Switch-like regulation of signal transduction by small RNA-mediated quorum sensing

Quorum sensing (QS) is a mechanism by which bacteria produce, release, and then detect and respond to biosignals called autoinducers (AIs). There are multiple feedback loops in the QS system of Vibrio harveyi. However, how these feedback loops function to control signal processing remains unclear. In this paper, we present a computational model for switch-like regulation of signal transduction by small regulatory RNA-mediated QS based on intertwined network involving AIs, LuxO, LuxU, Qrr sRNAs, and LuxR. In agreement with experimental observations, the model suggests that different feedbacks play critical roles in the switch-like regulation. Our results reveal that Vibrio harveyi uses multiple feedbacks to precisely control signal transduction.