||Fig. 3. Transcripts of α-neurexins are expressed in Xenopus oocytes.
Ovarian tissue consisting of connective tissue, follicle cells and oocytes
at different stages of development was subject to wholemount in situ
hybridisation using probes specific for each of the neurexin transcripts.
(A) An nrxn I specific probe identifies transcripts equally distributed
through small, early stage oocytes (yellow arrows). At later stages, the
nrxn Iα transcript is localised to a crescent within the large oocyte (red
arrows). Transcripts were not detected in cells other than oocytes. (B,C)
Nrxn II (B) and nrxn III (C) transcripts were found in all stages of oocyte.
At the later stages, in the large oocyte, the signal is less intense probably
due to the dilution of the mRNA in the larger cytoplasmic volume. There
was no evidence for localisation of these transcripts and neither were
they detected in cells other than oocytes. Right-hand-side panels: negative
controls, hybridised with corresponding sense neurexin cRNA probes