Pheromone-mediated command from the female to male clock induces and synchronizes circadian rhythms of the moth Spodoptera littoralis

Identification of Δ9 and Δ11 Desaturases Involved in Sex Pheromone Biosynthesis in Mythimna loreyi (Lepidoptera: Noctuidae)

In moths, sex pheromones are synthesized in pheromone glands (PGs) by a variety of enzymes. Desaturases (DESs) are critical for the introduction of double bonds into pheromones. In Mythimna loreyi, the specific DESs involved in sex pheromone biosynthesis remain unclear. In this study, we identified and characterized 25 putative DESs from the M. loreyi genome. Nineteen of them were expressed in the female PGs, with seven showing significant upregulation in response to pheromone biosynthesis activating neuropeptide (PBAN). RNAi-based knockdown of MlorDES2 significantly reduced the titer of pheromone components by 58.6-85.9%, while knockdown of MlorDES9 specifically reduced the production of (Z)-9-tetradecenyl acetate. Functional verification in yeast revealed that MlorDES2 and MlorDES9 exhibited Δ11 and Δ9 desaturase activities, respectively. Taken together, these results collectively demonstrate that MlorDES2 and MlorDES9 are involved in sex pheromone biosynthesis of M. loreyi, suggesting that DESs could be used as potential targets for pest management.

Regulation of insect cuticular hydrocarbon biosynthesis

Cuticular hydrocarbons (CHCs) play pleiotropic roles in insect survival and reproduction. They prevent desiccation and function as pheromones influencing different behaviors. While the genes in the CHC biosynthesis pathway have been extensively studied, the regulatory mechanisms that lead to different CHC compositions received far less attention. In this review, we present an overview of how different hormones and transcriptional factors regulate CHC synthesis genes, leading to different CHC compositions. Future research focusing on the regulatory mechanisms underlying CHC biosynthesis can lead to a better understanding of how insects could produce dynamic chemical profiles in response to different stimuli.

Protocol for aerial trapping and analyses of candidate pheromone compounds released by moths via gas chromatography-mass spectrometry

Detection of pheromones is pivotal to chemical ecology and agronomy; however, analytic detection of the volatile pheromone components from odorized air is highly challenging. Here, we introduce a protocol for the detection of airborne pheromones from female moths, which are key models for chemosensory studies. We describe a step-by-step guide from pheromone collection to quantitative estimation of pheromone components. We also detail procedures for gas chromatography-mass spectrometry (GC-MS) analysis. This protocol has potential applications beyond chemosensory research, particularly in environmental chemistry. For complete details on the use and execution of this protocol, please refer to Ghosh et al.1.

Sociosexual interactions: A clock synchronized by smell

While the daily rhythmicity of organisms is entrained by several cues, light is thought to be the strongest signal. Surprisingly, a new study in a moth shows that olfactory communication can be even more powerful for synchronization, and, at least to some extent, works across related species.