Export of messenger RNA (mRNA) from the nucleus to the cytoplasm is a critical step in the gene expression pathway of eukaryotic cells. In mammals, the TREX-2 complex links transcription/processing with nuclear mRNA export. Mammalian TREX-2 is based on a germinal-centre associated nuclear protein (GANP) scaffold to which ENY2, PCID2 and centrins bind PMID:22307388. ENY2 is a small transcription factor which is conserved from protozoa to humans PMID:11438676. In insects it is known as the enhancer of yellow 2 transcription factor (EnY2), but in other organisms is known as transcription and mRNA export factor SUS1 or ENY2. It is involved in mRNA export coupled transcription activation by association with both the TREX-2 complex and the transcription regulatory histone acetylation complex SAGA PMID:14718168,PMID:21746879,PMID:18923079,PMID:18034162. This entry represents ENY2 which is made up of 5 alpha-helices separated by hinge regions, arranged into an anti-parallel hairpin PMID:22307388.