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Fig. 8
Aberrant somitogenesis in Neogenin morphants. (a-b) Sagittal sections through the trunk of 24 hpf embryos stained with hematoxylin and eosin. (a) Within the somites of control embryos, cells lined up to form discrete V-shaped epithelial boundaries (arrows) surrounding more loosely packed mesenchymal cells in the interior. (b) In the morphants, U-shaped epithelial boundaries (arrows) were formed and boundary cells remained rounded and loosely packed. Fewer mesenchymal cells were present within the interior of each somite. (c) At 14 hpf (10 somites), myoD expression was present in the caudal half of each somite (so) and the adaxial cells situated adjacent to the notochord (nc) in control embryos. (d) Morphant embryos exhibited the expected myoD expression pattern; however, the width of myoD expression in each somite was markedly reduced in the rostrocaudal direction and expanded in the mediolateral direction. (a and b) Rostral to the left, dorsal to the top. (c and d) Dorsal views with rostral to the top.
Reprinted from Developmental Biology, 269(1), Mawdsley, D.J., Cooper, H.M., Hogan, B.M., Cody, S.H., Lieschke, G.J., and Heath, J.K., The Netrin receptor Neogenin is required for neural tube formation and somitogenesis in zebrafish, 302-315, Copyright (2004) with permission from Elsevier. Full text @ Dev. Biol.