Signals and nuclear factors that regulate the expression of interleukin-4 and interleukin-5 genes in helper T cells.
Mouse thymoma line EL-4 cells produce cytokines such as interleukin (IL)-2, IL-3, IL-4, IL-10, and granulocyte-macrophage colony-stimulating factor in response to phorbol 12-myristate 13-acetate (PMA). EL-4 cells also produce low levels of IL-5 when stimulated by PMA alone; however, cAMP greatly augments PMA-dependent IL-5 production. A transient transfection assay revealed that two signals, PMA and cAMP, are required for optimal activation of the IL-5 promoter. In contrast, cAMP almost completely inhibited the PMA-dependent activation of the endogenous IL-2 gene, as well as the transfected IL-2 promoter. These results indicate that the IL-5 gene is positively regulated by cAMP in a manner opposite to that for the IL-2 gene. One of the nuclear factors (NFs) that regulates the response of the IL-5 promoter to cAMP and PMA has properties similar to NF for activated t cell. The P sequence of the IL-4 gene, defined as a responsive element for PMA and calcium ionophore (A23187), shares sequence similarity with the NF kappa B and the NF-activated T cell binding sites. We attempted to determine whether NF(P), a nuclear factor specific for the P sequence, is related to NF-kappa B and nuclear factor for activated T cell (NF-AT). In electromobility shift assays both NF-kappa B (P65 or P65/P50 heterodimer) and NF-AT bound to the P sequence. However, sequence specificity of NF-AT was more similar to that of NF(P), and only a small amount of P65 was detected in NF(P). These results indicate that a component or components of NF-AT have the potential to reconstitute NF(P), whereas NF-kappa B alone does not account for NF(P) in Jurkat crude extract. Taken together, these results suggest that NF-AT-like factors are involved in the regulation of IL-4 and IL-5 genes.
Lee
H J
HJ
Department of Molecular and Developmental Biology, University of Tokyo, Japan.
Matsuda
I
I
Naito
Y
Y
Yokota
T
T
Arai
N
N
Arai
K
K
D000818:Animals; D001483:Base Sequence; D005786:Gene Expression Regulation; D006801:Humans; D015847:Interleukin-4 / Q000235:genetics*; D015848:Interleukin-5 / Q000235:genetics*; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000502:physiology; D012045:Regulatory Sequences, Nucleic Acid; D015398:Signal Transduction / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014157:Transcription Factors / Q000502:physiology
D015848:Interleukin-5; D016328:NF-kappa B; D014157:Transcription Factors; D015847:Interleukin-4