The power of small RNAs: A comprehensive review on bacterial stress response and adaptation

Bacteria employ a wide range of RNA-based regulatory systems to adapt to various environmental stressors. Among these, small non-coding RNAs (sRNAs) have emerged as critical regulators of gene expression. These compact RNA molecules modulate numerous cellular functions, including stress adaptation, biofilm development, and virulence. By acting primarily at the post-transcriptional level, sRNAs enable bacteria to swiftly adjust gene expression in response to external challenges. One key mechanism of sRNA action is translational repression, which includes the regulation of toxin-antitoxin systems pathways essential for bacterial persistence and antibiotic resistance. Additionally, sRNAs orchestrate the expression of genes involved in biofilm formation, enhancing surface adhesion, extracellular matrix production, and resistance to antimicrobial agents. Bacterial outer membrane vesicles (OMVs) also play a significant role in stress adaptation and intercellular communication. These vesicles transport a complex cargo of proteins, lipids, and nucleic acids, including sRNAs. The transfer of sRNAs through OMVs can modulate the physiology of neighboring bacterial cells as well as host cells, highlighting their role in cross-kingdom signaling. sRNAs serve as versatile and potent regulatory elements that support bacterial survival under hostile conditions. Advancing our understanding of sRNA-mediated networks offers promising avenues for uncovering bacterial pathogenesis and developing innovative antimicrobial therapies.