#lablife
a rare begining of the week to have good news on technical success: #Drosophila#Electroretinogram is starting to produce good data; DART system from @BFKlab is running too, so we can finally probe arousal threshold again!
Loved the ending of the discussion, on why the head-direction circuit is organised in 8 columns:
"not all numbers of neurons enable a working circuit. The circuits for N=2 and N=4 are degenerate – either producing a single dimensional encoding, or two disconnected circuits that do not enforce the required circular topology. N=8 is the smallest power of two that could result in a non-degenerate circuit. This hints at the possibility that the eight-column architecture is not a chance evolutionary artefact, but rather that it is the genetically simplest circuit capable of performing heading integration."
We wrote a "little" review about odor coding across phyla, now out in @nature review neuroscience
Enjoy reading here: https://rdcu.be/dJgF7
With Kara Fulton, David Zimmerman, Aravi Samuel and @Datta_Lab
"A petavoxel fragment of human cerebral cortex reconstructed at nanoscale resolution" by Shapson-Coe et al. 2024 (Lichtman lab).
The reconstruction at its current state is already useful and very interesting. Here is to hoping the authors will put in more time and resources to further polish it.
A remarkable finding from Shapson-Coe et al. 2024 paper on human brain #connectomics: the presence of canalized connections in the human brain cortex. Canalized in the Kauffman boolean networks sense [1], which here means: among the many synaptic inputs that any one neuron integrates, some are far stronger (by number of synapses) than the rest.
[1] Canalisation as a term was introduced by Waddington in 1942 in the context of genetics to mean "some phenotypic traits are very robust to small perturbations" https://en.wikipedia.org/wiki/Canalisation_(genetics)
“Romantic engagement can bias sensory perception. This 'love blindness' reflects a common behavioral principle across organisms: favoring pursuit of a coveted reward over potential risks.”
“we discover a dopamine-governed filter mechanism in male Drosophila that reduces threat perception as courtship progresses. We show that during early courtship stages, threat-activated visual neurons inhibit central courtship nodes via specific serotonergic neurons. This serotonergic inhibition prompts flies to abort courtship when they see imminent danger. However, as flies advance in the courtship process, the dopaminergic filter system reduces visual threat responses, shifting the balance from survival to mating.”
I'm happy to present the last paper from my thesis!
Lisa Li and I set out to build a model of fly walking which is based on 3D kinematics data, handles perturbations, and includes sensorimotor delays. (This was supervised by Bing Brunton and @tuthill )
We set up a new modeling framework, generated fly walking with kinematics matched to real data, a simple metric for quantifying similarity of trajectories, and found constraints on delays for robust walking!
“Feeding-state dependent modulation of reciprocally interconnected inhibitory neurons biases sensorimotor decisions in Drosophila”, by Eloise de Tredern et al. 2024 (Tihana Jovanic’s lab) https://doi.org/10.1101/2023.12.26.573306
“the competition between different aversive responses to mechanical cues is biased by feeding state changes. We found that this is achieved by differential modulation of two different types of reciprocally connected inhibitory neurons promoting opposing actions” … and via homologues of the vertebrates’ neuropeptide Y.
Mapping the #Drosophila connectome made us all realize that the humble fly can do a lot more than we had been giving it credit for. Wouldn't surprise me if fruit flies can recognize each other. Many other insect species surely can recognize conspecifics.
Barry Condron did a playback video experiment with #Drosophila melanogaster larvae and claims that larvae can detect other larvae by visual input alone:
One of the best things about my current job is being able to collaborate in many different projects. This week a paper on the origins of movement in #drosophila came out! This is all the great work from Jonathan and Claudio, but it was great to support them with a bit of technical improvements to streamline their work! Read it all here at #openacess @ e-life (it was also great to have this under their new #preprint review system).
Stem cell microenvironment: Inter-niche signaling in #Drosophila ovary reveals a mechanism involving miR124 & EGFR that regulates #StemCell function & sharpens the spatial distinction between self-renewal & differentiation microenvironments #PLOSBiologyhttps://plos.io/3TM3Ajf
The Janelia #Unity Toolkit now supports panoramas, back-projected onto a cylindrical screen, updated in real time for a tracked viewpoint within the cylinder. The intended application is #VR for #Neuroscience studies of animals like #Drosophila. The code is a byproduct of another project so it's a bit experimental, but it's fun to watch examples like this one, meant to be displayed with three adjoining projectors. (1/2)
2 open postdoc positions for insect vision scientists at Mikko Juusola's lab in Sheffield, UK, in collaboration with Aurel Lazar at Columbia University:
"Elucidating the functional logic of 3D vision circuits of the #Drosophila brain"
The lab of Matthias Landgraf in Cambridge University has an opening for a Research Assistant/Research Associate to study critical periods of nervous system development using #Drosophila as a model.