TNRC4, also named as BRUNOL1, CAGH4, ERDA4, or TNRC4, is a 465 amino acid protein, which contains three RRM (RNA recognition motif) domains and belongs to the CELF/BRUNOL family. TNRC4 localizes in the nucleus and is expressed in brain. TNRC4 as a RNA-binding protein is involved in the regulation of pre-mRNA alternative splicing and mediates exon inclusion and/or exclusion in pre-mRNA that are subject to tissue-specific and developmentally regulated alternative splicing.