A small RNA serving both the Hfq and CsrA regulons.

The abundant RNA-binding proteins CsrA and Hfq each impact bacterial physiology by working in conjunction with small RNAs to control large post-transcriptional regulons. The small RNAs involved were considered mechanistically distinct, regulating mRNAs either directly through Hfq-mediated base-pairing or indirectly by sequestering the global translational repressor CsrA. In this issue of Genes & Development, Jørgensen and colleagues (pp. 1132-1145) blur these distinctions with a dual-mechanism small RNA that acts through both Hfq and CsrA to regulate the formation of bacterial biofilms.