Identification of FUS RNA targets in HeLa cells

We identified a landscape of FUS-binding RNA targets in HeLa cells. The majority of the FUS binding sites are in introns of pre-mRNAs and less are in exons and untranslated regions. Significant FUS binding in introns flanking cassette exons, long intron (>100kb) containing transcripts and noncoding RNAs were detected in our study. We specifically determined the function of FUS in regulating the alternative splicing of cassette exons. The top FUS-associated cassette exon is exon 7 of the pre-mRNA of FUS itself. We demonstrated that FUS is a repressor of its own exon 7 splicing. FUS autoregulates its own protein levels by exon 7 alternative splicing and nonsense mediated decay. Moreover, Amyotrophic Lateral Sclerosis (ALS) linked FUS mutants are deficient in FUS autoregulation. Overall design: CLIP-seq of FUS in HeLa cells