title: IL-2 negatively regulates IL-7 receptor alpha chain expression in activated T lymphocytes.
abstract: Interleukin (IL)-2 is a type I four-alpha-helical bundle cytokine that plays vital roles in antigen-mediated proliferation of peripheral blood T cells and also is critical for activation-induced cell death. We now demonstrate that IL-2 potently decreases expression of IL-7 receptor alpha chain (IL-7Ralpha) mRNA and protein. The fact that IL-7Ralpha is a component of the receptors for both IL-7 and thymic stromal lymphopoietin (TSLP) suggests that IL-2 can negatively regulate signals by each of these cytokines. Previously it was known that the IL-2 and IL-7 receptors shared the common cytokine receptor gamma chain, gamma(c), which suggested a possible competition between these cytokines for a receptor component. Our findings now suggest a previously unknown type of cross-talk between IL-2 and IL-7 signaling by showing that IL-2 signaling can diminish IL-7Ralpha expression via a phosphatidylinositol 3-kinase/Akt-dependent mechanism.
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008894:Milk Proteins; D020411:Oligonucleotide Array Sequence Analysis; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020395:Receptors, Interleukin-7 / Q000235:genetics* / Q000378:metabolism*; D050799:STAT5 Transcription Factor; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D015534:Trans-Activators / Q000172:deficiency / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D007376:Interleukin-2; D008894:Milk Proteins; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D012333:RNA, Messenger; D020395:Receptors, Interleukin-7; D050799:STAT5 Transcription Factor; D015534:Trans-Activators; C415350:interleukin-7 receptor, alpha chain; C494918:AKT1 protein, human