Nucleotide sequence of the mouse CD80 (A) and CD86 (B) promoters. The position of the transcription start site is marked by (*). In addition to the consensus Ets-family protein binding sequence (GGAA; boxed), AGAA²⁵  (boxed) is also bound with PU.1. The IRF recognition sequence (AANNGAAA)–like is underlined. PU.1 binds genomic DNA via GGAA and AGAA as a monomer and GGAANNGAAA as a heterodimer with IRF4 or IRF8.⁵⁴