Role of the Sc C terminus in transcriptional activation and E(spl) repressor recruitment.
Neurogenesis in all animals is triggered by the activity of a group of basic helix-loop-helix transcription factors, the proneural proteins, whose expression endows ectodermal regions with neural potential. The eventual commitment to a neural precursor fate involves the interplay of these proneural transcriptional activators with a number of other transcription factors that fine tune transcriptional responses at target genes. Most prominent among the factors antagonizing proneural protein activity are the HES basic helix-loop-helix proteins. We have previously shown that two HES proteins of Drosophila, E(spl)mgamma and E(spl)m7, interact with the proneural protein Sc and thereby get recruited onto Sc target genes to repress transcription. Using in vivo and in vitro assays we have now discovered an important dual role for the Sc C-terminal domain. On one hand it acts as a transcription activation domain, and on the other it is used to recruit E(spl) proteins. In vivo, the Sc C-terminal domain is required for E(spl) recruitment in an enhancer context-dependent fashion, suggesting that in some enhancers alternative interaction surfaces can be used to recruit E(spl) proteins.
Giagtzoglou
Nikolaos
N
Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Hellas, Vasilika Vouton, Heraklion, GR 71110, Greece.
Koumbanakis
Konstantinos A
KA
Fullard
John
J
Zarifi
Ioanna
I
Delidakis
Christos
C
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D051792:Basic Helix-Loop-Helix Proteins; D001665:Binding Sites; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D019281:Dimerization; D029721:Drosophila Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics*; D004742:Enhancer Elements, Genetic / Q000235:genetics; D017344:Genes, Insect / Q000235:genetics*; D018257:Helix-Loop-Helix Motifs; D008969:Molecular Sequence Data; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism*; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C121960:E(spl)m7-HLH protein, Drosophila; C091023:gro protein, Drosophila; C089197:sc protein, Drosophila