MicroRNA control of lymphocyte differentiation and function.

MicroRNAs (miRNAs) are a class of endogenous, non-coding regulatory RNAs that control gene regulation by guiding silencing protein complexes to mRNA in a sequence-dependent manner. In this way miRNAs are able to repress gene expression post-transcriptionally by affecting mRNA stability or translation. These ubiquitous molecules play central roles in a wide range of biological processes, including cell proliferation, differentiation and apoptosis. Within the context of the immune system, genetic studies have identified distinct roles for specific miRNAs in gene regulation during development, activation and maturation. Conversely, dysregulation of miRNA expression has been specifically correlated with cancer. This review outlines our current understanding of miRNA function in lymphocytes as it impacts expression of protein-coding genes in the context of proper development, as well as oncogenesis.