Characterization of a novel negative regulatory element in the human interleukin 4 promoter

• Published in: Leukemia Vol. 14; no. 4; pp. 629 - 635
• Main Authors: GEORAS, S, CUMBERLAND, J, BURKE, T, PARK, E, ONO, S, CASOLARO, V
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 01.04.2000; Nature Publishing Group
• Subjects: Binding Sites; Biological and medical sciences; Control; Crosslinking; Cytokines; Deoxyribonucleic acid; DNA; DNA Mutational Analysis; DNA, Neoplasm - genetics; DNA, Neoplasm - metabolism; DNA-Binding Proteins - metabolism; Down-regulation; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gel electrophoresis; Gene expression; Gene Expression Regulation; Gene Expression Regulation, Neoplastic; Genes, Reporter; Genetic aspects; Genetics of the immune response; Health aspects; Hematologic and hematopoietic diseases; Hematopoiesis; Humans; Immune response; Immune response (cell-mediated); Immunobiology; Interleukin 4; Interleukin-4 - biosynthesis; Interleukin-4 - genetics; Jurkat Cells; Leukemia; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Lymphoblasts; Lymphocytes; Macromolecular Substances; Medical sciences; Molecular modelling; Molecular Weight; Mutation; Neoplasm Proteins - biosynthesis; Neoplasm Proteins - genetics; NF-AT protein; NFATC Transcription Factors; Nuclear Proteins; Physiological aspects; Promoter Regions, Genetic - genetics; Recombinant Fusion Proteins - biosynthesis; Recombinant Fusion Proteins - genetics; Reporter gene; Repressor Proteins - isolation & purification; Repressor Proteins - metabolism; Sequence Alignment; Sequence Deletion; Sequence Homology, Nucleic Acid; Sodium lauryl sulfate; Transcription factors; Transcription Factors - metabolism; Transcriptional Activation; Transfection; Tumors; United States; Immune response; Transcription; Pathogenesis; Leukemia; Cytokine; P element; Malignant hemopathy; Cellular immunity; Review; Interleukin 4; Lymphoproliferative syndrome; Genetics; Regulatory sequence; Molecular biology
• ISSN: 0887-6924; 1476-5551
• DOI: 10.1038/sj.leu.2401712

Interleukin 4 (IL-4) is a multifunctional cytokine that plays an important role in hematopoiesis, tumor cell growth, and cellular immune responses. Expression of the IL-4 gene is tightly controlled at the level of gene transcription, and many positive regulatory cis-elements have been identified in the proximal IL-4 promoter region. Relatively little is known about factors that downregulate IL-4 transcription. We performed a detailed deletional analysis of the proximal human IL-4 promoter and studied reporter gene activity in transiently transfected Jurkat T lymphoblasts. In this report, we characterize a novel negative regulatory element (termed P2 NRE) that is adjacent to a binding site for nuclear factor of activated T cells. Mutation of P2 NRE significantly enhanced the activity of a 175 base pair IL-4 promoter construct in transiently transfected Jurkat T lymphoblasts. Using nuclear extracts from Jurkat cells, we identify a candidate factor (termed Rep-1) that binds uniquely to the P2 NRE in DNA-binding assays. Rep-1 is not related to other factors previously shown to interact with the IL-4 promoter, and by UV cross-linking and SDS-PAGE analysis, we found that it migrates with a molecular mass of approximately 150 kDa. Characterizing the molecular mechanisms responsible for downregulating the IL-4 promoter should enhance our understanding of IL-4-gene dysregulation in disease states.