Gaspar Jekely @jekely@qoto.org
- Platynereis connectome
- https://catmaid.jekelylab.ex.ac.uk
Professor at Centre for Organismal Studies (COS), University of Heidelberg, Germany
and
Living Systems Institute (LSI), University of Exeter, UK.
#neuroscience of marine larvae, #connectomics, #cilia, ciliary swimming, cell and nervous system #evolution, #GPCR, #neuropeptides, #Platynereis, #Trichoplax, #Nematostella, #Schistosoma, #coral #neuroscience #rstat #evolution
Joined Nov 2022
I am very happy to announce that our lab will soon move to the University of #Heidelberg to join the Centre for Organismal Studies (COS)
https://www.cos.uni-heidelberg.de/en
#COS
1/5
Great paper by Laura Piovani on high-quality cell atlases of oyster and polyclad flatworm larvae. Interesting new insights into cell-type diversity, young and old cell-types and evolution. Shell gland transcriptomes make oyster larvae look young. It was a pleasure to collaborate with Telford Lab et al. on this project. https://www.biorxiv.org/content/10.1101/2023.01.04.522730v1
In this paper we generated most of the figures entirely in R for open science and reproducibility. All code is shared here:
https://github.com/JekelyLab/Jasek_et_al
The figures and analyses can be regenerated by the code that will query our public #CATMAID database where all EM data, tracings and annotations are shared:
https://catmaid.jekelylab.ex.ac.uk (project id: 11)
#openscience #rstat
We also mapped #motoneuron synapses to the desmosomal connectome to infer the extent of tissue influenced by motoneurons. We suggest that such cellular-level maps based on #volumeEM data and the integrative analysis of synaptic and adherent force networks will be important to elucidate body mechanics and the nervous control of movement.
The #endoskeleton formed by the #aciculae and supported by many muscles is quite unique to polychaete annelids and represents the only example outside the #tetrapods of animals with a trunk appendages rigidified by an endoskeleton. Aciculae evolved in stem errant #annelids in the Early #Ordovician indicating the deep ancestry of these structures, predating tetrapod limbs.
We analysed the network in many different ways and found that its structure is quite different from the synaptic #connectome and random networks. One of the interesting findings was that the #aciculae - chitin rods that form an #endoskeleton in the segmental #appendages - are highly connected hubs in the #network and a large number of #muscles is involved in moving them.
Sanja skeletonised all the 853 muscle cells in the larva and annotated their desmosomes and the partner cells and extracellular structures that the desmosomes attach to. This resulted in a single network of over 2,000 cells and extracellular structures (basal lamina, chitin endoskeleton etc) that we call the desmosomal #connectome. In synaptic connectomes the links are formed by #synapses, in a desmosomal connectome the links are desmosomes.
The revised version of our paper on the desmosomal #connectome of the #Platynereis larva is now out
https://elifesciences.org/articles/71231
by Sanja Jasek et al.
#volumeEM #rstat
New #cryoET structure from LSI Exeter colleagues Matthew Gaines et al. Bertram Daum lab, this time of the enigmatic #archaeal filament called 'thread'.
What I find cool about this work is that first they had the structure, then found the sequence based on glycosylation sites and bulky residues.
This #protein was also so ultra-stable, that resisted trypsinisation, so mass spec was not an option to identify it.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9715654/
Our review with Stefan Gründer and Audrey Ortega Ramírez is out:
"Neuropeptides and DEG/ENaC ion channels: a relationship from mammals to cnidarians"
where we conclude based on structural comparisons and the #phylogeny of #neuropeptide systems that the interaction of DEG/ENaC channels with neuropeptides has diverse structural bases and many origins.
Finally, here is the Editor's evaluation from @elife
This paper reports on the development of an impressive microfluidic platform for the study of motility, and motility transitions, exhibited by single algal cells in circular confinement. Building on previous work that showed a three-state motility repertoire for certain green algae, the present work uses extremely long time series and a variety of physical perturbations to show how those dynamics can be altered by environmental conditions. The work will be of interest to a wide range of scientists studying motility and non-equilibrium dynamics.
https://doi.org/10.7554/eLife.76519.sa0
The authors also developed and tested a novel droplet-fusion assay to expose single cells in a controlled manner to chemicals. This could be a very elegant way to e.g., dissect #signalling mechanisms in the cells by #pharmacology.
The motility is light-switchable, which was known, but the long-term imaging of single cells in light and dark revealed a cellular #memory: the light-altered behavioural state persisted after light off.
The locomotion of single-cells is characterised by a trio of motility macrostates (run, stop, tumble) with distinct transition probabilities that could be quantified by long-term imaging.
#Chlamydomonas (2 #cilia) and #Pyramimonas (8 cilia) #algae were encapsulated into droplets by #microfluidics and imaged at high speed to characterise gait switching dynamics and the effect of light.
Great paper: a droplet #microfluidics assay to encapsulate single micron-sized algae to study long-term #behaviour.
https://elifesciences.org/articles/76519#fig4
by Bentley et al. gielenlab.com and @micromotility
A thread.
and the ciliary vane, which is very different from the mastigonemes of e..g. #Chlamydomonas
A cilium with wings.
Beautiful #cryoET paper on choanoflagellate #flagella #cilia revealing the enigmatic ciliary vane, new components and similarities to animal cilia
#protist #evolution #EM #choanoflagellate
https://elifesciences.org/articles/78133
- Platynereis connectome
- https://catmaid.jekelylab.ex.ac.uk
Professor at Centre for Organismal Studies (COS), University of Heidelberg, Germany
and
Living Systems Institute (LSI), University of Exeter, UK.
#neuroscience of marine larvae, #connectomics, #cilia, ciliary swimming, cell and nervous system #evolution, #GPCR, #neuropeptides, #Platynereis, #Trichoplax, #Nematostella, #Schistosoma, #coral #neuroscience #rstat #evolution
Joined Nov 2022
