On the molecular characterization of a novel plant micro RNAs co-factor

TOMASSI, ARIEL H; MANAVELLA, PABLO A

Simposio; Fronteras en Biociencias 3; 2018

Post-transcriptional regulation of the gene expression mediated by microRNAs (miRNAs) controls numerous processes during plant development and adaptation to environment. Although in the last years several factors involved in miRNAs biogenesis and action were characterized, their specific mechanisms of action remain unclear. In our lab has been performed a genetic screening to identify new components of the miRNAs biogenesis and action machinery. By EMS mutagenesis in plants carrying a reporter system based on the Luciferase activity and its silencing by an aritficial miRNA, it has been identified around 30 miRNA deficient mutants. Among the still uncaractherized mutants of this screening, the M141 mutant plants presents an aberrant development phenotype, elevated levels of Luciferase activity and altered miRNAs and target genes levels. By SHOREmap sequencing of whole genome we identified mutations in 4 genes potentially responsible of the describe phenotype. Using molecular complementation we narrow the phenomenon to a gene encoding a protein of unknown function. Exploring its subcellular localization, subcellular colocalization and protein-protein interaction assays with well described miRNAs biogenesis factors, allowed us to postulate this protein as a possible novel co-factor of this pathway, although its specific function remains unrevealed.