Biology subjects

Xu, Y. Y. J.

Publications and source records attributed to Xu, Y. Y. J..

3 recordsLinked to original sources

bioRxiv2025

cAMP-related second messenger pathways modulate hearing function in Aedes aegypti mosquitoes

The powerful ears of male Aedes aegypti mosquitoes facilitate identification and localization of mating partners via detection of female flight tones. Male hearing function is modulated by the efferent release of neurotransmitters, though the secondary mechanisms underlying this modulation remain unclear. Here, we investigated these mechanisms using octopamine as a model, as octopamine modulates hearing function and the erection status of fibrillar hairs lining male ears. We found that pharmacological interference with octopamine receptors alters hearing function at multiple levels and identified the second messenger cAMP as likely mediating these changes. Furthermore, the erection status of male ear fibrillar hairs could be altered by targeting specific sub-types of octopamine receptors, but these changes were not linked to changes in ear frequency tuning. Finally, we suggest that octopamine 2 receptors linked to fibrillar hair erection may not always produce functional proteins across species, with downstream implications for hearing behaviors. HighlightsO_LIOctopamine and its receptors are found throughout Aedes aegypti mosquito ears C_LIO_LIPharmacological interference with octopamine receptors modulates hearing function C_LIO_LIModulating levels of the second messenger cAMP also alters hearing function C_LIO_LIEar frequency tuning does not correlate with the erection of hairs lining male ears C_LI

neuroscience↗

bioRxiv2024

Sexually dimorphic auditory representation in Aedes aegypti brains

Male attraction to female flight sounds is a vital, reproducible component of courtship in many species of mosquitoes; however, female acoustic behaviours have proven challenging to define. To investigate sexual dimorphisms in acoustic behaviours, previous reports have largely focused on differences in mosquito peripheral ear anatomy and function. Whilst molecular investigations have recently begun on the auditory periphery, sexual dimorphisms in central processing of acoustic information have not yet been explored. Here we used a combination of neurotracing, calcium imaging and molecular analyses to examine sexual dimorphisms in auditory processing in the yellow fever mosquito Aedes aegypti. We identified shared and dimorphic neurons connecting male and female ears to the primary auditory processing centre in the brain, and defined multiple distinct neuronal clusters based on responses to auditory stimulation. We finally used transcriptomic and proteomic analyses to investigate the molecular factors underlying these differences, with motile ciliary-related terms significantly enriched in males.

neuroscience↗

bioRxiv2024

The voltage-gated potassium channel Shal (Kv4) contributes to active hearing in Drosophila

The full complement of ion channels which influence insect auditory mechanotransduction, and the mechanisms by which their influence is exerted, remain unclear. Shal (Kv4), a Shaker family member encoding voltage-gated potassium channels in Drosophila melanogaster, has been shown to localize to dendrites in some neuron types, suggesting a potential role for Shal in Drosophila hearing, including mechanotransduction. A GFP-protein trap was used to visualize the localization of the Shal channel in Johnstons organ neurons responsible for hearing in the antenna. Shal protein was localized to the cell body and the proximal dendrite region of sensory neurons, suggesting its involvement not only in general auditory function, but specifically in mechanotransduction. Electrophysiological recordings conducted to assess neural responses to auditory stimuli in mutant Shal flies revealed significant decreases in auditory responses. Laser Doppler Vibrometer recordings indicated abnormal antennal free fluctuation frequencies in mutant lines, indicating an effect on active antennal tuning, and thus active transduction mechanisms. This suggests that Shal participates in coordinating energy-dependent antennal movements in Drosophila that are essential for tuning the antenna to courtship song frequencies. Significance StatementThe study of fruit fly hearing has revealed mechanosensitive ion channels that participate in mechanotransduction, and as in mammalian hearing, energy-dependent mechanisms actively amplify and tune auditory processes. Identifying distinct roles played by different ion channels is essential to better understand this process. Here, we explore the influence of a specific voltage-gated potassium channel, Shal, on fly hearing, and find that it affects specific parts of the mechanotransduction process. Our research uncovers Shals localization in sensory dendrite regions of auditory neurons, where it contributes to shaping mechanotransduction and active antennal tuning. Understanding Shals involvement in auditory function and mechanotransduction deepens our knowledge of fly hearing and unveils a key player in the coordination of energy-dependent active antennal movements.

neuroscience↗