XB-IMG-136087
Xenbase Image ID: 136087
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Figure 4. Persistence and differentiation of the enlarged CNS
after ASH3b RNA injection. (A-D) N-CAM mRNA detected in
swimming tadpoles (stage 45) by whole-mount in situ hybridization;
staining is purple. Some brown pigmentation is present
in the pigment epithelium of the eye, but these animals are
otherwise albino. (A) A wild-type animal. (B-D) A tadpole arising
from an injected embryo (inj: injected side). On the uninjected
control side {B), the eye (e) is normally positioned within
the mostly neural crest-derived eye socket, and the gill arches
(g) and vagus complex (v) are normal sized. However, on the
injected side {D), the eye is adjacent to the brain because of the
reduced eye socket, the vagus complex is smaller, and the gill
arches are absent (large open arrow). A dorsal view (C) shows the
massive enlargement of the brain and anterior spinal cord on the
injected side. Small open arrows in B and D indicate the olfactory
organs. The olfactory organ on the injected side is enlarged.
(E) Dorsal view of a tadpole (stage 45) stained for the 2G9 neural
epitope (purple). The 2G9 epitope stains differentiated neurons.
The brain and anterior spinal cord are expanded laterally on the
injected side (black line shows midline), but the anterior-posterior
patterning of the brain, revealed by staining intensity
variations, appears normal. Some lateral line organs (o) are disorganized
or missing on the affected side, whereas the gill
arches are smaller (open arrow). The eye is also positioned closer
to the brain on the injected side, reflecting a slightly reduced eye
socket. (F) A dorsal view of tailbud embryos (stage 31) stained
with an antibody to NF-M. The lower embryo is an uninjected
control; the upper embryo was injected with ASH3b RNA on
the marked side. At this age, NF-M is present in early differentiated
neurons (primary neurons) and their processes. On the
affected side of the upper embryo, the more anterior NF-Mexpressing
cells in the hindbrain are disorganized (arrow),
whereas NF-M-expressing cells are almost absent from the spinal
cord (posterior to arrow). The embryos in F are cleared. Anterior
is to the left in A-C, E, and F and to the right in D. Image published in: Turner DL and Weintraub H (1994) Copyright © 1994. Image reproduced on with permission of the Publisher, Cold Spring Harbor Laboratory Press. This is an Open Access article. Larger Image Printer Friendly View |