RNA-binding protein involved in pre-mRNA splicing (PubMed:19641227). Interacts with the PRP19C/Prp19 complex/NTC/Nineteen complex which is part of the spliceosome (PubMed:19641227). Involved in regulating splice site selection (PubMed:19641227). Binds preferentially RNA with A/C rich sequences and poly-C stretches (PubMed:23144703).