TFIIA is a component of the transcription machinery of RNA polymerase II and plays an important role in transcriptional activation. TFIIA in a complex with TBP mediates transcriptional activity. TFIIA is a heterodimer composed of the large TOA1 and a small TOA2 subunits. Interacts with TBP. Interacts with TAF11. Interacts with KAP122. Imported to nucleus via interaction with KAP122. Present with 3910 molecules/cell in log phase SD medium. Belongs to the TFIIA subunit 2 family.