Dr Mikko Juusola: Experience-dependent plasticity

Rearing Conditions Tune Photoreceptors' Signalling

After demonstrating that some changes in the response dynamics of mutant photoreceptors result from a compensatory increase of different conductances, we began to study if the developmental environment could also affect functional expression, and thus the signalling properties of adult photoreceptors. The flies were reared under two different light regimes: 12:12 light/dark cycle or in constant darkness, and further exposed to either light or darkness two hours prior the experiment. The results were clear. There are very large differences in signal and noise of the photoreceptor responses between the fly groups (Wolfram & Juusola, 2004). These characteristics indicated that fly photoreceptors could be tuned by recent light exposure within a limit set by the developmental light experience of the fly. We are working currently to resolve the molecular mechanisms responsible for these changes.