SPI1, Transcription factor PU.1, 31 kDa-transforming protein
Binds to the PU-box, a purine-rich DNA sequence (5-GAGGAA-3) that can act as a lymphoid-specific enhancer. This protein is a transcriptional activator that may be specifically involved in the differentiation or activation of macrophages or B-cells. Also binds RNA and may modulate pre-mRNA splicing.