CREB-binding protein transcription activation domain for enhanced transgene expression by a positive feedback system

► Positive feedback system using GAL4-VP16 is useful for transgene expression. ► GAL4-VP16 promotes its own expression as well as that of a reporter gene product. ► Transcription activation domains of endogenous proteins were fused to GAL4. ► The positive feedback systems employing the novel fusion proteins were examined. ► The CREB-binding protein functioned efficiently as an activator.