Imidacloprid susceptibility is linked to life history regulation in honey bees (Apis mellifera)

ABSTRACT: The western honey bee (Apis mellifera) often encounters chemical stressors in the form of phytochemicals, or pesticide residues. The first line of defense against these agrochemicals is constitutively expressed detoxification enzymes such as cytochrome P450s.Honey bees with lower levels of constitutively expressed enzymes experience greater immediate stress, which can lead to death, sub-lethal effects, and precocious foraging, if nursing. Precocious foragers are young, less developed honey bees that are recruited into the foraging population, whereas normal-aged foragers are much older. These precocious foragers are less capable flyers, and are more likely to die during their flights, which can in turn further stress the colony due to reduced food stores. In our study, we hypothesize that chemical stress sensitivity is directly linked to the onset of precocious foraging. Additionally, we believe that precocious foragers are less suited for foraging due to their rushed development, and are likely more transcriptionally similar to nurses instead of older foragers. We measured the survival of honey bees taken from 26 different colonies when exposed to a chemical stressor over 48 hours. Honey bees from each of these colonies were also all added to the same colony, and we measured the age and number of foragers from each colony over a 2-week period. Lastly, we performed transcriptomics of young and old nurses and foragers. Our results suggest that chemical stress tolerance was linked to the honey bee’s origin colony. Moreover, we found no significant correlation of the honey bees’ chemical tolerance to the age at which they began foraging. Rather, we found that bees from more tolerant colonies exhibited lower volumes of foraging by two weeks. Furthermore, transcriptomic analysis showed that precocious foragers exhibited global gene expression patterns more closely aligned with nurses than with older foragers, reinforcing age as the primary determinant of gene expression profiles. Susceptible bees displayed distinct expression profiles compared to more tolerant ones across different life stages, with notable overlap in genes encoding cytochrome P450e and a vitellogenin receptor, highlighting their potential roles in stress response and behavioral maturation.

ORGANISM(S): Apis mellifera

PROVIDER: GSE300082 | GEO | 2026/03/17

REPOSITORIES: GEO