Plays a role in alternative splicing of pre-mRNAs, possibly by contributing to the selection of non-consensus donor sites. Interacts with spliceosomal Sm proteins (PubMed:17656373). Interacts with LUC7L2 and SNRNP70, which suggests a role as a spliceosome component (By similarity). Colocalizes with LUC7L2 and SNRNP70 in nuclear speckles.