Probably functions as scaffold protein that is part of numerous complexes and thereby plays a role in pre-mRNA splicing, transcription regulation and neuron development. Required for normal alternative splicing of target pre-mRNA species (PubMed:23512658). May suppress the ability of POU3F2 to transactivate the DRD1 gene in a POU3F2 dependent manner. Can activate transcription directly or via association with the transcription machinery. May be involved in ATXN1 mutant-induced cell death. The interaction with ATXN1 mutant reduces levels of phosphorylated RNA polymerase II large subunit.