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Reposted by Jan M. Ache

Greg Jefferis @jefferis.bsky.social · 3d

Exciting news for #drosophila #connectomics and #neuroscience enthusiasts: the Drosophila male central nervous system connectome is now live for exploration. Find out more at the landing page hosted by our Janelia FlyEM collaborators www.janelia.org/project-team....

Male CNS Connectome

A team of researchers has unveiled the complete connectome of a male fruit fly central nervous system —a seamless map of all the neurons in the brain and nerve cord of a single male fruit fly and the ...

www.janelia.org

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Reposted by Jan M. Ache

Chris J Dallmann @chrisjdallmann.bsky.social · 21d

Now out in @nature.com: Our study discovering a neural circuit in Drosophila that predictively inhibits proprioceptor axons during voluntary leg movements, such as walking and grooming. www.nature.com/articles/s41...

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Jan M. Ache @jan-ache.bsky.social · 23d

Couldn’t be more excited about this paradigm shifting result.

Person standing in a park with a stroller while enjoying a tasty Dürüm.

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Reposted by Jan M. Ache

Gizem Özdil @gzmozd.bsky.social · 26d

🪰 How do dozens of tiny fly muscles cooperate to move a leg?

We’re excited to share the first 3D, data-driven musculoskeletal model of Drosophila legs based on Hill-type muscles, running in OpenSim and MuJoCo simulation environments.

Preprint: arxiv.org/abs/2509.06426

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The Transmitter @thetransmitter.bsky.social · Aug 13

FlyBase, a Drosophila database, will lose a third of its team in early October because the Harvard grant that covered the employees’ salaries was canceled. Scientists warn that losing FlyBase could devastate fly research.

By @claudia-lopez.bsky.social

www.thetransmitter.org/community/ha...

Harvard University lays off fly database team

The layoffs jeopardize this resource, which has served more than 4,000 labs for about three decades.

www.thetransmitter.org

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Jan M. Ache @jan-ache.bsky.social · Jul 28

We thank @dfg.de and the #NeuroNex program for generously funding our work, and our neighbours and colleagues at @uni-wuerzburg.de, especially the Department of Neurobiology and Genetics (Charlotte Förster, Chris Wegener, and @silkesachse.bsky.social).
Stay tuned - more walking papers on the way...

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Jan M. Ache @jan-ache.bsky.social · Jul 28

This study was a team effort, with some surprises and directional changes on the way. I am grateful to the entire crew, especially Stefan & Sander, Fathima, Feffo, Mert, and Aleyna from my lab, Adrián and @postpop.bsky.social from the Clemens Lab, and Axel and Ansgar from the Büschges lab.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Both MDN and DopaMeander are gated out (switched off) during flight. Showing that behavioral state-dependent gating occurs simultaneously across levels of motor control and is bidirectional in nature, allowing the specific boosting of motor control modules in the appropriate behavioral context.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Finally, we leveraged the fact that we identified neurons controlling walking across hierarchical levels to ask how the brain ensures that appropriate motor output is generated in different behavioral states. To do so, we recorded MDN and DopaMeander in flies transitioning into and out of flight.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

DopaMeander, in contrast, contributes to forward walking, but its activity is particularly linked to turning in the ipsiversive direction - so that the right DopaMeander contributes to rightward turns, and the left DopaMeander to leftward turns...

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Jan M. Ache @jan-ache.bsky.social · Jul 28

We quantified this by building linear-nonlinear models which estimate how, precisely, each neuron controls walking parameters. It turns out MDN does not simply ‘switch’ the walking direction but encodes a backward walking drive that increases from forward walking, to stopping, to backward walking.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

We then performed patch-clamp recordings from DopaMeander and MDN in spontaneously walking flies. DopaMeander is more active during forward walking, whereas MDN is more active during backward walking – as predicted from the phenotypes of both neurons. Hence, they control opposite walking regimes.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Why get excited about this? Dopamine is tightly linked to motor control in the vertebrate nervous system. In flies, dopamine is strongly linked to learning and memory and decision-making processes, but less so to motor control or walking (one great exception here: tinyurl.com/3xx88j37).

