The Arabidopsis lncRNA ASCO modulates the transcriptome through interaction with splicing factors

ROMERO-BARRIOS, NATALI; CHRIST, AURELIE; HUGUET, STEPHANIE; ARIEL, FEDERICO; RIGO, RICHARD; MOISON, MICHAEL; BENHAMED, MOUSSA; CHARON, CELINE; BAZIN, JÉRÉMIE; LUCERO, LEANDRO; BLEIN, THOMAS; CRESPI, MARTIN

EMBO REPORTS

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2020

1469-221X

Alternative splicing (AS) is a major source of transcriptome diversity.Long noncoding RNAs (lncRNAs) have emerged as regulatorsof AS through different molecular mechanisms. In Arabidopsisthaliana, the AS regulators NSRs interact with the ALTERNATIVESPLICING COMPETITOR (ASCO) lncRNA. Here, we analyze the effectof the knock-down and overexpression of ASCO at the genomewidelevel and find a large number of deregulated and differentiallyspliced genes related to flagellin responses and biotic stress.In agreement, ASCO-silenced plants are more sensitive to flagellin.However, only a minor subset of deregulated genes overlaps withthe AS defects of the nsra/b double mutant, suggesting an alternativeway of action for ASCO. Using biotin-labeled oligonucleotidesfor RNA-mediated ribonucleoprotein purification, we show thatASCO binds to the highly conserved spliceosome component PRP8a.ASCO overaccumulation impairs the recognition of specificflagellin-related transcripts by PRP8a. We further show that ASCOalso binds to another spliceosome component, SmD1b, indicatingthat it interacts with multiple splicing factors. Hence, lncRNAs mayintegrate a dynamic network including spliceosome core proteins,to modulate transcriptome reprogramming in eukaryotes.