|
|
|
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 5. Zic2-induced turning of ipsilateral retinal axons away from the midline
is mediated by both EphB1-dependent and -independent pathways. (A)
Quantitative RT-PCR for EphB1 performed on non-electroporated or
electroporated mouse retinas at E13.5 with CAG-EGFP or with CAG-Zic2/CAG-EGFP
plasmids. EphB1 levels significantly increase after ectopic
expression of Zic2 in the center of the retina by in utero electroporation, as
compared with control retinas. More than ten retinas for each condition were
pooled per experiment. Data from seven different experiments are shown. Error
bars indicate s.e.m.; *P<0.005. (B) Left panels
show axonal trajectories of targeted RGCs at the optic chiasm. Middle panels
show the location of the targeted RGCs (green) in retinal whole-mounts (gray).
Right panels are cartoons summarizing the results in each particular case.
(a) In wild-type embryos electroporated at E13.5 with Zic2/EGFP, many
of the green axons originating from the central retina turn at the midline.
(b) In EphB1-/- embryos ectopically expressing only
EGFP in the central retina, no ipsilateral axons are seen at the chiasm.
(c) When Zic2/EGFP are ectopically expressed in the central retina of
EphB1-null embryos at E13.5, the number of axons projecting
ipsilaterally does not change as dramatically as when wild-type embryos are
electroporated with Zic2/EGFP, but a significant proportion of axons that
project ipsilaterally can be still detected. White arrows indicate ipsilateral
projections. ON, optic nerve; cOT, contralateral optic tract; iOT, ipsilateral
optic tract; d, dorsal; n, nasal; t, temporal; v, ventral. Scale bars: chiasm
panels, 200 µm; retina panels, 500 µm.
|
