Mathematical Biology Seminar|
David Krizaj, Opthalmology, University of Utah,
Wednesday Feb. 25, 2008
3:05pm in LCB 215
"Spatial and temporal regulation of
intracellular calcium in photoreceptors"
The calcium ion plays a central role in photoreceptor function: it
controls both photoreceptor input (represented by the
phototransduction cascade) and its output (represented by the rate of
neurotransmitter release); it has numerous other tasks as well,
including regulation of gene expression and cytoskeletal dynamics. It
is obvious that the ability of calcium to do its work in rods and
cones depends on positioning of its influx, clearance and
sequestration mechanisms represented by assorted channels and pumps.
My presentation has two aims. First, I will show how we characterized
some of the important players in calcium regulation in rod and cone
photoreceptors. This will include a demonstration of the methods we
use in the lab, from Ca imaging, field potential recordings and patch
clamp to PCR, immunolocalization and RNAi. In the second part I will
discuss the issues that, in my mind, are still unresolved with respect
to Ca signaling in photoreceptors. I will try to emphasize questions
that could benefit from biophysical analysis such as the relationship
between local and global Ca signaling, diffusion and buffering.