Identification of miRNA biogenesis modulators by chemical genetics

MANAVELLA PA

Congreso; XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2010

MicroRNAs are post-transcriptional regulators that bind to complementary sequences of target mRNA transcripts, usually resulting in gene silencing. The production of miRNAs requires multiple and coordinated steps. Although a variety of proteins involved in their processing and function have been identified, their mutant phenotypes are not always the same. An alternative to traditional forward genetic screens is chemical genetics. This approach utilizes small molecules to perturb a signaling pathway, permitting the identification of relevant factors without a continuous perturbation in a gene product. Herein we report the development of a high-throughput assay for miRNA-mediated gene regulation and the identification of several miRNA inhibitors. The screening of a chemical library, compose by 10,000 structurally diverse small molecules, allowed us to identify a group of compounds with different levels and modes of inhibition. Measurement of endogenous miRNAs together with the expression level of their precursors and target genes confirmed the inhibitory effect. Additionally, the compounds have been tested for their ability to affect other small RNA pathways as well as non-plant pathways.