STATs Find That Hanging Together Can Be Stimulating

Abstract
A report in this week's issue of Science by Xu et al . ( p. 794 ) shows that homodimers of various kinds of STATs (signal transducers and activators of transcription) bind to regulatory regions of the gene for the interferon-γ gene, each with a slightly different binding site. In their Perspective, Leung, Li, and Stark explain how these cooperating STAT dimers, which interact via their NH 2 terminals, can determine the specificity of the cytokine response.