Regulation of cytokine gene expression: gene activation in type I IFN and IL-2 systems

Cytokines represent essential soluble mediators in cell-to-cell communication and they are known to play crucial roles in many biological processes, including viral infection, inflammation and immunity. We have been focusing on two cytokine systems, the interferon (IFN) and interleukin 2 (IL-2) systems each of which respectively plays a key role in viral infections and the immune response. In both cases, expression of those cytokines and, in the case of IL-2 system, the receptor is tightly regulated at the transcriptional level. Recent studies in our laboratory as well as others have uncovered the mechanism(s) operating in the regulation of those genes and have provided further insights on how the two cytokine systems operate and what is the biological significance of gene regulation in these systems. Here, we summarize the current understanding of the IFN system and IL-2 system in the context of host defense against viral infections and T cell neoplasms, respectively.