Fig. 5 Shh signaling is required early for patterning the endocrine islet. Living fifth-generation homozygous INS-GFP or WT fixed embryos imaged at 48 hpf untreated (A, E) or treated with 50 μM cyclopamine at 6 (B, F), 8 (C, G), or 12 (D, H) hpf. Representative islet phenotypes are shown in living embryos as fluorescent (A–D) or as bright-field images after fixation and in situ hybridization with insulin probe (E–H). (A) 48-hpf untreated INS-GFP embryos. (B) Exposure to cyclopamine at 6 hpf. (C) Treatment at 8 hpf. (D) Cyclopamine exposure at 12 hpf. (E) Endogenous insulin expression in control ethanol-treated embryos. (F–H) Cyclopamine-treated embryos. Cyclopamine was added at 5 hpf (F); branchial arches (arrowhead), 8 (G) and 12 hpf (H). Abbreviations: s4, somite 4; s1, somite1; n, notochord; arrows, position of INS-GFP fluorescent cells; arrowheads, position of insulin-expressing cells.
Reprinted from Developmental Biology, 244(1), diIorio, P.J., Moss, J.B., Sbrogna, J.L., Karlstrom, R.O., and Moss, L.G., Sonic hedgehog is required early in pancreatic islet development, 75-84, Copyright (2002) with permission from Elsevier. Full text @ Dev. Biol.