TAF1A
Description
The TAF1A (TATA-box binding protein associated factor, RNA polymerase I subunit A) is a protein-coding gene located on chromosome 1.
TAF1A is an enzyme encoded by the TAF1A gene in humans. It is essential for the initiation of transcription by RNA polymerase I. TAF1A forms part of a complex called SL1, which includes the TATA-binding protein (TBP) and three TBP-associated factors (TAFs) specific for RNA polymerase I. SL1 binds to the core promoter of ribosomal RNA genes, positioning the polymerase correctly and acting as a channel for regulatory signals. TAF1A is the smallest SL1-specific TAF. Two transcript variants encoding different isoforms have been identified.
TAF1A is a component of the SL1/TIF-IB complex, which plays a crucial role in assembling the pre-initiation complex (PIC) during RNA polymerase I-dependent transcription. The speed of PIC formation is primarily determined by how quickly SL1/TIF-IB binds to the rDNA promoter. SL1/TIF-IB also helps stabilize the nucleolar transcription factor 1 (UBTF) on rDNA. The formation of SL1/TIF-IB prevents the TATA-binding protein (TBP) from interacting with TFIID subunits.
TAF1A is also known as MGC:17061, RAFI48, SL1, TAFI48.
