The HMG-box transcription factor XTcf-4 demarcates the forebrain-midbrain boundary.
A small subfamily of HMG-box transcription factors, the LEF/TCF group, serves as nuclear transducer of the Wnt-1/Wg signaling cascade. Upon Wnt-1/Wg signaling their members interact with beta-catenin and regulate the expression of Xenopus target genes siamois, twin, nodal related-3 or fibronectin. We have isolated a new HMG-box transcription factor in Xenopus that will be addressed XTcf-4 based on its homology to human and murine Tcf-4. Unlike XTcf-3, which is a maternal gene, and XLef-1 that is expressed after mid blastula transition (Molenaar et al., 1998. Mech. Dev. 75, 151-154), XTcf-4 expression starts at late neurula stage and is restricted to the anterior most midbrain demarcating the forebrain-midbrain boundary. The expression partially overlaps with a broad set of Xenopus Wnt family members in distinct patterns. XTcf-4 transcripts were also found partially co-localized with those of Xaxin, an intracellular antagonist of Wnt-1/Wg signaling.
König
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Department of Biochemistry, University of Ulm, Germany.
Gradl
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D
Kühl
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Wedlich
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D006609:High Mobility Group Proteins / Q000235:genetics*; D006801:Humans; D008636:Mesencephalon / Q000196:embryology*; D051379:Mice; D008969:Molecular Sequence Data; D016548:Prosencephalon / Q000196:embryology*; D017386:Sequence Homology, Amino Acid; D051820:TCF Transcription Factors; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors / Q000235:genetics*; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology*
D018076:DNA, Complementary; D006609:High Mobility Group Proteins; D051820:TCF Transcription Factors; C544894:TCF7L2 protein, human; C544895:Tcf7l2 protein, mouse; D058118:Transcription Factor 7-Like 2 Protein; D014157:Transcription Factors; D029867:Xenopus Proteins; C544896:tcf7l2 protein, Xenopus