Failure of Translation Initiation of the Next Gene Decouples Transcription at Intercistronic Sites and the Resultant mRNA Generation

Abstract

Transcription of operons is initiated at the promoter of the first gene in the operon, continues through cistron junctions, and terminates at the end of the operon, generating a full-length mRNA. Here, we show that Rho-dependent termination of transcription occurs stochastically at a cistron junction, generating a stable mRNA that is shorter than the full-length mRNA. We further show that stochastic failure in translation initiation of the next gene, rather than the failure of translation termination of the preceding gene, causes the Rho-dependent termination. Thus, stochastic failure in translation initiation at the cistron junction causes the promoter-proximal gene to be transcribed more than promoter-distal genes within the operon.