The emerging role of bacterial regulatory RNAs in disease.

Pathogenic bacteria have evolved to sense their surrounding environments and regulate their gene expression to evade host immune defences and cause disease. RNA-mediated gene expression offers a fast and energy efficient alternative to conventional transcription factors. A myriad of regulatory RNAs have been identified, especially in pathogenic bacteria. However, whether these RNAs partake in disease remains largely unexplored. Here, we review current knowledge of regulatory RNAs in human-adapted upper respiratory tract pathogens. We propose that bacterial regulatory RNAs could play important roles in disease. Elucidating the function of regulatory RNAs and identifying polymorphisms among disease isolates would provide valuable insight into their pathogeneses. Finally, we discuss the outstanding issues of regulatory RNAs in research and their applications as drug targets, therapeutics, and in providing diagnostic information predictive of disease prognosis.