Translational regulation: identification of the site on bacteriophage T4 rIIB mRNA recognized by the regA gene function.

The bacteriophage T4 gene regA encodes a protein that diminishes the expression of many unlinked early T4 genes. Previous work demonstrated that regA-mediated repression occurs after transcription. We report here on the identification of the target site on one regA-sensitive mRNA, the message encoding the phage T4 rIIB protein. The target for regA-mediated action overlaps the translational initiation domain of the rIIB messenger. The regA protein may be a repressor that operates translationally on a significant and interesting set of early phage T4 mRNAs.