APOLO LONG NONCODING RNA REGULATES STRESS RESONSE GENES IN ARABIDOPSIS

ARIEL, F.; MANAVELLA, P.; MAMMARELLA, F.; CRESPI, M.; CHRIST, A.; LUCERO, L.E.; BENHAMED, M.

ROSARIO

Simposio; Simposio de Genómica Funcional de Plantas; 2017

Noncoding RNAs have emerged as majorcomponents of the eukaryotic transcriptome. Genome-wide analyses revealed theexistence of thousands of long noncoding RNAs (lncRNAs) in several plantspecies. They are involved in a wide range of regulatory mechanisms impactingon gene expression, including chromatin remodeling, modulation of alternativesplicing, fine-tuning of miRNA activity, and the control of mRNA translation oraccumulation. Recently, dual noncoding transcription by alternative RNApolymerases was implicated in epigenetic and chromatin conformation dynamics.Reversible variations in the epigenome shape the genome topology inthree-dimensional space structure, directly influencing the transcriptionalresponses to developmental cues. It was shown that the Arabidopsis intergeniclncRNA (or lincRNA) APOLO istranscribed by RNA polymerases II and V in response to auxin, a phytohormonecontrolling numerous facets of plant development. This dual APOLO transcription regulates theformation of a chromatin loop encompassing the promoter of its neighboring genePID, a key regulator of polar auxintransport. Altering APOLO expressionaffects chromatin loop formation, dynamically shaping PID expression pattern. Genome-wide identification of APOLO?interacting loci revealed a directregulation of several stress-response genes in trans, uncovering a noncoding RNA-coordinated mechanism of plantdevelopmental plasticity.