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Analysis of mRNA Nuclear Export Kinetics in Mammalian Cells by Microinjection
Published on: December 4, 2010
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Influenza virus mRNAs encode determinants for nuclear export via the cellular TREX-2 complex.
Prasanna Bhat1, Vasilisa Aksenova2, Matthew Gazzara3
1Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
Nature Communications
|April 21, 2023
Summary
Influenza A virus (IAV) mRNA export relies on the nucleoporin TPR and the TREX-2 complex, which is essential for viral replication. Specific RNA sequences in IAV HA mRNA mediate this export.
Area of Science:
- Molecular Biology
- Virology
- Cell Biology
Background:
- Nuclear export of messenger RNAs (mRNAs) is crucial for gene expression.
- Influenza A virus (IAV) replication depends on efficient nuclear export of its mRNAs through the nuclear pore complex (NPC).
Purpose of the Study:
- To identify key nucleoporins and cellular factors involved in IAV mRNA nuclear export.
- To elucidate the role of the TRanscription and EXport complex-2 (TREX-2) in IAV mRNA export and replication.
Main Methods:
- Utilized the Auxin-Induced Degron (AID) system for rapid protein degradation.
- Investigated the function of nucleoporin TPR and TREX-2 complex components (GANP, PCID2) in IAV mRNA export.
- Analyzed characteristics of cellular mRNAs exported by GANP and identified RNA signals in IAV HA mRNA.
Main Results:
- TPR was identified as a key nucleoporin for IAV mRNA nuclear export.
- The TREX-2 complex, including GANP and PCID2, is required for IAV mRNA nuclear export and replication.
- Specific features of cellular mRNAs exported by GANP were identified, some shared with IAV mRNAs.
- A 45-nucleotide RNA signal in IAV HA mRNA was found to mediate GANP-dependent export.
Conclusions:
- The TREX-2 complex plays a significant role in the nuclear export of influenza A virus mRNAs.
- RNA sequence elements within viral mRNAs contribute to their nuclear export pathway via cellular machinery.
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