The Drosophila gene brinker reveals a novel mechanism of Dpp target gene regulation.
decapentaplegic (dpp), a Drosophila member of the TGFbeta family of secreted molecules, functions as a long-range morphogen in patterning of the embryo and the adult appendages. Dpp signals via the SMAD proteins Mad and Medea. Here we show that in the absence of brinker (brk), Mad is not required for the activation of Dpp target genes that depend on low levels of Dpp. brk encodes a novel protein with features of a transcriptional repressor. brk itself is negatively regulated by Dpp. Dpp signaling might relieve brk's repression of low-level target genes either by transcriptional repression of brk or by antagonizing a repressor function of brk at the target gene promoters.
Max-Planck-Institut für Entwicklungsbiologie, Tübingen, Germany.
A
A
Jaźwińska
N
N
Kirov
E
E
Wieschaus
S
S
Roth
C
C
Rushlow
D000818:Animals; D052005:Bone Morphogenetic Protein Receptors, Type I; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics; D019476:Insect Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics; D010641:Phenotype; D011401:Promoter Regions, Genetic / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000235:genetics; D017978:Receptors, Growth Factor / Q000235:genetics*; D012097:Repressor Proteins; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000502:physiology; D051905:Smad6 Protein; D020825:T-Box Domain Proteins; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D014921:Wings, Animal / Q000254:growth & development
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D019476:Insect Proteins; C112506:MAD protein, Drosophila; D009419:Nerve Tissue Proteins; D011956:Receptors, Cell Surface; D017978:Receptors, Growth Factor; D012097:Repressor Proteins; D051905:Smad6 Protein; D020825:T-Box Domain Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C064196:dpp protein, Drosophila; C085793:salm protein, Drosophila; C072962:bi protein, Drosophila; C090169:tkv protein, Drosophila; D017346:Protein Serine-Threonine Kinases; D052005:Bone Morphogenetic Protein Receptors, Type I