Partner of Y14 and Mago (WIBG) is a key regulator of the Exon Junction Complex (EJC). EJC is a multiprotein complex that associates immediately upstream of the exon-exon junction on mRNAs, is a positional landmarker for the intron exon structure of genes, and directs post-transcriptional processes in the cytoplasm, for instance mRNA export, nonsense-mediated mRNA decay or translation. WIBG is a cytoplasmic RNA-binding protein, it can be excluded from nucleus by Crm1. WIBG as a cooperateing partner of Mago-14, relates with Mago-14 by its N-terminal domain.