Characterization and analysis of the proximal Janus kinase 3 promoter.
Janus kinase 3 (Jak3) is a nonreceptor tyrosine kinase essential for signaling via cytokine receptors that comprise the common gamma-chain (gammac), i.e., the receptors for IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21. Jak3 is preferentially expressed in hemopoietic cells and is up-regulated upon cell differentiation and activation. Despite the importance of Jak3 in lymphoid development and immune function, the mechanisms that govern its expression have not been defined. To gain insight into this issue, we set out to characterize the Jak3 promoter. The 5'-untranslated region of the Jak3 gene is interrupted by a 3515-bp intron. Upstream of this intron and the transcription initiation site, we identified an approximately 1-kb segment that exhibited lymphoid-specific promoter activity and was responsive to TCR signals. Truncation of this fragment revealed that core promoter activity resided in a 267-bp fragment that contains putative Sp-1, AP-1, Ets, Stat, and other binding sites. Mutation of the AP-1 sites significantly diminished, whereas mutation of the Ets sites abolished, the inducibility of the promoter construct. Chromatin immunoprecipitation assays showed that histone acetylation correlates with mRNA expression and that Ets-1/2 binds this region. Thus, transcription factors that bind these sites, especially Ets family members, are likely to be important regulators of Jak3 expression.
Aringer
Martin
M
Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Hofmann
Sigrun R
SR
Frucht
David M
DM
Chen
Min
M
Centola
Michael
M
Morinobu
Akio
A
Visconti
Roberta
R
Kastner
Daniel L
DL
Smolen
Josef S
JS
O'Shea
John J
JJ
D020121:5' Untranslated Regions / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*; D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D019556:COS Cells; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation / Q000276:immunology; D006367:HeLa Cells; D006801:Humans; D053616:Janus Kinase 3; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009928:Organ Specificity / Q000235:genetics; D011401:Promoter Regions, Genetic; D011505:Protein-Tyrosine Kinases / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger / Q000032:analysis / Q000737:chemistry; D011948:Receptors, Antigen, T-Cell / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D024363:Transcription Initiation Site
D020121:5' Untranslated Regions; C494041:ETS1 protein, human; D050784:Proto-Oncogene Protein c-ets-1; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D011505:Protein-Tyrosine Kinases; C507933:JAK3 protein, human; D053616:Janus Kinase 3