Desmosomal connectomics of all somatic muscles in an annelid larva
Abstract
Cells form networks in animal tissues through synaptic, chemical and adhesive links. Invertebrate muscle cells often connect to other cells through desmosomes, adhesive junctions anchored by intermediate filaments. To study desmosomal networks, we skeletonised 853 muscle cells and their desmosomal partners in volume electron microscopy data covering an entire larva of the annelid Platynereis. Muscle cells adhere to each other, to epithelial, glial, ciliated, and bristle-producing cells and to the basal lamina, forming a desmosomal connectome of over 2,000 cells. The aciculae - chitin rods that form an endoskeleton in the segmental appendages - are highly connected hubs in this network. This agrees with the many degrees of freedom of their movement, as revealed by video microscopy. Mapping motoneuron synapses to the desmosomal connectome allowed us to infer the extent of tissue influenced by motoneurons. Our work shows how cellular-level maps of synaptic and adherent force networks can elucidate body mechanics.
Data availability
All EM, tracing and annotation data are available at https://catmaid.jekelylab.ex.ac.ukAll code is available at https://github.com/JekelyLab/Jasek_et_al
Article and author information
Author details
Funding
European Commission (FP7-PEOPLE-2012-ITN grant no. 317172)
- Sanja Jasek
- Gáspár Jékely
Wellcome Trust (Investigator Award 214337/Z/18/Z)
- Sanja Jasek
- Csaba Verasztó
- Réza Shahidi
- Gáspár Jékely
European Research Council (grant agreement No 101020792)
- Alexandra Kerbl
- Gáspár Jékely
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Jasek et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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