Expression of two myeloid cell-specific genes requires the novel transcription factor, c-fes expression factor.
The protein product of the c-fes proto-oncogene has been implicated in the normal development of myeloid cells (macrophages and granulocytes). We have previously shown that 151 base pairs of c-fes 5'-flanking sequences are sufficient for myeloid cell-specific expression and include functional binding sites for Sp1, PU.1, and a novel nuclear factor (Heydemann, A., Juang, G., Hennessy, K., Parmacek, M. S., and Simon, M. C. (1996) Mol. Cell. Biol. 16, 1676-1686). This novel hematopoietic transcription factor, termed FEF (c-fes expression factor), binds to a cis-acting element that is located at nucleotides -9 to -4 of the c-fes promoter between two Ets binding sites (at -19 to -15 and -4 to +1) which bind PU.1. We now show that a FEF binding site exists in the myeloid cell-specific regulatory region of a second gene, the -2.7-kilobase pair enhancer of chicken lysozyme. The lysozyme FEF site is immediately 5' to a PU. 1 site, analogous to their arrangement in the c-fes promoter, and allows the formation of a preliminary FEF consensus site, 5'-GAAT(C/G)A-3'. This consensus site does not match any sites for known transcription factors. Importantly, although PU.1 binds immediately 3' of the FEF site in both the c-fes promoter and the chicken lysozyme enhancer (CLE), we show that they bind independently. The FEF sites are required for high levels of transcription by both the CLE and the c-fes promoter in transient transfection experiments. Importantly, elimination of the CLE FEF site abolishes all transcriptional activity of this enhancer element. Mutation of the adjacent PU.1 site in either the c-fes promoter or the CLE, reduces activity by approximately 50%. Therefore, transcription of both lysozyme and fes in myeloid cells requires FEF and PU.1. UV cross-linking experiments show that the FEF binding activity consists of a single 70-kDa protein in both human and murine cell lines. FEF binding activity is not affected by antibodies that specifically recognize a number of cloned transcription factors. Collectively, these data indicate that we have identified a novel transcription factor that is functionally important for the expression of at least two myeloid cell-specific genes.
Heydemann
A
A
Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA.
Boehmler
J H
JH
Simon
M C
MC
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D016384:Consensus Sequence; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009113:Muramidase / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011505:Protein-Tyrosine Kinases; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D051578:Proto-Oncogene Proteins c-fes; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D000099232:Proto-Oncogene Protein Spi-1
D004247:DNA; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D009113:Muramidase; D011505:Protein-Tyrosine Kinases; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D051578:Proto-Oncogene Proteins c-fes; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; C000715470:MAS1 protein, human; C496645:FES protein, human; C496646:Fes protein, mouse