Insecticide exposure alters flight-dependent gene-expression in honey bees, Apis mellifera

Area of Science:

• * Environmental toxicology
• * Insect physiology
• * Molecular biology

Background:

• * Declining bee populations threaten biodiversity and agriculture.
• * Agrochemicals, particularly neonicotinoids, are suspected contributors to bee losses.
• * Limited data exists linking neonicotinoid exposure to molecular and behavioral impacts in bees.

Purpose of the Study:

• * To investigate the effects of acute thiamethoxam exposure on honey bee (Apis mellifera) flight performance.
• * To analyze the molecular transcription profiles of foraging bees exposed to thiamethoxam.
• * To understand the physiological mechanisms of neonicotinoid-induced impairments.

Main Methods:

• * Controlled experiment using tethered flight mills to measure honey bee flight parameters (distance, duration, speed).
• * Gene expression analysis of key pathways including energy metabolism and hormone regulation.
• * Acute exposure to the neonicotinoid thiamethoxam.

Main Results:

• * Thiamethoxam exposure induced hyperactive flight behavior in bees.
• * Significant downregulation of genes involved in oxidative phosphorylation was observed.
• * Molecular disruptions were exacerbated during flight, indicating combined stress effects.

Conclusions:

• * Acute thiamethoxam exposure disrupts honey bee energy metabolism at the molecular level.
• * Pesticide exposure combined with physical exertion poses a significant threat to bee foraging and fitness.
• * Findings provide insights into the molecular basis of neonicotinoid toxicity in bees.