Sensory neuron population expansion enhances odor tracking without sensitizing projection neurons

janelia7_blocks-janelia7_biblio_header | block

bioRxiv. 2024 Feb 28;. doi: 10.1101/2023.09.15.556782

Sensory neuron population expansion enhances odor tracking without sensitizing projection neurons Stern Lab

Takagi Suguru, Sancer Gizem, Abuin Liliane, Stupski David, Arguello Roman, Prieto-Godino Lucia, Stern David, Cruchet Steeve, Álvarez-Ocaña Raquel, Wienecke Carl, van Breugel Floris, Jeanne James, Auer Thomas, Benton Richard

janelia7_blocks-janelia7_biblio_abstract | block

Abstract

The evolutionary expansion of sensory neuron populations detecting important environmental cues is widespread, but functionally enigmatic. We investigated this phenomenon through comparison of homologous neural pathways of Drosophila melanogaster and its close relative Drosophila sechellia, an extreme specialist for Morinda citrifolia noni fruit. D. sechellia has evolved species-specific expansions in select, noni-detecting olfactory sensory neuron (OSN) populations, through multigenic changes. Activation and inhibition of defined proportions of neurons demonstrate that OSN population increases contribute to stronger, more persistent, noni-odor tracking behavior. These sensory neuron expansions result in increased synaptic connections with their projection neuron (PN) partners, which are conserved in number between species. Surprisingly, having more OSNs does not lead to greater odor-evoked PN sensitivity or reliability. Rather, pathways with increased sensory pooling exhibit reduced PN adaptation, likely through weakened lateral inhibition. Our work reveals an unexpected functional impact of sensory neuron expansions to explain ecologically-relevant, species-specific behavior.

node:body | entity_field

bioRxiv preprint https://www.biorxiv.org/content/early/2024/02/28/2023.09.15.556782

Main Menu (Mobile)- Block

Main Menu - Block

Sensory neuron population expansion enhances odor tracking without sensitizing projection neurons

Abstract

Janelia Authors