YY1 binds five cis-elements and trans-activates the myeloid cell-restricted gp91(phox) promoter.
Four transcriptional activating cis-elements within the gp91(phox) promoter bind a protein complex of similar mobility and binding specificity, denoted BID (binding increased during differentiation). The intensity of BID complexes increases upon myeloid cell differentiation, coincident with induction of gp91(phox) expression, and BID competes with the transcriptional repressor CDP for binding to each of these promoter elements. To determine the identity of BID, an expression library was ligand screened with the BID-binding site that surrounds the -145-base pair (bp) region of the gp91(phox) promoter. One recovered factor that exhibits the expected binding specificity is YY1, a ubiquitous multifunctional transcription factor. BID complexes that form with the four binding sites within the gp91(phox) promoter are disrupted by YY1 antiserum, and a fifth YY1-binding site was detected in the -412-bp promoter region. Overexpression of YY1 in transient co-transfection assays trans-activates a minimal promoter containing two copies of the -145-bp binding site from the gp91(phox) promoter. Neither the level of YY1 protein nor DNA binding activity increases during myeloid cell differentiation. These studies identify a target gene of YY1 function in mature myeloid cells, and demonstrate that YY1 function can be controlled during myeloid development by the modulation of a competing DNA-binding factor.
Jacobsen
B M
BM
Herman B Wells Center for Pediatric Research, Section of Pediatric Hematology/Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
Skalnik
D G
DG
D001483:Base Sequence; D002454:Cell Differentiation; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D006367:HeLa Cells; D006801:Humans; D020014:K562 Cells; D008562:Membrane Glycoproteins / Q000235:genetics*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation; D050986:YY1 Transcription Factor
D017931:DNA Primers; D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D008562:Membrane Glycoproteins; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; D004247:DNA; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases