Fig. 7

Expression analysis of a selection of genes representatives of clusters 6, 7 and 11 during Platynereis’ posterior regeneration. Whole-mount in situ hybridizations (WMISH) for the genes whose name is indicated are shown for all regeneration stages (0 dpa to 5 dpa) as well as 15 dpa as a proxy of non-amputated control. All panels are ventral views (anterior is up). Outlines of the regenerated structures are depicted in black for the most transparent samples. A WMISH for Pdu-collier. Blue arrow heads:  differentiated neurons of the ventral nerve chord (VNC); red arrow heads: neurons present inside the blastema; black arrow heads: neurons inside the reformed VNC. B WMISH for Pdu-bra. Blue arrow heads: wound epithelium. Red arrow heads: small blastema. White asterisks: anus. Black arrow heads: reforming/reformed pygidium. C WMISH for Pdu-otp. Blue arrow heads: VNC of non-amputated segments. Black arrow heads: VNC of regenerated structures. Black arrows: peripheral structures. Red arrow heads: basis of the anal cirri. D WMISH for Pdu-slit. Blue arrow heads: enteric nerve net. Red arrow heads: Mass of cells expressing slit at early stages of regeneration. White asterisk: midline. Black arrow heads: ectodermal stripes. E WMISH for Pdu-netrin. Blue arrow heads: scattered cells inside the midline of non-amputated segments. Red arrow heads: midline of regenerating structures. Red arrows: midline-contiguous mediolateral domains expressing netrin. F WMISH for Pdu-pax6.  Blue arrow heads: longitudinal ventro-lateral lines of cells. G WMISH for Pdu-egr. Blue arrow heads: mass of ventral abutting the amputation plane. Red arrow heads: wound epithelium. Red arrows: strong expression of egr in the segment abutting the amputation plane. Black arrow heads: scattered egr-expressing cells, potentially neurons. Black asterisk: VNC