Tags: Protein.
Transcription factor IIB (TFIIB) is one of several general transcription factors that make up the RNA polymerase II preinitiation complex. It is encoded by the TFIIB gene.Transcription factor IIB localizes to the nucleus where it forms a complex (the DAB complex) with transcription factors IID and IIA. The protein serves as a bridge between transcription factor IID which initially recognizes the promoter sequence and RNA polymerase II.