A cell-type atlas from a scyphozoan jellyfishAurelia coerulea(formerly sp.1) provides insights into changes of cell-type diversity in the transition from polyps to medusae

Abstract

AbstractWe provide here a detailed single cell transcriptomic atlas covering the life cycle of the cosmopolitan scyphozoanAurelia coerulea. We show that there is an increase in cell type diversity in the medusa stage, which is reflected by an increase in the number of unique transcripts expressed. We highlight parallels in both cell complement and specification pathways betweenAureliaand the sea anemoneNematostella, two lineages separated by more than 500 MY. We find that several cell types of the neuroglandular lineages are specified by the same transcription factors that arose by gene duplications in the common ancestor of medusozoans and anthozoans. This confirms gene duplications as a source for the increase of cellular complexity during the evolution of cnidarian neuroglandular lineages dates to the common ancestor of all cnidarians. We validated spatial expression domains corresponding to molecular profiles of smooth and striated muscles and followed the development of the striated muscle in the medusa. Our data suggests that striated muscles in the subumbrella of the medusa derive directly from smooth muscles, and yet these two muscle cell phenotypes are characterized by distinct molecular profiles. Further, reconstruction of putative cell trajectories indicates multipotent cell states derive from tissues at the boundary between epithelial layers and highlight molecular characteristics not typical of other cnidarians.TeaserSingle cell transcriptomic atlas across the jellyfish life cycle reveals increased cellular complexity associated with the medusa form.