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
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.
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.
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.
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.