The interaction between the coactivator dCBP and Modulo, a chromatin-associated factor, affects segmentation and melanotic tumor formation in Drosophila.
The development of Drosophila requires the function of the CREB-binding protein, dCBP. In flies, dCBP serves as a coactivator for the transcription factors Cubitus interruptus, Dorsal, and Mad, and as a cosuppressor of Drosophila T cell factor. Current models propose that CBP, through its intrinsic and associated histone acetyltransferase activities, affects transient chromatin changes that allow the preinitiation complex to access the promoter. In this report, we provide evidence that dCBP may regulate the formation of chromatin states through interactions with the modulo (mod) gene product, a protein that is thought to be involved in chromatin packaging. We demonstrate that dCBP and Modulo bind in vitro and in vivo, that mutations in mod enhance the embryonic phenotype of a dCBP mutation, and that dCBP mutations enhance the melanotic tumor phenotype characteristic of mod homozygous mutants. These results imply that, in addition to its histone acetyltransferase activity, dCBP may affect higher-order chromatin structure.
Bantignies
Frédéric
F
Vollum Institute and Department of Cell and Developmental Biology L-215, Oregon Health Sciences University, Portland, OR 97201, USA.
Goodman
Richard H
RH
Smolik
Sarah M
SM
D000123:Acetyltransferases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D050882:CREB-Binding Protein; D002843:Chromatin / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*
D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; C117962:mod protein, Drosophila; D000123:Acetyltransferases; D050882:CREB-Binding Protein