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Display additional annotations [+]
Gene |
Clone |
Species |
Stages |
Anatomy |
neurog2
|
|
laevis
|
NF stage 15
|
chordal neural plate
,
olfactory region
,
posterior placodal area
,
anterior neural ridge
|
neurog2
|
|
laevis
|
NF stage 20
|
olfactory placode
,
olfactory region
,
presumptive midbrain-hindbrain boundary
,
posterior placodal area
,
anterior neural ridge
|
ebf3
|
|
laevis
|
NF stage 20
|
olfactory placode
,
posterior neural tube
,
olfactory region
,
neural tube
,
presumptive midbrain-hindbrain boundary
,
[+]
|
neurod4
|
|
laevis
|
NF stage 17
|
olfactory region
,
chordal neural plate border
,
posterior placodal area
,
anterior neural ridge
|
neurod4
|
|
laevis
|
NF stage 20
|
olfactory placode
,
posterior placodal area
,
anterior neural ridge
|
atoh7
|
|
laevis
|
NF stage 18
|
olfactory region
,
anterior neural ridge
|
atoh7
|
|
laevis
|
NF stage 20
|
olfactory placode
,
anterior neural ridge
|
|
|
Fig. 1. sequential activation of basic helix-loop-helix (bHLH) and repeat HLH (rHLH) transcription factors during early olfactory development. A: X- NgnR-1 was expressed at stage (St) 15 in the region of the lateral anterior neural ridge, which is fated to produce the olfactory placodes. B: This expression was maintained as the placode develops, shown at stage 20. C: The rHLH gene Xebf2 was first detected at stage 16 within this same region. D: Xebf2 expression also persisted within the olfactory placode in the same domain as that of X-NgnR-1, shown at stage 20. The two Xenopus atonal homologues Xath3 and Xath5 were expressed beginning at stage 17, with Xath5 staining readily apparent at stage 18 (E and G, respectively). F,H: Their expression persisted within the presumptive olfactory region and was still present at stage 20. I: Xebf3 was not expressed in the nascent olfactory region until stage 20, concomitant with the earliest N-tubulin expression within the developing olfactory placodes (data not shown). All embryos are shown in an anterior view, dorsal toward the top; arrows indicate olfactory expression. |