Small RNAs in major foodborne pathogens: from novel regulatory activities to future applications

Small regulatory RNAs (sRNAs) are involved in post-transcriptional control of important cellular processes and contribute to the success of a pathogen. Here, we use studies primarily selected from Salmonella enterica and Listeria monocytogenes to illustrate the current status of sRNA biology in important foodborne pathogens. We discuss how the regulatory activities of sRNAs can be affected by base pairing RNAs known as ‘sponge RNAs’, or by RNA-binding proteins, such as the newly discovered sRNA chaperone ProQ. Furthermore, we highlight recent findings for sRNAs with regulatory roles during infection, some of which are present in multiple copies, designated ‘sibling sRNAs’. Importantly, knowledge on sRNA-mediated regulation can be exploited for biotechnological applications, such as in generating gene knockdowns to promote desired traits.