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Biology subjects

Maniere, G.

Publications and source records attributed to Maniere, G..

2 recordsLinked to original sources

Evolutionary divergence in sugar valuation shifts Drosophila suzukii oviposition choice towards ripe fruit

Behavior evolution can promote the emergence of agricultural pests via ecological niche changes. The underlying neuronal mechanisms are poorly understood. We investigate the chemosensory changes underlying the evolutionary shift of oviposition substrate of the pest Drosophila suzukii from rotten to ripe fruits. Using a model substrate for fermented fruits and genetic manipulations, we show that an increase in valuation of fruit sugars during oviposition decisions drives D. suzukii to oviposit on ripe fruits as opposed to the model D. melanogaster which prefers rotten fruits. Inter-species comparative in vivo calcium imaging of sugar Gustatory Receptor Neurons suggests that increased sugar valuation in D. suzukii is related to neuronal sensitivity changes at multiple levels of the oviposition circuitry. Our results show that the tuning of sugar valuation has contributed to the evolution of oviposition preference on ripe fruit of D. suzukii.

evolutionary biology↗

Bacteria-derived peptidoglycan triggers an NF-kB dependent response in Drosophila gustatory neurons

Probing the external world is essential for eukaryotes to distinguish beneficial from pathogenic microorganisms. If it is clear that this task falls to the immune cells, recent work shows that neurons can also detect microbes, although the molecules and mechanisms involved are less characterized. In Drosophila, detection of bacteria-derived peptidoglycan by pattern recognition receptor (PRR) of the PGRP family expressed in immune cells, triggers NF-{kappa}B/IMD dependent signaling. We show here that one PGRP protein, called PGRP-LB, is expressed in some probosciss bitter taste neurons. In vivo calcium imaging reveals that the PGRP/IMD pathway is cell-autonomously required in these neurons to transduce the PGN signal. We finally show that NF-{kappa}B/IMD pathway activation in bitter neurons influences fly behavior. This demonstrates that flies use the same bacterial elicitor and signaling module to sense bacterial presence via the peripheral nervous system and trigger an anti-bacterial response in immune-competent cells.

neuroscience↗