MicroRNAs and their implications in toxicological research.

MicroRNAs (miRNAs) are non-coding regulatory RNA molecules that bind target messenger RNAs (mRNA) and suppress their translation into proteins. When an organism is exposed to a toxic compound, cells respond by altering the pattern of gene expression, including miRNAs. Altered miRNA expression affects protein translation, which in turn alters cellular physiology causing adverse biological effects. Moreover, different types of cellular stress have been shown to affect miRNA expression as a mechanism of adaptation or tolerance to stress factors in order to survive. Besides an updated theoretical background concerning miRNAs biology, biogenesis, function, and roles in disease; this mini review provides an overview of miRNAs response to exogenous agents such as environmental stressors and toxic compounds. The implications of miRNAs in toxicogenomics as well as the new avenues of research of miRNAs in toxicology are discussed. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.