Armadillo coactivates transcription driven by the product of the Drosophila segment polarity gene dTCF.
The vertebrate transcription factors TCF (T cell factor) and LEF (lymphocyte enhancer binding factor) interact with beta-catenin and are hypothesized to mediate Wingless/Wnt signaling. We have cloned a maternally expressed Drosophila TCF family member, dTCF. dTCF binds a canonical TCF DNA motif and interacts with the beta-catenin homolog Armadillo. Previous studies have identified two regions in Armadillo required for Wingless signaling. One of these interacts with dTCF, while the other constitutes a transactivation domain. Mutations in dTCF and expression of a dominant-negative dTCF transgene cause a segment polarity phenotype and affect expression of the Wingless target genes engrailed and Ultrabithorax. Epistasis analysis positions dTCF downstream of armadillo. The Armadillo-dTCF complex mediates Wingless signaling as a bipartite transcription factor.
van de Wetering
M
M
Department of Immunology, University Hospital, Utrecht, The Netherlands.
Cavallo
R
R
Dooijes
D
D
van Beest
M
M
van Es
J
J
Loureiro
J
J
Ypma
A
A
Hursh
D
D
Jones
T
T
Bejsovec
A
A
Peifer
M
M
Mortin
M
M
Clevers
H
H
D000595:Amino Acid Sequence; D000818:Animals; D051186:Armadillo Domain Proteins; D019521:Body Patterning / Q000235:genetics; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D017344:Genes, Insect; D006609:High Mobility Group Proteins / Q000235:genetics* / Q000378:metabolism; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D051821:Lymphoid Enhancer-Binding Factor 1; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000502:physiology; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000502:physiology; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology*; D051155:Wnt1 Protein
C495305:ARM protein, Drosophila; D051186:Armadillo Domain Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006609:High Mobility Group Proteins; D019476:Insect Proteins; D051821:Lymphoid Enhancer-Binding Factor 1; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051155:Wnt1 Protein; C115159:pan protein, Drosophila; C074622:wg protein, Drosophila