Sato Y, Narasaki I, Kunimoto T, Moriyama Y, Hashimoto C.

	Fig. 2 ACE embryo lacking blastocoel roof and ventral two-thirds of the marginal zone developed the complete dorsal structures. a Schematic drawing of removal of the blastocoel roof and the ventral marginal zone at ACE. b The ACE embryo after removal of the blastocoel roof and ventral marginal zone. c The percentage of the embryo with dorsal structure after the removal of the indicated amount of the vegetal marginal zone at ACE. d, e The tailbud embryos developed from control and operated ACE embryo. Scale bars, 1 mm. f–y In situ hybridization of control and operated embryos. Scale bars, 500 µm. The expression of bf1 (f, g), otx2 (h, i), rx2a (j, k), pax6 (l, m), krox20 (n, o), hairy2 (p, q), gsc (r, s), and chd (t, u) in the neurula stage. The expression of myoD (v, w) and bra (x, y) in the tailbud stage
	Fig. 3 ACE embryo lacking yolky endoderm developed the complete dorsal structures. a Schematic drawing of the yolky endoderm removal at ACE. b, c The tailbud embryos developed from control and operated ACE embryo. Scale bars, 1 mm. d–w In situ hybridization of control and operated embryos. Scale bars, 500 µm. The expression of bf1 (d, e), otx2 (f, g), rx2a (h, i), pax6 (j, k), krox20 (l, m), hairy2 (n, o), gsc (p, q), and chd (r, s) in the neurula stage. The expression of myoD (t, u) and bra (v, w) in the tailbud stage
	Fig. 4 Transplantation of mGFP-labeled dorsal marginal zone at ACE into the ventral side of non-labeled ACE embryo. a Schematic drawing of the transplantation assay. b The whole-mount view of operated embryo at the tailbud stage. White arrowheads, mGFP-labeled secondary body axis. c The transverse section of head in the secondary body axis. White arrowhead, neural tube. Black arrowheads, eyes. d The transverse section of trunk region in the secondary body axis. White arrowhead, neural tube. Black arrowhead, notochord
	Fig. 5 The explant of blastocoel roof of blastula developed an embryo only lacking yolk mass. a Schematic drawing of the blastocoel roof explant of blastula. b, c The tailbud embryos developed from control and operated blastocoel roof explant of blastula. Scale bars, 1 mm
	Supplementary Fig. 1 Transplantation of non-labeled dorsal marginal zone at ACE into the ventral side of mGFP-labeled ACE embryo. (a) Schematic drawing of the transplantation assay. (b) The lateral view of the operated embryo at tailbud stage. The non-labeled secondary body axis was formed at the ventral side. (c) The ventral view of the operated embryo. The head and the tail of the secondary body axis were completely non-labeled.
	Supplementary Fig. 2 The explant of dorsal marginal zone at ACE developed into an embryoid possessing a complete dorsal structure (a) Schematic drawing of dorsal marginal zone explant at ACE. (b) The explant of dorsal marginal zone at ACE. (c, d) The tailbud embryos developed from control and operated explant. Scale bars, 1 mm. (e-x) in situ hybridization of control and operated explant. Scale bars, 500 μm. The expression of bf1 (e, f), otx2 (g, h), rx2a (i, j), pax6 (k, l), krox20 (m, n), hairy2 (o, p), gsc (q, r), chd (s, t) in neurula stage. The expression of myoD (u, v), bra (w, x) in tailbud stage.

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