期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2003
卷号：100
期号：7
页码：4096-4101
DOI：10.1073/pnas.0630562100
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Transcription of the tumor necrosis factor (TNF) gene is rapidly and transiently induced by lipopolysaccharide in cells of monocyte/macrophage lineage. Previous studies have suggested that in the mouse, multiple NF-{kappa}B/Rel-binding sites contribute to the TNF transcriptional response to LPS. But the role of these regulatory elements in transcriptional activation of the TNF- gene in human monocytes remains unclear. Previously, a transcription factor, termed lipopolysaccharide-induced TNF- factor (LITAF), was found to regulate TNF- gene expression. However, the specific protein domain(s) of human (h)LITAF that interact with the hTNF- promoter had not been identified. In this study, we identify by footprinting a sequence motif, CTCCC (-515 to -511), within the TNF- promoter that binds to hLITAF. We also identify the region of hLITAF (amino acids 165-180) that was named peptide B and specifically mediates binding to the hTNF- promoter. When THP-1 cells were stimulated with this peptide B, it was sufficient to induce TNF- secretion. Induction of TNF- transcription by LPS or peptide B depended on the presence of the -515 to -511 promoter region, which was found to be essential for hLITAF binding. Together, these findings help to clarify the mechanism of hLITAF/hTNF- interaction and the manner by which hLITAF contributes to hTNF- regulation in an attempt to design new pharmacological interventions to address TNF-related diseases.
关键词：lipopolysaccharide-induced tumor necrosis factor-α factor‖electrophoretic mobility-shift assay‖DNA-binding site
