A kiss for daily and seasonal reproduction.

ABSTRACT

Reproduction is a fundamental biological function ensuring individual descendant survival and species perpetuity. It is an energy-consuming process, and therefore, all underlying mechanisms have to work in synchrony to ensure reproductive success. Synchronization of reproductive activity with the best time of the day or the year is part of such adaptive processes. Recently, a neuropeptide named kisspeptin, synthesized in two discrete hypothalamic nuclei, the anteroventral periventricular nucleus and the arcuate nucleus, has been demonstrated to be a potent stimulator operating upstream of the gonadotropic axis. In this review, we show how kisspeptinergic neurons integrate daily and seasonal time cues to synchronize reproductive activity with the cycling environment.