Nocturnal Male Sex Drive in Drosophila

Abstract

Many behaviors and physiological processes including locomotor activity, feeding, sleep, mating, and migration are dependent on daily or seasonally reoccurring, external stimuli. In D. melanogaster, one of the best-studied circadian behaviors is locomotion. The fruit fly is considered a diurnal (day active/night inactive) insect, based on locomotor-activity recordings of single, socially naive flies. We developed a new circadian paradigm that can simultaneously monitor two flies in simple social contexts. We find that heterosexual couples exhibit a drastically different locomotor-activity pattern than individual males, females, or homosexual couples. Specifically, male-female couples exhibit a brief rest phase around dusk but are highly active throughout the night and early morning. This distinct locomotor-activity rhythm is dependent on the clock genes and synchronized with close-proximity encounters, which reflect courtship, between the male and female. The close-proximity rhythm is dependent on the male and not the female and requires circadian oscillators in the brain and the antenna. Taken together, our data show that constant exposure to stimuli emanating from the female and received by the male olfactory and other sensory systems is responsible for the significant shift in intrinsic locomotor output of socially interacting flies.

Chronobiology by moonlight

“…A recent study shows that the flies do not increase activity during full Moon nights in nature [101], most probably because of the lower night-temperatures. The same applies for other nocturnal activities as mating that can be observed under certain conditions in the laboratory [102]. Nevertheless, the laboratory studies showed unequivocally that the fruitflies have the capability to respond to moonlight.…”

Flying the Fly: Long-range Flight Behavior of Drosophila melanogaster to Attractive Odors

“…2). The olfactory system is under circadian clock control (Tanoue et al 2008), sexual activity peaks during the night (Fujii et al 2007), but flies responded to food during the day. Starvation had a decisive effect on attraction to vinegar, in both sexes, irrespective of mating state.…”

Ventral lateral and DN1 clock neurons mediate distinct properties of male sex drive rhythm in Drosophila

“…Although locomotor activity is the most investigated circadian behavior in Drosophila, other behaviors, including courtship and mating (7)(8)(9), are under strong circadian influence. We recently demonstrated that male courtship and locomotor activity exhibit a typical cycling pattern when males are paired with females.…”

“…We recently demonstrated that male courtship and locomotor activity exhibit a typical cycling pattern when males are paired with females. In contrast to single fly locomotor rhythm (SLR), this courtship rhythm, called male sex drive rhythm (MSDR), is characterized by a trough at subjective dusk, followed by a sharp increase of proximity encounters (i.e., courting) that peak during the subjective night (9). per 0 and per S mutant males show arrhythmic and shortperiod (19.5 ± 0.4 h, n = 14) MSDR, respectively, when they are paired with WT females (9).…”