The 57th Conference of The Zoological Society of Israel

Various behavioral aspects in insects are controlled by an endogenous clock and exhibit circadian rhythmicity. To keep track of local time, these clocks use a variety of time cues such as light–dark, temperature, food availability and social interaction cycles. Social communication is an integral component in insect behavior, particularly for mate searching and reproduction. T. castaneum is one of the most damaging cosmopolitan pest of flour and other stored food products. It’s aggregation pheromone, 4,8-dimethyldecanal (DMD), produced by the males, attracts both conspecific males. The daily ryhthmicity in pheromonal communication is an intergral component of circadian clock in insects. Until now only a one way effect of circadian clock on the pheromonal communication has been studied. Therefore our obective was to study wheather in aggregative species like T. castaneum a feedback meachanism of pheromone affecting the circadian rhythmicity occurs. We studied one of the major clock genes involved in the endogenous control of circadian rhythms in T. castaneum,TcTimeless.Our results demonstrate that the pheromone DMD alter the expression patterns of TcTimeless in beetles heads(GLM: Z=5.48, P<0.0001). These results demonstrate, for the first time, circadian clock gene regulation by an aggregation pheromone and provide new insights into how social signals are potentially integrated at the circadian clock molecular level.