Figure 1
Organization of a Botryllus schlosseri colony and blastogenic tissues.
(a) Part of a colony of B. schlosseri at stage B243 showing the emerging budlet (red frame) and neighboring non-budding tissues (green frame). (b) Example of microsurgery performed to harvest the budlet, before (up) and after (bottom) ablation of the budlet. The red square in the bottom left corner shows the isolated budlet alone. (c) Details of the tissues sampled for the RNAseq analyses: phalloidin and dapi staining (up) and sketches (bottom). From left to right: “Ref” (non-budding) sample, budlet stage A2 and budlet stage B2, respectively. Sampled tissues include a monolayered peribranchial epithelia (pbe), haemoblasts included in mesenchymal space (ms), a monolayered epidermis (e) and tunic (t) with embedded cells. In the samples at stage “A2” and “B2” the two epithelia (pbe and e) acquired budding capability and present the characteristic morphology, reviewed in Manni et al.10.
