|
Display additional annotations [+]
|
| |
Fig. 1. Immunostaining of stage 32 embryonic Xenopus brains for
expression of neuropilin-1 and NOC-2. A: Confocal microscope image of
a whole-mount brain immunostained for acetylated a-tubulin to reveal the
early scaffold of axon tracts. The principal longitudinal tract of the forebrain
is the tract of the postoptic commissure (TPOC) that merges with
the ventral longitudinal tract (VLT) of the midbrain. The ventral commissure
(VC) crosses the ventral midline and connects axons to the contralateral
TPOC. The rostral surface of the forebrain contains the anterior
commissure (AC) and the postoptic commissure (POC). Axons arising
from the nucleus of the presumptive telencephalon (nPT) give rise to the
supraoptic tract (SOT) that courses ventrally to merge with the TPOC.
Two ventrally directed axon tracts also merge with the TPOC: the dorsoventral
diencephalic tract (DVDT) and the tract of the posterior commissure
(TPC). B: Whole-mount Xenopus brain immunostained for neuropilin-
1. Neuropilin-1 is expressed on a subpopulation of axons within
the early scaffold of axon tracts. C: Double-label of B with the NOC-2
antibody. Double-labelled axons appear yellow. Neuropilin-1 and NOC-2
are coexpressed by a discrete subpopulation of forebrain axons.
D: Coronal section of the Xenopus forebrain at the level of the ventral
commissure double labelled for both neuropilin-1 and NOC-2. Commissurals
axons (arrows) that cross the ventral midline express both neuropilin-
1 and NOC-2. Scale bar 5 100 mm in A�C, 50 mm in D. |
