New Problems in RNA Polymerase II Transcription Initiation: Matching the Diversity of Core Promoters with a Variety of Promoter Recognition Factors

One of the key events in eukaryotic gene regulation is the assembly of general transcription factors (GTFs)4 and RNA polymerase II (Pol II) into a pre-initiation complex (PIC) at promoters. GTFs have been defined biochemically as a set of factors essential for accurate transcription initiation at a TATA box-containing viral promoter in vitro (1, 2). The textbook description states that the initiation of mRNA synthesis requires the recruitment and binding of the TATA-binding protein (TBP) as a component of the TFIID complex to a consensus sequence that is found in core promoters and is known as the TATA box (3).