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Oded Mayseless

@mayseless.bsky.social

624 followers 420 following 36 posts

Postdoc in the @schierlab. Visiting scientist @RainerFriedri12. PhD @lab_oren @WeizmannScience. What is the molecular basis of good vs evil? #zebrafish #olfaction

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

10/11 Attractive and aversive odorants recruited separable neuronal populations! Attractive odorants preferentially recruited a dopaminergic short-axon-like interneuron population. Two-photon ablation of TH⁺ interneurons selectively impaired attraction while sparing aversion.

Two time-course plots compare odor-side position in sham and 2-photon-ablated larval zebrafish during odor preference assays. In the top plot, TCA evokes increased attraction in sham larvae, shown by higher relative position during and after odor delivery, while 2p-ablated larvae show reduced attraction. In the bottom plot, ATP evokes avoidance in both sham and 2p-ablated larvae, with both groups shifting away from the odor side. Shaded regions indicate variability, the beige window marks odor delivery, and a dashed horizontal line marks no preference.

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

Mapping these genes in single brains let us impute our scRNA-seq atlas into space with Tangram. This revealed cohesive OB domains: projection neurons tile the outer layer, while interneurons form partially nested inner domains. Not a uniform mosaic: a domain architecture.

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

7/11 Luckily, @yinanwan.bsky.social and Jakob developed a powerful approach for multiplexed whole-mount gene-expression mapping. Sequentially imaging 68 genes in intact larval brains, defined anatomical and transcriptional boundaries of the olfactory bulb at cellular resolution.

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

4/11 Clustering 3D activity maps revealed spatial response patterns. Two were biased by preference: one enriched for aversive odorants, one for attractive odorants, despite chemically diverse members. This suggests bulb activity reflects behavioral preference as well as chemistry

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

3/11 Early olfactory circuits may organize odor information along behaviorally relevant dimensions. To test this in zebrafish larvae, we used pan-neuronal CaMPARI2 to map odorant-evoked activity in freely swimming larvae across a broad spectrum of odorants.

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Oded Mayseless @mayseless.bsky.social · 16/06/2026

2/11 Which odorants do zebrafish larvae like or avoid? We built a flow-based two-choice arena and screened >40 odorant conditions in >1,600 larvae. Attractive odorants induced slow and localized swimming, while aversive odorants drove faster, more erratic movement.

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