Meta-Biol

• Pathways

The THO subcomplex of the TREX complex initially interacts with the serine-2,5 phosphorylated C-terminal domain of RNA polymerase II (Strasser et al. 2002, Inferred from yeast in Meinel et al. 2013) then with CBP80 of the cap binding complex (Cheng et al. 2006, Dufu et al. 2010, Chi et al. 2013). A TREX complex binds spliced mRNA near the cap during transcription (Cheng et al. 2006). Recruitment is dependent on splicing of the mRNA (Masuda et al. 2005). THO/TREX is required for efficient mRNP biogenesis and export (reviewed in Luna et al 2012). In yeast, components of the THO/TREX complex also affect transcription and 3' processing of mRNA, (Rondon et al. 2003, Rougemaille et al. 2008, Johnson et al. 2011, reviewed in Katahira 2015), however the human TREX complex does not appear to affect transcription (Masuda et al. 2005). The AREX complex, which contains DDX39A (UHR49) rather than DDX39B (UAP56) appears to perform the same function as TREX in mRNA export, but acts on a different subset of mRNAs (Yamazaki et al. 2010).