TREX exposes the RnA-binding domain of nxf1to enable mRnA export

摘要

The metazoan TREX complex is recruited to mRnA during nuclear RnA processing and functionsin exporting mRnA to the cytoplasm. nxf1 is an mRnA export receptor, which binds processedmRnA and transports it through the nuclear pore complex. At present, the relationship betweenTREX and nxf1 is not understood. Here we show that nxf1 uses an intramolecular interaction toinhibit its own RnA-binding activity. When the TREX subunits Aly and Thoc5 make contact withnxf1, nxf1 is driven into an open conformation, exposing its RnA-binding domain, allowing RnAbinding. moreover, the combined knockdown of Aly and Thoc5 markedly reduces the amountof nxf1 bound to mRnA in vivo and also causes a severe mRnA export block. Together, our dataindicate that TREX provides a license for mRnA export by driving nxf1 into a conformationcapable of binding mRnA.