Pip, a lymphoid-restricted IRF, contains a regulatory domain that is important for autoinhibition and ternary complex formation with the Ets factor PU.1.

摘要: Pip is a lymphoid-restricted IRF transcription factor that recruited to composite elements within immunoglobulin light-chain gene enhancers through specific interaction with the Ets PU.1. We have examined transcriptional regulatory properties of as well requirements for its PU.1 and DNA form ternary complex. demonstrate dichotomous regulator; it specifically stimulates in conjunction PU.1, but represses alpha/beta-interferon-inducible absence Thus, during B-cell activation differentiation, may function both an activator promote B cell-specific expression repressor inhibit antiproliferative effects alpha/beta-interferons. Mutational analysis reveals carboxy-terminal segment important autoinhibition binding complex formation. A domain containing this confers PU.1-dependent activity DNA-binding related family member, p48. On basis these other data we propose model PU.1/Pip