Ectopic wound-induced notum is correlated with the formation of an ectopic anterior pole in a Wnt-high environment.

(A) FISH shows split anterior poles ( notum/ foxD+ ) in 72 hours regenerating activin-2 RNAi animals. (B) FISH show anterior ( notum ) and posterior ( wnt1 ) pole markers at 12 days post amputation in activin-2 RNAi animals. (C) FISH shows expression of notum and wnt1 in the same posterior-facing wound of an a ctivin-2 RNAi regenerating fragment at 30 hours post amputation. Green arrows show notum+ cells. White arrows denote cells that co-express notum and wnt1 . (D) FISH shows regenerating fragments resetting PCG ( ndl-5 , notum , wntP-2) expression and nucleating new anterior poles at different time points. activin-2 RNAi animals show ectopic anterior poles at posterior-facing wounds. Boxes indicate high magnification images shown below. (E) FISH shows anterior pole markers ( notum and foxD ), and the posterior pole marker ( wnt1 ) at the same posterior-facing wound of a regenerating fragment at 36 hours of regeneration. Zoom out seen in S7A Fig . (F) FISH shows posterior-facing wound of regenerating fragments at five days. Posterior related ( wntP-2) and anterior related ( notum/sFRP-1 +) gene expression by FISH. (G) FISH shows ovo+ eye progenitors and expression of anterior ( sFRP-1) and posterior ( wntP-2) PCGs at posterior-facing wounds of an activin-2 RNAi animal. Boxes: zoom ins on the right. Magenta, anterior-facing wound; green, posterior-facing wound. Scale bars, 200 μm, except for high magnification panels in where they represent 10 μm.