Tho4 is an alias for the gene, Aly/REF export factor, in humans. Other names include: THO complex subunit 4; Tho4; Ally of AML-1 and LEF-1; Transcriptional coactivator Aly/REF; bZIP-enhancing factor BEF; ALY; ALY/REF; BEF; REF; THOC4. The encoded protein has an amino acid length of 257 and a mass of 26.9 kDa. Other isoforms may exist. Tho4 is a member of the ALYREF family. This gene shares homology with other species, including: Fly, Mouse, Frog.