ASCO LONG NONCODING RNA MODULATES ALTERNATIVE SPLICING IN ARABIDOPSIS THALIANA

ARIEL, FEDERICO D.

Buenos Aires

Congreso; SAIB 2017; 2017

SAIB

Alternative splicing (AS) of pre-mRNAs represents a major mechanism boosting transcriptome andproteome complexity. In Arabidopsis, the long noncoding RNA ALTERNATIVE SPLICINGCOMPETITOR (lncRNA ASCO) was previously found to hijack the nuclear AS regulators NSRs tomodulate AS patterns during root development. Here, we showed by RNA-seq that the deregulationof ASCO impacts the expression levels of stress and defense-related genes, including severalmembers from the AP2/ERF and JAZ families of transcription factors. Furthermore, the knock-downof ASCO alters the AS pattern of certain stress-related pre-mRNAs, notably involved insenescence. Noteworthy, several pre-mRNAs alternatively spliced in ASCO-deregulated lines werenot affected in the nsra/b double mutants, suggesting that ASCO also modulates alternative splicingin an NSR-independent manner. Therefore, we adapted a chromatin-related technique (calledChromatin Isolation by RNA Purification, ChIRP) to what we called nuclear Protein Isolation by RNAPurification (nPIRP) followed by Mass Spectrometry, in order to identify ASCO-associated proteincomplexes. Our nPIRP results suggest that ASCO is recognized in vivo by several specific splicingfactors, as well as few stress- and phytohormone-related proteins. Altogether, our work indicatesthat ASCO modulates hormone and stress signaling via the regulation of alternative splicing ofspecific targets.