heterologous systems such as Xenopus oocytes or mammalian cell lines. In addition, the laboratory has generated mice carrying targeted deletions of specific Kir channel genes to determine their function "in vivo". Among these, the Kir4.1 channel "knock out" mice display motor, sensory deficits and shorter life span. We are currently investigating the role of Kir4.1 channels in regulation of extracellular potassium in retina and other tissues.
Another major effort in our laboratory is to study the form and function of intrinsically photosensitive ganglion cells in the mammalian retina. Within the retina of the vertebrate eye there are photoreceptors that capture light to regulate non-image forming visual processes such as day–night rhythms and the narrowing and widening of the pupil. To capture light, these special cells called intrinsically photoreceptive retinal ganglion cells, require pigments called melanopsins, similar to the opsins that the rod and cone cells use for turning light into vision. While the development of cones and rods has been extensively studied, much less is known about the development of melanopsin-expressing ganglion cells. Our lab aims to determine how melanopsin-expressing ganglion cells develop from newborn to adult mouse stages.