Hammerschmidt et al., 1996 - Mutations affecting morphogenesis during gastrulation and tail formation in the zebrafish, Danio rerio. Development (Cambridge, England)   123:143-151

Fig. 1 Morphological characteristics of (A-F) one-eyed pinhead (oeptz257) and (G,H) dirty nose (dnste350) mutant embryos. In each section, wild type (+) is to the left, mutant to the right. (A) Tailbud stage, lateral view: the body axis is shorter; no pillow (indicated by an arrowhead) is formed at the anterior end of the hypoblast. (B,C) 8-somite stage: (B) lateral view, the head is reduced while the tailbud seems enlarged in oep mutants. (C) dorsal view of head region. (D) 24 hours, dorsal view of head region: the anterior part of the forebrain is missing while the eye vesicles are fused in oep mutants. (E) 24 hours, lateral view: the notochord is slightly undulated, the somites are slightly expanded along the a/p axis, the yolk tube is shorter and thicker, and the tail is curled down in oep mutants. (F) 24 hours, lateral view at level of yolk tube: no floorplate (arrow) can be detected in oep mutants. (G,H) dns, 24 hours, ventral view of head region: (G) brownish cells can be observed underneath the eyes (arrowhead); (H) acridine orange staining reveals apoptotic cells in the same region (arrowhead).

Fig. 2 Altered gene expression in mesoderm and neuroectoderm of oep and dns mutants revealed by in situ hybridization (A-C, E-K) and immunostaining (C,D). In each section, wild type (+) is to the left, mutants to the right. (A) gsc, 40% epiboly, animal view, dorsal right. (B) gsc, shield, animal view, dorsal right. (C) gsc mRNA in blue and Ntl protein (T) in brown, 70% epiboly, dorsal view. (D) fkd2, 10-somite stage, view on head: fkd2-positive presumptive hatching gland cells are absent in oep mutants. In dns mutants, very small fkd2-positive cells can be found at the anterior border of the hypoblast rather than in adjacent regions of the yolk sac. (E) fkd3, 70% epiboly, dorsal view: fkd3 expression is missing anterior to the diencephalic-mesencephalic boundary in oep mutants. (F) pax6, 3-somite stage, lateral view: the pax6 expression domain in the presumptive diencephalon reaches the anterior border of the CNS in oep mutants. (G) pax2, 12-somite stage, lateral view: pax2 expression is normal in the otic placode (asterisk) and in the midbrain (arrow) while the expression domain in the optic stalk (triangle) is missing. (H) dlx3, 12-somite stage, lateral view: the dlx3 expression is normal in the otic placode (asterisk) but absent in the olfactory placode (triangle) in oep mutants. (J) shh and pax2, tailbud-stage, view on head region: no shh expression can be detected in the brain anterior of the pax2-positive midbrain (asterisk). The axial transcripts posterior of the midbrain are located in the notochord. (K) shh, 22 hours, lateral view on tail region: shh expression is normal in the slightly undulated notochord but absent in the ventral cells of the spinal cord.

Fig. 3 Alterations in morphology in trilobite (tritk50) and spadetail (sptb104) mutants, compared to wild type (+). (A) 8-somite stage, dorsal view: both notochord and somites are shorter and wider in tri mutants. No somites are formed in spt mutants. (B) 30 hours, lateral view: tri embryos are shorter than wild-type and spt mutant embryos. Note the accumulation of cells at the tip of the tail in spt mutants.

Fig. 4 Altered gene expression in the mesoderm of spadetail (sptb104) and trilobite (tritk50) mutants compared to wild type (+), detected by in situ hybridization (A-E,G,H) and immunostaining (F). (A) sna1, 80% epiboly, dorsovegetal view. (B) ntl, 4-somite stage, dorsovegetal view. (C) myoD, 4-somite stage, dorsal view. (D) eve1, 4-somite stage, vegetal view. (E) sna1, 70% epiboly, dorsovegetal view. (F) ntl, 95% epiboly, dorsal view. (G) myoD, 10-somite stage, dorsal view on spread embryos, anterior on top. (H) eve1, 10-somite stage, vegetal view.

Fig. 5 Alterations in morphology and gene expression of pipetail (pptta98, A-J,L) and kugelig (kggtl240, C,K) mutant embryos, compared to wild type (+). (A) 10-somite stage, lateral view. (B) 10- somite stage, dorsal view: in ppt mutants, the notochord is undulated and the somites are condensed along the anteroposterior axis. Somites 9 and 10 and the presomitic mesoderm show a slight lateral expansion. (C) 24-somite stage, lateral view. (D) Day 5, ventral view of head: the head skeleton forms but fails to extend beyond the eyes, leading to a slight broadening of the head in ppt mutants. (E) Day 5, lateral view of tip of tail: the notochord and the neurocoel are slightly kinked at the end of the tail; the ventral gap of the melanophore stripe is present. (F-K) Dorsal view on spread embryo, anterior left: (F) wnt5, 5-somite stage: the expression of wnt5 is significantly reduced in somites and tailbud of ppt mutants. (G) wnt3, 5-somite stage. (H) ntl, 8-somite stage. (J) myoD, 12-somite stage: all somites are condensed, the posterior somites are laterally expanded in ppt mutants. (K) myoD, 16-somite stage: the posterior somites are condensed but not laterally expanded in kgg mutants. (L) eve1, 28- somite stage, lateral view on tail.

Unillustrated author statements

ZFIN wishes to thank the journal Development (Cambridge, England) for permission to reproduce figures from this article. Please note that this material may be protected by copyright.