Targeting riboswitches with synthetic small RNAs for metabolic engineering

Abstract

Our growing knowledge of the diversity of non-coding RNAs in natural systems and our deepening knowledge of RNA folding and function have fomented the rational design of RNA regulators. Based on that knowledge, we designed and implemented a small RNA (sRNA) tool to target bacterial riboswitches and activate gene expression. The synthetic sRNA is suitable for regulation of gene expression both in cell-free and in cellular systems. It targets riboswitches to promote the antitermination folding regardless the cognate metabolite concentration. Therefore, it prevents transcription termination increasing gene expression up to 103-fold. We successfully used sRNA arrays for multiplex targeting of riboswitches. Finally, we used the synthetic sRNA to engineer an improved riboflavin producer strain. The easiness to design and construct, and the fact that the riboswitch-targeting sRNA works as a single genome copy, make it an attractive tool for engineering industrial metabolite-producing strains. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/449321v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@11437b3org.highwire.dtl.DTLVardef@54e712org.highwire.dtl.DTLVardef@e657aorg.highwire.dtl.DTLVardef@1286b30_HPS_FORMAT_FIGEXP M_FIG C_FIG