摘要
Clustered organization of biosynthetic non-homologous genes is emerging as a characteristic feature of plant genomes.The co-regulation of clustered genes seems to largely depend on epigenetic reprogram-ming and three-dimensional chromatin conformation.In this study,we identified the long non-coding RNA(lncRNA)MARneral Silencing(MARS),localized inside the Arabidopsis marneral cluster,which con-trols the local epigenetic activation of its surrounding region in response to abscisic acid(ABA).MARS modulates the POLYCOMB REPRESSIVE COMPLEX 1(PRC1)component LIKE HETEROCHROMATIN PROTEIN 1(LHP1)binding throughout the cluster in a dose-dependent manner,determining H3K27me3 deposition and chromatin condensation.In response to ABA,MARS decoys LHP1 away from the cluster and promotes the formation of a chromatin loop bringing together the MARNERAL SYNTHASE 1(MRN1)locus and a distal ABA-responsive enhancer.The enrichment of co-regulated lncRNAs in clustered meta-bolic genes in Arabidopsis suggests that the acquisition of novel non-coding transcriptional units may constitute an additional regulatory layer driving the evolution of biosynthetic pathways.
基金
supported by a BBSRC grant(BB/L016966/1)to J.G.-M.and Saclay Plant Sciences-SPS(ANR-17-EUR-0007)and CNRS(Labora-toire International Associe NOCOSYM)to M.C.and F.A..T.R.was awarded a PhD scholarship from the French“Ministere de I'Enseignement superieur,de la Recherche et de I'nnovation.”。
