A SITE IN THE BACTERIOPHAGE-T4 MAJOR HEAD PROTEIN GENE THAT CAN PROMOTE THE INHIBITION OF ALL TRANSLATION IN ESCHERICHIA-COLI

The cryptic DNA element, e14, synthesizes a protein, Lit, which can inhibit gene expression late in T4 bacteriophage development. This inhibition is due to the interaction between the Lit protein and a short region, the gol region, within gene 23, the major head protein gene of phage T4. We have constructed plasmids in which the gol region is transcribed from the lac promoter and fused translationally and transcriptionally to lacZ and cat (chloramphenicol acetyltransferase). These fusion plasmids were used to demonstrate that, in the presence of Lit protein, the gol region inhibits the expression of genes downstream in the same transcription unit. This local inhibition does not require the gene 23 polypeptide from the gol region. In addition, inducing the transcription and translation of the gol region in the presence of Lit protein causes an immediate global inhibition of all translation in Escherichia coli. This global inhibition does require the gene 23 polypeptide. No more than 75 base-pairs of DNA from the gol region are required for both the local and global inhibitions. The gol region sequence contains a short dyad symmetry. However, it is the sequence of bases in the region of dyad symmetry and not the ability to form a hairpin in the RNA that is required for gol region activity. © 1990 Academic Press Limited.