|
Fig. 7. Xenopus basic transcription
element binding protein
(xBTEB) mRNA expression is induced
by 3,5,3 -triiodothyronine
(T3) in premetamorphic tadpole
brain. Nieuwkoop and Faber stage
52 tadpoles were treated with or
without 50 nM T3 for 48 h before
they were killed. Saggital sections
(10 μm) were hybridized with antisense
digoxigenin-labeled cDNA
probes for xBTEB (optic tectum,
xBTEB mRNA is green in panels A
and B [bar, 100 μm]; lateral motor
column, xBTEB mRNA is red in
panels C and D [bar, 50 μm]);
hybridization with sense probe
showed no staining (data not
shown). xBTEB mRNA and thyroid
hormone receptor (TR) protein are
expressed in the same cells. Dual
histochemistry for xBTEB mRNA
(red) and TR protein (green; analyzed
by immunohistochemistry)
was conducted (the lateral motor
column is shown in panels C and
D). Note the low level of xBTEB
mRNA expression (cytoplasmic
red staining) and the absence of
detectable TR protein (lack of
nuclear staining) at this developmental
stage. Hormone treatment
was as described above (C,
untreated; D, 50 nM T3). |