Osa associates with the Brahma chromatin remodeling complex and promotes the activation of some target genes.
The yeast SWI/SNF complex and its Drosophila and mammalian homologs are thought to control gene expression by altering chromatin structure, but the mechanism and specificity of this process are not fully understood. The Drosophila osa gene, like yeast SWI1, encodes an AT-rich interaction (ARID) domain protein. We present genetic and biochemical evidence that Osa is a component of the Brahma complex, the Drosophila homolog of SWI/SNF. The ARID domain of Osa binds DNA without sequence specificity in vitro, but it is sufficient to direct transcriptional regulatory domains to specific target genes in vivo. Endogenous Osa appears to promote the activation of some of these genes. We show evidence that some Brahma-containing complexes do not contain Osa and that Osa is not required to localize Brahma to chromatin. These data suggest that Osa modulates the function of the Brahma complex.
Collins
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RT
Skirball Institute for Biomolecular Medicine, Department of Cell Biology, New York University School of Medicine, 540/550 First Avenue, New York, NY 10016, USA.
Furukawa
T
T
Tanese
N
N
Treisman
J E
JE
D000818:Animals; D030801:Animals, Genetically Modified; D020029:Base Pairing; D001665:Binding Sites; D018797:Cell Cycle Proteins; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D002843:Chromatin / Q000502:physiology* / Q000648:ultrastructure; D002874:Chromosome Mapping; D002875:Chromosomes / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster; D005786:Gene Expression Regulation; D017344:Genes, Insect; D006257:Head; D012045:Regulatory Sequences, Nucleic Acid; D012469:Salivary Glands / Q000502:physiology / Q000648:ultrastructure; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014921:Wings, Animal
D018797:Cell Cycle Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D015534:Trans-Activators; C086469:brm protein, Drosophila; C117995:osa protein, Drosophila