Roquin Defects Reveal a Role for the MicroRNA Machinery in Regulating Autoimmunity

Evidence gathered in the last few years has revealed how a class of small non-coding RNAs - microRNAs (miRNAs) - fine-tune gene expression post-transcriptionally, influencing the immunological repertoire, the size of mature lymphoid compartments and the threshold for lymphocyte selection and activation. More recently, the miRNA machinery has been shown to play an instrumental role in both the prevention and promotion of autoimmunity. Specifically, the Roquin pathway has emerged as a powerful negative regulator of systemic and organ-specific autoimmunity through miRNA-mediated control of T cell-expressed genes involved in T cell activation. Here we survey the evidence that miRNAs regulate immune responses relevant to the pathogenesis of autoimmunity and describe how Roquin acts in concert with T cellexpressed miRNAs to prevent lupus development.