Regulation of mRNA export by the PI3 kinase/AKT signal transduction pathway.

ABSTRACT: UAP56, ALY/REF, and NXF1 are mRNA export factors that sequentially bind at the 5' end of a nuclear mRNA but are also reported to associate with the exon junction complex (EJC). To screen for signal transduction pathways regulating mRNA export complex assembly, we used fluorescence recovery after photobleaching to measure the binding of mRNA export and EJC core proteins in nuclear complexes. The fraction of UAP56, ALY/REF, and NXF1 tightly bound in complexes was reduced by drug inhibition of the phosphatidylinositide 3-kinase (PI3 kinase)/AKT pathway, as was the tightly bound fraction of the core EJC proteins eIF4A3, MAGOH, and Y14. Inhibition of the mTOR mTORC1 pathway decreased the tight binding of MAGOH. Inhibition of the PI3 kinase/AKT pathway increased the export of poly(A) RNA and of

SUBMITTER: Quaresma AJ 

PROVIDER: S-EPMC3623641 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature