| |
FIG. 1. A-E: In situ distribution of XHR transcripts during gastrula and early neurula stages. A: Lateral view of a mid-gastrula stage
embryo. Arrowheads mark the anterior–posterior extension of XHR-negative cells in dorsal ectoderm. Arrows enclose ventral marginal
zone. B: dorsal view of a late gastrula. C: anterior view of the same embryo as shown in B. Arrowheads point out a stripe of strong XHR
expression at the anteriormost border of the presumptive neural plate. D: anterior view of an embryo at stage 15. Arrowheads mark the
anterior and lateral border of the neural plate, also labelled by cells with strong XHR expression. E: dorsal view of the same embryo as
shown in D. Arrowheads point out the posterior border of the stripe of cells with strong XHR expression. F-G: Localization of XHL transcripts
during gastrulation and early neurulation. F: dorso-vegetal view of a mid-gastrula stage embryo. G: dorsal view of a stage 13 embryo stained
for XHL mRNA. The dorsal border of XHR expression is marked by arrowheads. H: Cross-sections of a late gastrula embryo prior subjected
to whole-mount in situ hybridization. Arrows mark the dorsal border of XHR expression in ectoderm. I: Cross-section of an early neurula
at the level of the eye anlage. Arrows point out the dorsal expression border of XHR in the epithelial layer of the neuroectoderm. Arrowheads
mark the lateral border of XHR-positiv cells in the sensorial layer of the neuroectoderm. J: Close-up of a cross-section through an embryo
at stage 15 at the level of the prospective trunk region. Arrow points out the dorsal border of XHR expression in the epithelial layer of
neuroectoderm. Bracket encloses XHR-expressing cells in the sensorial layer of the neural plate. Arrowhead marks the border between
neural plate and epidermis. K: sagittal section of a neurula embryo. Arrows point out the anterior and posterior border of XHR expression.
Arrowhead marks the anterior border of the neural plate. adm: anterior dorsal mesoderm; ae: archenteron; am: axial mesoderm; ant:
anterior; bl: blastocoel; bp: blastopore; dors: dorsal; el: epithelial layer of ne; epi: epidermis; n: notochord; ne: neuroectoderm; np: neural
plate; sl: sensorial layer of ne; sm: somitic mesoderm; post: posterior; vent: ventral; yp: yolk plug. |
