ESE-1 Is a Novel Transcriptional Mediator of Angiopoietin-1 Expression in the Setting of Inflammation

• Published in: The Journal of biological chemistry 2004-03, Vol.279 (13), p.12794-12803
• Main Authors: Brown, Courtney, Gaspar, John, Pettit, Allison, Lee, Rebecca, Gu, Xuesong, Wang, Hong, Manning, Cathy, Voland, Carole, Goldring, Steven R., Goldring, Mary B., Libermann, Towia A., Gravallese, Ellen M., Oettgen, Peter
• Format: Article
• Language: English
• Subjects: Angiopoietin; Angiopoietin-1 - genetics; Angiopoietin-1 - metabolism; Animals; Arthritis, Rheumatoid - metabolism; Binding Sites; Blotting, Western; Cell Line; Cell Line, Tumor; Chemotaxis; Cytokines - metabolism; DNA - chemistry; DNA Mutational Analysis; DNA, Complementary - metabolism; DNA-Binding Proteins - metabolism; DNA-Binding Proteins - physiology; ESE-1 protein; Fibroblasts - metabolism; Gene Expression Regulation; Genes, Reporter; Genetic Vectors; Humans; Immunohistochemistry; Inflammation - metabolism; Luciferases - metabolism; Mice; Mutagenesis, Site-Directed; Mutation; NIH 3T3 Cells; Oligonucleotide Array Sequence Analysis; Oligonucleotides - chemistry; Promoter Regions, Genetic; Protein Binding; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins - physiology; Proto-Oncogene Proteins c-ets; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - metabolism; Transcription Factor AP-1 - metabolism; Transcription Factors - metabolism; Transcription Factors - physiology; Transcription, Genetic; Transcriptional Activation; Tumor Necrosis Factor-alpha - metabolism; Up-Regulation
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M308593200

Angiogenesis is a critical component of the inflammatory response associated with a number of conditions. Angiopoietin-1 (Ang-1) is an angiogenic growth factor that promotes the chemotaxis of endothelial cells and facilitates the maturation of new blood vessels. Ang-1 expression is up-regulated in response to tumor necrosis factor-α (TNF-α). To begin to elucidate the underlying molecular mechanisms by which Ang-1 gene expression is regulated during inflammation, we isolated 3.2 kb of the Ang-1 promoter that contain regulatory elements sufficient to mediate induction of the promoter in response to TNF-α, interleukin-1β, and endotoxin. Surprisingly, sequence analysis of this promoter failed to reveal binding sites for transcription factors that are frequently associated with mediating inflammatory responses, such as NF-κB, STAT, NFAT, or C/EBP. However, putative binding sites for ETS and AP-1 transcription factor family members were identified. Interestingly, among a panel of ETS factors tested in a transient transfection assay, only the ETS factor ESE-1 was capable of transactivating the Ang-1 promoter. ESE-1 binds to specific ETS sites within the Ang-1 promoter that are functionally important for transactivation by ESE-1. ESE-1 and Ang-1 are induced in synovial fibroblasts in response to inflammatory cytokines, with ESE-1 induction slightly preceding that of Ang-1. Mutation of a high-affinity ESE-1 binding site leads to a marked reduction in Ang-1 transactivation by ESE-1, inducibility by inflammatory cytokines, and DNA binding to the ESE-1 protein. Transcriptional profiling of cells transiently transfected with an ESE-1 expression vector demonstrates that the endogenous Ang-1 gene is directly inducible by ESE-1. Finally, Ang-1 and ESE-1 exhibit a similar and strong expression pattern in the synovium of patients with rheumatoid arthritis. Our results support a novel paradigm for the ETS factor ESE-1 as a transcriptional mediator of angiogenesis in the setting of inflammation.