ETS-1 transcription factor binds cooperatively to the palindromic head to head ETS-binding sites of the stromelysin-1 promoter by counteracting autoinhibition.
Stromelysin-1 (matrix metalloproteinase-3) is a member of the matrix metalloproteinase family. Regulation of its gene expression is critical for tissue homeostasis. Patterns of increased co-expression of stromelysin-1 and ETS-1 genes have been observed in pathological processes. Stromelysin-1 promoter is transactivated by ETS proteins through two palindromic head to head ETS-binding sites, an unusual configuration among metalloproteinase promoters. By using surface plasmon resonance, electrophoretic mobility shift assay, and photo-cross-linking, we showed that full-length human ETS-1 (p51) binds cooperatively to the ETS-binding site palindrome of the human stromelysin-1 promoter, with facilitated binding of the second ETS-1 molecule to form an ETS-1.DNA.ETS-1 ternary complex. The study of N-terminal deletion mutants allowed us to conclude that cooperative binding implied autoinhibition counteraction, requiring the 245-330-residue region of the protein that is encoded by exon VII of the gene. This region was deleted in the natural p42 isoform of ETS-1, which was unable to bind cooperatively to the palindrome. Transient transfection experiments showed a good correlation between DNA binding and promoter transactivation for p51. In contrast, p42 showed a poorer transactivation, reinforcing the significance of cooperative binding for full transactivation. It is the first time that ETS-1 was shown to be able to counteract its own autoinhibition.
Baillat
David
D
CNRS Unité Mixte de Recherche 8526, Institut de Biologie de Lille, Institut Pasteur de Lille, B.P. 447, 1 Rue Calmette, 59021 Lille Cedex, France.
Bègue
Agnès
A
Stéhelin
Dominique
D
Aumercier
Marc
M
D001483:Base Sequence; D001665:Binding Sites; D004247:DNA; D024202:Electrophoretic Mobility Shift Assay; D005822:Genetic Vectors; D006801:Humans; D019278:Matrix Metalloproteinase 3 / Q000235:genetics* / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D010777:Photochemistry; D011485:Protein Binding; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D050783:Proto-Oncogene Proteins c-ets; D020349:Surface Plasmon Resonance; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015533:Transcriptional Activation
C494041:ETS1 protein, human; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D014157:Transcription Factors; D004247:DNA; D019278:Matrix Metalloproteinase 3