Microbiologists at the University of Jena in Germany have found a new mechanism of autoregulation during gene expression that relies on small regulatory ribonucleic acids (sRNAs) and the major endoribonuclease RNase E. Their results were published in eLife.
Commonly studied gene regulatory mechanisms include transcription factors and how they repress transcription by blocking access of RNA polymerase to the promoter region. While this mode of negative autoregulation is universally present in living organisms, the role of sRNA and major endoribonuclease RNase E hadn’t been characterized.
The team used TIER-seq analysis (transiently-inactivating-an-endoribonuclease), followed by RNA-seq, to address the regulatory role of RNase E in Vibrio cholerae at genome-wide level. Through this study, they successfully identified nearly 25,000 RNase E-sensitive sites and revealed the presence of stable sRNas (OppZ and CarZ). Examination of these sRNAs showed that they can act in an autoregulatory manner, by reducing the expression of mRNAs produced in the same genetic locus.
"This autoregulation controls gene expression—that means, the proteins are synthesized based on genetic information. Bacteria use this process to adapt to their environment for example," concludes researcher Kai Papenfort.