Protein of the nuclear speckles that regulates RNA degradation and export from the nucleus through its interaction with MTREX an essential factor directing various RNAs to exosomal degradation (PubMed:30842217). Changes the conformation of MTREX, precluding its association with the nuclear exosome and interaction with proteins required for its function in RNA exosomal degradation (PubMed:30842217). Negatively regulates, for instance, the degradation of mRNAs and lncRNAs by inhibiting their MTREX-mediated recruitment to nuclear exosome (PubMed:30842217). By preventing the degradation of RNAs in the nucleus, it promotes their export to the cytoplasm (PubMed:30842217). U5 snRNP-associated RNA splicing factor which is required for efficient splicing of CEP131 pre-mRNA and plays an important role in centrosome maturation, integrity and function during mitosis (PubMed:30538148). Suppresses intron retention in a subset of pre-mRNAs containing short, GC-rich introns with relatively weak 5′ and 3′ splice sites (PubMed:30538148). Plays a role in DNA damage response (PubMed:29902117).
