A Sub-Element in PRE enhances nuclear export of intronless mRNAs by recruiting the TREX complex via ZC3H18.
Bottom Line: We found that PRE drastically enhances the cytoplasmic accumulation of cDNA transcripts independent of any viral protein.Consistent with these similarities, several SEP1-interacting proteins, including ZC3H18, ARS2, Acinus and Brr2, are required for efficient nuclear export of polyA RNAs.Together, our data indicate that SEP1 enhances mRNA export by recruiting TREX via ZC3H18.
Affiliation: Shanghai Key Laboratory of Molecular Andrology, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.Show MeSH
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Mentions: The fact that TREX specifically associates with the SEP1 RNA raised the possibility that it plays a role in SEP1-dependent mRNA export. To test this possibility, we carried out RNA-mediated interference (RNAi) of UAP56/URH49, Aly and Thoc2 in HeLa cells and used a nontargeting siRNA as a negative control. Western analyses revealed that protein levels of these genes were efficiently knocked down (Figure 3A). When the cG-SEP1 construct was transfected into control knockdown cells, the corresponding mRNA was mainly detected in the cytoplasm. In marked contrast, the cG-SEP1 mRNA was mostly retained in the nuclei in UAP56/URH49-, Aly- and Thoc2-knockdown cells (Figure 3B). These results indicate that TREX plays key roles in SEP1-mediated mRNA export.
Affiliation: Shanghai Key Laboratory of Molecular Andrology, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.