Professor Li Sheng and Associate Professor Li Na from the School of Life Sciences at South China Normal University, in collaboration with Professor Pan Yufeng from Southeast University, have unveiled the molecular mechanism underlying the mating behavior of male American cockroaches, regulated by two types of sex pheromone components. The findings were recently published online in a lengthy article in the English edition of "Science China: Life Sciences".
"We dissected the molecular mechanism of mating in American cockroaches and found that two sex pheromone components, periplanone-A (PA) and periplanone-B (PB), jointly regulate male roaches' courtship mating behavior through two olfactory receptors, OR53 and OR100," said Professor Li Sheng, the corresponding author of the paper, to "Science China Daily".
The mating communication behavior of the American cockroach involves two types of sex pheromones and their pathways of reception through two odorant receptors.
Volatile sex pheromones play a crucial role in sexual communication between males and females, widely present in animals including insects, capable of attracting potential mates over long distances and typically detected by specialized odorant receptors in males. Female American cockroaches produce and release two components of sex pheromones, PB and PA, after reaching sexual maturity. Previous research has demonstrated that PB is the primary sex attractant, capable of attracting males, but the interaction between PB and PA in regulating sexual behavior remains unclear.
This study, for the first time, found that PB can attract adult male American cockroaches over long distances, while PA may counteract the attractiveness of PB. Researchers observed and recorded mating behavior between male and female American cockroaches through various behavioral tests. They also conducted electrophysiological, gender- and age-specific transcriptomic, Drosophila genetics, and RNAi knockdown experiments to identify OR53 as the receptor for PA/PB and OR100 as the receptor for PA. They used fluorescent in situ hybridization and single-cell sequencing to localize the expression of OR53 and OR100 in the two types of sensilla in the male antennae.
This study focused on the molecular mechanisms of olfactory perception in mating between male and female American cockroaches, analyzing behavior, electrophysiology, and transcriptomics. It identified two odorant receptors, OR53 and OR100, acting as receptors for PB/PA and PA, respectively. OR53 and OR100 are primarily expressed in the antennae of sexually mature males, and their expression levels are regulated by gender differentiation pathways and nutrient response signals. The cellular localization of OR53 and OR100 in the male antennae further reveals the coordination of two receptors in a complex two-sex pheromone-two-receptor pathway to regulate sexual behavior in American cockroaches.
These findings demonstrate the different functions of two components of sex pheromones, identifying their receptors and regulatory mechanisms, which play a role in male-specific and age-related sexual behaviors and may provide new guidance for pest management strategies.
Related paper information: https://doi.org/10.1007/s11427-023-2548-3
