XB-ART-21122
Mech Dev
July 1, 1994;
47
(1):
19-28.
Cloning and developmental expression of LFB3/HNF1 beta transcription factor in Xenopus laevis.
Demartis A
,
Maffei M
,
Vignali R
,
Barsacchi G
,
De Simone V
.
Abstract
We have cloned the Xenopus laevis homologue of the
LFB3/
HNF1 beta transcription factor. RNase protection and in situ hybridisation experiments show that XLFB3 transcription starts in the gastrulating
endoderm at
stage 10.5 (mid-
gastrula). At later stages, XLFB3 transcripts within the
endoderm are restricted to mid- and
hindgut and to their derivative organs and tissues. XLFB3 is also expressed in the
neuroectoderm and in the
pronephros anlage. XLFB3 is not expressed in the rostral part of all three germ layers, with coincident
anterior borders that are shifted anteriorly by treatment of developing embryos with retinoic acid. XLFB3 is a useful marker of early
endoderm differentiation and its expression pattern along the antero-
posterior axis, as well as the response to retinoic acid treatment, suggests a role in early morphogenesis.
PubMed ID:
7524626
Article link:
Mech Dev
Species referenced:
Xenopus laevis
Genes referenced:
hnf1a
hnf1b
Article Images:
[+] show captions
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Fig. 4 (a) In situ hybridisation showing XLFB3 mRNA distribution
on a saginal section of a st. 10.5 embryo of X. laevis. Positive signal
is detectable only in the invaginated endoderm. (b and c) In situ
hybridisation of sagittal sections of a st. 12 and a st. 18 X. laevis em-
bryos, respectively. Neuroectoderm and endoderm are labelled, except
for the most anterior part. A strong signal is present on the hepatic
diverticle, i.e. = invaginated endoderm; imz = involuting marginal
zone; bl = blastopore; ym = yolk mass; ne = neuroectoderm; ar = ar-
chenteron roof; eym = endodermal yolk mass; ba = brain anlage;
Id = liver diverticulum.
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Fig. 5. Bright (a) and dark (b) fields of a transversal section of a st.
16 X. laevis embryo. Labelling is visible on the neuroectoderm, inter-
mediate mesoderm and endoderm, im = intermediate mesoderm;
np= neural plate; ar = archenteron roof; eym -- endodermal yolk
mass,
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Fig. 6 (a) In situ hybridisation showing XLFB3 mRNA distribution on a transversal section of a st. 23 X. laevis embryo. A strong positive signal
is present in the two pronephric regions and in the endoderm. A signal is also present in the roof plate of the neural tube. (b and c) Parasagittal
and sagittal sections, respectively, of st. 23 embryos. (d and e) Two parasagittal sections (at different levels) of st. 29-30 embryos, rp = roof plate;
p = pronephros; eym = endodermal yolk mass; wd = Wolffian duct.
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Fig. 7. Bright (a) and dark (b) fields of a saginal section of a st. 48 X.
laevis embryo. Positive signal is present in developing mesonephric
vesicles and in several tissues derived by the digestive tract, me =
mesonephric vesicles; s = stomach; i = intestine; li = liver;
p = pancreas; wd = Wolffian duct.
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