THO complex subunit 1 (THOC1)

Required for efficient export of polyadenylated RNA. Acts as component of the THO subcomplex of the TREX complex that's believed to couple mRNA transcription, processing and nuclear export, and which specifically associates with spliced mRNA and not with unspliced pre-mRNA.

TREX is recruited to spliced mRNAs with a transcription-independent mechanism, binds to mRNA upstream of the exon-junction complex (EJC) and can be recruited in a splicing- and cap-dependent way to a region near the 5' end of the mRNA where it functions in mRNA export to the cytoplasm through the TAP/NFX1 pathway. The TREX complex is essential for the export of Kaposi's sarcoma-associated herpesvirus (KSHV) intronless mRNAs and infectious virus production.