Dr. Georg Nagel gives talk: Light-manipulation using microbial photoreceptors

Centre for Synthetic Biology and FOBI are honored to present guest speaker professor Dr. Georg Nagel of the Institute of Molecular Plant Physiology and Biophysics (Botany 1) at University of Würzberg.

On August 8th at 1 pm, he will give the talk entitled:

"Application of microbial photoreceptors to light-manipulate cells and live animals"

Abstract
Photoreceptors from green algae were molecularly identified in recent years. We could show that they are ideal tools to manipulate animal cells by illumination. The Channelrhodopsins from the unicellular green alga C. reinhardtii are light-gated cation channels which allow fast light-induced depolarization. Neuronal expression of ChR2 yields light-induced action potentials and light-manipulated behaviour in C. elegans whereas neuronal expression of the light-activated chloride pump halorhodopsin from the archaeum Natronomonas pharaonis allows light-induced silencing of neurons. We expressed the photoreceptor of the green unicellular flagellate E. gracilis – a flavoprotein that is a photo-activated adenylyl cyclase (PAC), composed of PACa and PACb - in oocytes of X. laevis where it generates reversible light-dependent [cAMP] increase. PACa shows a notable adenylyl cyclase activity in the dark and light-stimulated activity is much higher than that of PACb. Expression of PACa in neurons of D. melanogaster showed strong reversible effects of blue light on the behaviour of these flies. Mutants of PACa prove an intermolecular dimerization of two different cyclase domains (C1 and C2 on PACa) to form a functional cyclase.

Directions: The talk takes place on the 8th of August at 1 pm in M117 at Department of Plant Biology and Biotechnology, Thorvaldsensvej 40, opg. 10, 1., 1871 Frederiksberg