Locomotor and olfactory responses in dopamine neurons of the Drosophila superior-lateral brain

Marquis and Wilson describe the physiology of three types of dopamine neurons in the Drosophila brain. They show that all these neurons are correlated with the fly’s walking speed, and some also respo...

tinyurl.com

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Activation, silencing and stochastic labeling experiments reveal that DopaMeander drives forward walking and turning. It is also required for fast walking - flies with silenced DopaMeander walk and turn much less when facing an optomotor stimulus, which induces walking in circles in controls.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Here, we identified a novel, dopaminergic cell type in the brain which drives forward walking – DopaMeander. Connectome analyses reveal DopaMeander modulates a circuit in a specific brain region (the AVLP), which integrates mechanosensory cues from the legs, and includes walking-related neurons.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Next, we turned our attention to forward walking – the preferred way for flies to get around in the world (some argue ‘flies’ should really be called ‘walks’). Forward walking is more versatile and accordingly controlled by larger populations of neurons across complex sensorimotor hierarchies.

a man in a suit and hat is walking down a hallway carrying a briefcase

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Jan M. Ache @jan-ache.bsky.social · Jul 28

We demonstrate that this switch in walking direction is driven by Moonwalker Descending Neurons (MDNs) – which were originally discovered by @salilbidaye.bsky.social. Our patch-clamp recordings show MDNs encode antennal touch. MDNs are also required for antenna-driven backward walking.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

First, we looked at backward walking, which typically occurs in response to a threat – or when animals bump into an object or a conspecific. To simulate the sensory stimulus of bumping into something, we poked the antennae of forward walking flies – and found that they reverse walking direction.

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Jan M. Ache @jan-ache.bsky.social · Jul 28

Preprint Alert! Walking mostly feels natural and easy to us - but the neuronal control of walking is actually incredibly complex. We leveraged the fruit fly as a genetically tractable animal model with a compact nervous system to ask how the brain controls walking direction: tinyurl.com/flywalk. 🧵..

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Kevin Mitchell @wiringthebrain.bsky.social · Jul 16

This isn't a coincidence, IMO. The fly community is generally super rigorous - because there are so many tools and techniques available, people expect you to really nail things in order to get published (and keep getting funded)

W. Brent Derry @wbderry.bsky.social · Jul 16

Model organism communities are fantastic. Good work, "Drosophilists"! www.nature.com/articles/d41...

Giant study finds a research field that’s mostly reproducible

Researchers assessed more than 1,000 results from fruit-fly immunity research published between 1959 and 2011. The majority of findings look verifiable.

www.nature.com

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Carolina Rezaval @crezaval.bsky.social · Jun 26

We're hiring! Two exciting opportunities in our Lab @unibirmingham.bsky.social

Come work with us on decision-making and neural circuits in Drosophila. Please share!

Senior Research Technician + Postdoctoral Research Fellow

Deadline: 10 July

More info here: www.rezavallab.org

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Jan M. Ache @jan-ache.bsky.social · Jun 26

Very happy to share that the awesome @merterginkaya.bsky.social was awarded a @dfg.de #WalterBenjamin scholarship for his postdoc project on mechanisms for action-selection in visual sensorimotor pathways. The more Mert the better. 🎉

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Jan M. Ache @jan-ache.bsky.social · Jun 21

It’s a wrap for the 2025 Crete Fly Circuits meeting! Huge thanks to our friends at the OAC for hosting us, our fantastic speakers for sharing their latest and greatest unpublished works, and to Eugenia, Marion, Nilay, and Richard for the fun we had organizing this. See you all in 2027!

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Stephen F. Goodwin @stephenfgoodwin.bsky.social · Jun 9

New preprint from lab: www.biorxiv.org/content/10.1... Sexual dimorphism arises not through wholesale transcriptional reprogramming, but via selective sex-specific survival of neurons defined by birth order and shared developmental programs.

A Role for Exaptation in Sculpting Sexually Dimorphic Brains from Shared Neural Lineages

Sex differences in behaviours arise from variations in female and male nervous systems, yet the cellular and molecular bases of these differences remain poorly defined. Here, we take an unbiased, sing...

www.biorxiv.org

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Jan M. Ache @jan-ache.bsky.social · Jun 8

The sky knows what’s up. Happy #pridemonth! 🌈