RNA-binding protein involved in alternative pre-RNA splicing and in cytoplasmic stress granules formation . Shows a preference for uridine-rich RNAs . Activates splicing of alternative exons with weak 5' splice sites followed by a U-rich stretch on its own pre-mRNA and on TIA1 mRNA (By similarity). Promotes the inclusion of TIA1 exon 5 to give rise to the long isoform (isoform a) of TIA1 . Acts downstream of the stress-induced phosphorylation of EIF2S1/EIF2A to promote the recruitment of untranslated mRNAs to cytoplasmic stress granules (SG) . Possesses nucleolytic activity against cytotoxic lymphocyte target cells . May be involved in apoptosis .
Nucleus . Cytoplasm . Cytolytic granule . Cytoplasm, Stress granule . Nuclear import seems to be coupled to RNA polymerase II transcription and may be dependent on RNA-binding (By similarity). Accumulates in cytoplasmic stress granules (SG) following cellular damage (PubMed:10613902). .
Expressed in brain, heart, kidney, lung and skeletal muscle.