Expression of CheSox11 (Group F) in the medusa, non-fertilised eggs and two-day planulae. (A) General view of a mature female medusa showing endodermal distribution of CheSox11 transcripts. (B) CheSox11 is expressed in a subpopulation of endodermal cells of the tentacular bulbs (limit between ectoderm and endoderm indicated by the dotted line). (C) Higher magnification view of the area boxed in A, showing CheSox11 expression in the endodermal circular canal (cc). (D) Endodermal cells of the radial canal (delineated by the white dotted line) which crosses the gonad also express CheSox11. Note that the gene is not expressed in the gonad itself (maturating oocytes, ov, are unstained). (E) CheSox11 expression in the manubrium endoderm (limit between ectoderm and endoderm indicated by the dotted line in the rectangle). (F) No expression was detected in unfertilised eggs (animal pole on the top, white star). (G) Endodermal staining in a two-day planula particularly concentrated in the anterior half. (H) Higher magnification view of the area boxed in G reveals the diffuse aspect of the staining. cc: circular canal, ect: ectoderm, end: endoderm, go: gonad, ma: manubrium, ov: maturing oocytes, tb: tentacle bulb. Scale bars: A, 50 μm; B, 20 μm; C, 10 μm; D to F, 50 μm, G, 50 μm; H, 10 μm.