Eukaryotic Transcription

General Transcription Factors (GTFs)

Trans-acting protein factors that assemble with RNA Polymerase II at core promoter elements to form PIC

TFIID

A GTF containing TBP and ~13 TAFs that binds directly to the TATA box and core promoter sequences to anchor the PIC.

TBP (TATA-Binding Protein)

Subunit in TFIID that recognizes and binds to TATA box

TAFs (TBP-Associated Factors)

Subunits in TFIID that recognize additional core promoter motifs (Inr, DPE, MTE) to stabilize PIC assembly

TFIIA

A GTF that with TFIID helps anchor and stabilize complex at core promoter.

TFIIB

A GTF that binds to BRE sequence near TATA box to ensure accurate alignment of TSS with RNA Polymerase II

BRE (TFIIB Recognition Element)

A cis-acting DNA motif near the TATA box that is binding site for TFIIB

TFIIF

A GTF that associates with RNA Polymerase II and works alongside the Mediator complex to recruit the polymerase to the promoter assembly1012.

Mediator Complex

A coactivator complex that operates with TFIIF to recruit RNA Polymerase II to the promoter assembly1012.

TFIIE

A GTF that binds to the developing assembly and recruits TFIIH to complete the PIC

TFIIH

A GTF that unwinds at promoter (helicase subunit) and phosphorylates CTD tail of RNAP II

Phosphorylated CTD (C-Terminal Domain)

The tail of RNA Polymerase II that becomes active during transcription initiation to serve as a docking platform for pre-mRNA processing factors13.