Involved in pre-mRNA splicing through regulating spliceosome C complex formation (By similarity). May play a role during late-stage splicing events and turnover of excised introns (By similarity). Found in the Intron Large (IL) complex, a post-mRNA release spliceosomal complex containing the excised intron, U2, U5 and U6 snRNPs, and splicing factors (By similarity). Interacts with TFIP11 and DHX15 (By similarity). Belongs to the GCF family. Was originally thought to be a DNA-binding transcriptional repressor (By similarity). However, later work showed that the original sequence was a chimera and that the DNA-binding activity was derived from the incorrect N-terminal sequence (By similarity). Truncated N-terminus.