DNA-binding and transcriptional activation properties of the EWS-FLI-1 fusion protein resulting from the t(11;22) translocation in Ewing sarcoma.
The 5' half of the EWS gene has recently been described to be fused to the 3' regions of genes encoding the DNA-binding domain of several transcriptional regulators, including ATF1, FLI-1, and ERG, in several human tumors. The most frequent occurrence of this situation results from the t(11;22)(q24;q12) chromosome translocation specific for Ewing sarcoma (ES) and related tumors which joins EWS sequences to the 3' half of FLI-1, which encodes a member of the Ets family of transcriptional regulators. We show here that this chimeric gene encodes an EWS-FLI-1 nuclear protein which binds DNA with the same sequence specificity as the wild-type parental FLI-1 protein. We further show that EWS-FLI-1 is an efficient sequence-specific transcriptional activator of model promoters containing FLI-1 (Ets)-binding sites, a property which is strictly dependent on the presence of its EWS domain. Comparison of the properties of the N-terminal activation domain of FLI-1 to those of the EWS domain of the fusion protein indicates that EWS-FLI-1 has altered transcriptional activation properties compared with FLI-1. These results suggest that EWS-FLI-1 contributes to the transformed phenotype of ES tumor cells by inducing the deregulated and/or unscheduled activation of genes normally responsive to FLI-1 or to other close members of the Ets family. ES and related tumors are characterized by an elevated level of c-myc expression. We show that EWS-FLI-1 is a transactivator of the c-myc promoter, suggesting that upregulation of c-myc expression is under control of EWS-FLI-1.
Bailly
R A
RA
Laboratoire d'Oncologie Virale et Cellulaire, Centre National de la Recherche Scientifique, URA 1443, Institut Curie, Orsay, France.
Bosselut
R
R
Zucman
J
J
Cormier
F
F
Delattre
O
O
Roussel
M
M
Thomas
G
G
Ghysdael
J
J
D000595:Amino Acid Sequence; D001483:Base Sequence; D001859:Bone Neoplasms / Q000235:genetics*; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11; D002892:Chromosomes, Human, Pair 22; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D005796:Genes; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D051789:Proto-Oncogene Protein c-fli-1; D011518:Proto-Oncogene Proteins / Q000302:isolation & purification / Q000378:metabolism; D050783:Proto-Oncogene Proteins c-ets; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000378:metabolism*; D015183:Restriction Mapping; D012512:Sarcoma, Ewing / Q000235:genetics*; D015534:Trans-Activators / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D014178:Translocation, Genetic
D017931:DNA Primers; D004268:DNA-Binding Proteins; D051789:Proto-Oncogene Protein c-fli-1; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D014157:Transcription Factors