MicroRNAs (miRNA) are part of a large class of noncoding RNAs with regulatory functions. They are small molecules of single strand RNA that act as potent post-transcriptional regulators of gene expression.
The discovery of miRNAs that regulate signaling pathways important in control of various pathophysiological processes has made this type of molecule occupies a position of great prominence in biological and biomedical research and is considered one of the most important discoveries of the post-genomic era.
MiRNAs, originally described in C. elegans in 1993, remained unexplored for nearly a decade. Since the discovery of the second miRNA in 2000, the let-7 miRNAs 6,000 were identified in more then 150 species, including viruses, plants, fungi and animals. In humans the number of miRNAs thus far exceeds 1,400.
MiRNAs perform the repression of protein synthesis by interacting with the region 3′não translated from messenger RNAs (mRNA) targets. For its small size and imperfect interaction with target mRNAs, miRNAs comprise a complex network of post-transcriptional regulation of gene expression. Even today, bioinformatics tools have identified new miRNA genes in the genome, and estimate the prediction of target mRNAs.
Expression analysis of miRNAs may be useful as a diagnostic and prognostic tool, since the expression pattern of miRNAs discriminates more effectively pathological samples than conventional methodologies which use the expression pattern of mRNAs. Furthermore, modulation of miRNAs in vivo has shown promising results in relation to the modulation of signaling pathways involved in disease processes.
The forced expression or specific inhibition of one miRNA have proved effective in restoring or stop signal transduction, restoring normal phenotype in several pathological conditions. Outside, the advances in this area include clinical trials, however miRNAs in translational research is still incipient in Brazil. The research groups involved in the creation of this Center for Research Support has contributed to publications and develop research projects with funding in this area, involving post-doctoral, undergraduate students and graduate. Parallel to the growth of international scientific production in the field of miRNA, the national publication has also increased recently, but the fraction of the country’s production comprises only 0.2% of 18,400 publications indexed in Medline (March/2012). Thus it is necessary to work together to implement and accelerate scientific knowledge in this area. The integration of Brazilian research groups will certainly accelerate this process and the proposed creation of the Center for Research Support miRNA will bring major advances in basic and translational research in the country.