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Abstract Artificial light at night (ALAN) is an increasingly important form of environmental disturbance as it alters Light:Dark cycles that regulate daily and seasonal changes in physiology and phenology. The Northern house mosquito (Culex pipiens) and the tiger mosquito (Aedes albopictus) enter an overwintering dormancy known as diapause that is cued by short days. These two species differ in diapause strategy:Cx. pipiensdiapause as adult females whileAe. albopictusenter a maternally-programmed, egg diapause. Previous studies found that ALAN inhibits diapause in both species, but the mechanism is unknown. As the circadian clock is implicated in the regulation of diapause in many insects, we examined whether exposure to ALAN altered the daily expression of core circadian cloc genes (cycle,Clock,period,timeless,cryptochrome 1,cryptochrome 2, andPar domain protein 1) in these two species when reared under short-day, diapause-inducing conditions. We found that exposure to ALAN altered the abundance of several clock genes in adult females of both species, but that clock gene rhythmicity was maintained for most genes. ALAN also had little effect on clock gene abundance in mature oocytes that were dissected from femaleAe. albopictusthat were reared under short day conditions. Our findings indicate that ALAN may inhibit diapause initiation through the circadian clock in two medically-important mosquitoes.
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Sexually dimorphic and clock gene-specific effects of artificial light at night on Drosophila behavioural rhythms
Light pollution is a major anthropogenic environmental change and a significant threat to ecosystems. Among other detrimental effects on physiology, artificial light at night (ALAN) disrupts circadian rhythms in a wide range of species. However, the underlying neuronal and genetic mechanisms remain poorly understood. Here, we show in Drosophila that the loss of the circadian clock gene period exacerbates the ALAN-induced shift towards nocturnal behaviour, with a more pronounced effect on males. In contrast, the loss of cycle has no such effect on males or females; cyc null mutants are nocturnal under standard light‒dark cycles, and their activity and sleep profiles are minimally or not affected by ALAN exposure. CRISPR-Cas9 knockout of period n most clock neurons resembles the null mutant phenotype. Our results show that mutations in components of the positive and negative limbs of the circadian clock result in distinct responses to nocturnal light and highlight the role of genetic factors in modulating behavioural plasticity in response to environmental perturbations.
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- PAR ID:
- 10663111
- Publisher / Repository:
- The Royal Society Publishing
- Date Published:
- Journal Name:
- Proceedings of the Royal Society B: Biological Sciences
- Volume:
- 292
- Issue:
- 2053
- ISSN:
- 1471-2954
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1098/rspb.2025.1170
