Séminaire du LPTMS: J. Reingruber

Phototransduction in rod and cone photoreceptors

Jürgen Reingruber, Ecole Normale Superieure

Vision is initiated with the absorption of light by rod and cone photoreceptors in the retina, which are highly specialized sensory cells. Rods sustain monochrome night vision, while cones maintain colorful day vision. Phototransduction is the process by which light is transformed into an electrical signal in photoreceptors, a topic that still moves at the forefront of signal transduction research.
In this talk I will first give an introduction to phototransduction in rod and cone photoreceptors. Despite of decades of intense research, an overall biophysical model that integrates and explains all the experimental data is still missing. For example, it was realized already 70 years ago that rods are so sensitive that they can reliably detect the absorption of a single photon. However, up to today it is still not fully understood what determines the high fidelity of a rod cell.
Based on novel experimental recordings of the background noise and single photon response in genetically modified mouse rods (collaboration with G. Fain (UCLA)), I will present recent results obtained from a combined effort between biophysical modeling, mathematical analysis and numerical simulations to understand the molecular mechanisms underlying the single photon response.
Finally, I will briefly discuss the importance of molecular modeling to improve new optogenetic treatments of retinal diseases caused by photoreceptor degeneration (collaboration with S. Picaud (Institut de la Vision, Paris)).

Date/Time : 12/06/2012 - 11:00 - 12:00

Location : LPTMS, salle 201, 2ème étage, Bât 100, Campus d'Orsay

Upcoming seminars