Small noncoding RNA in Streptococci: From regulatory functions to drug development.

Streptococci are a genus of gram-positive coccus of spherical bacteria, including many commensal bacteria and opportunistic pathogens that threaten the public health system. Small noncoding RNAs (sRNAs) are a class of noncoding RNAs regulating gene expression via various regulatory mechanisms, which have been illustrated to play vital roles in regulations of virulence factor expressions. Recent advances in sequencing technology and bioinformatic analysis facilitated discovery of a myriad of sRNAs from pathogenic bacteria, revealing a variety of unique features that contribute to gene expressions and virulence regulations. Although various research studies have reported the regulatory functions of sRNAs in the virulence of bacterial species of the genus Streptococci, the common features of sRNAs in the pathogenesis of Streptococci remain unclear. This blocks the development of novel antistreptococcal antibiotics and antibacterial strategies. Here, we summarize the fundamental roles of Streptococcal sRNAs in pathogenic regulations, which advance mechanistic understanding of streptococcal infection associated diseases. Moreover, we discuss the prospects of sRNA acting as drug targets to combat bacterial antibiotic resistance.