Autocrine induction of the human pro-IL-1beta gene promoter by IL-1beta in monocytes.
IL-1beta is produced primarily by activated monocytes/macrophages. We report in this study that IL-1beta induces the human pro-IL-1beta (IL1B) gene promoter in human THP-1 monocytic cells. The -131 to +12 minimal IL1B promoter was induced by IL-1beta in a dose-dependent manner. The promoter possesses two important transcription factor binding motifs, one for an ETS family transcription factor Spi-1 (PU.1), and the other a binding site for NF-IL6 (CCAAT/enhancer binding protein beta). Autocrine promoter activity was completely inhibited by mutation of the Spi-1 site. Mutation of the NF-IL6 binding motif caused partial loss of activity. EMSAs using THP-1 cell nuclear extracts indicated that IL-1beta significantly induced Spi-1 binding to its target site within the IL1B promoter that was maximal at 1 h after stimulation, correlating with the kinetics of IL-1beta induction. The importance of Spi-1 was supported by our observation that Spi-1-deficient EL4 thymocytes exhibited IL-1beta-induced activity only after transfection with a Spi-1 expression vector. Moreover, TNFR-associated factor 6 also required Spi-1 to activate the promoter. Transfection studies using Spi-1 mutant constructs showed that the TATA-binding protein binding and glutamine-rich domains of Spi-1 were important for IL-1beta induction, whereas LPS induction required the proline, glutamic acid, serine, and threonine-rich domain containing serine 148 as well as the TATA-binding protein and glutamine-rich domains. We conclude that the IL1B promoter is an IL-1beta-responsive sequence as a result of its ability to bind Spi-1 in response to IL-1beta.
Toda
Yoko
Y
First Department of Internal Medicine, School of Medicine, and School of Health Sciences, University of Occupational and Environmental Health, Kitakyushu, Japan.
Tsukada
Junichi
J
Misago
Masahiro
M
Kominato
Yoshihiko
Y
Auron
Philip E
PE
Tanaka
Yoshiya
Y
D019898:Autocrine Communication; D001665:Binding Sites; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000737:chemistry / Q000502:physiology; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000737:chemistry; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology*; D009000:Monocytes / Q000276:immunology*; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000096:biosynthesis / Q000235:genetics*; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000502:physiology; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D035181:TATA-Box Binding Protein; D048029:TNF Receptor-Associated Factor 6; D015534:Trans-Activators / Q000737:chemistry / Q000502:physiology; D014157:Transcription Factors / Q000737:chemistry; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D000099232:Proto-Oncogene Protein Spi-1
D022782:CCAAT-Enhancer-Binding Protein-beta; D004268:DNA-Binding Proteins; D007375:Interleukin-1; D011498:Protein Precursors; D011506:Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D035181:TATA-Box Binding Protein; D048029:TNF Receptor-Associated Factor 6; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; C043830:interleukin 1 precursor