Identification of a yeast protein with properties similar to those of the immunoglobulin heavy-chain enhancer-binding protein NF-muE3.

We demonstrate that Saccharomyces cerevisiae cells possess a 33-41-kilodalton protein with DNA-binding properties remarkably similar to those of the immunoglobulin enhancer-binding protein NF-muE3. We further show that the muE3-binding site functions as an upstream activating sequence in yeast cells, stimulating transcription from a truncated CYC1 promoter. These data suggest that the yeast protein, designated YEB-3, and NF-muE3 are functionally related and perhaps evolutionarily conserved.