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Updated: Jul 6, 2026
07:10
A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
NFAR-1 and -2 modulate translation and are required for efficient host defense
Ingrid Pfeifer1, Rachel Elsby, Marilyn Fernandez
1Department of Medicine and Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
Summary
Nuclear factors associated with double-stranded RNA (NFARs) retain cellular transcripts and regulate mRNA export. Loss of NFAR function increases protein synthesis and susceptibility to viral replication, suggesting a role in innate immunity.
Area of Science:
- Molecular Biology
- Virology
- Cell Biology
Background:
- Nuclear factors associated with double-stranded RNA (NFAR-1 and NFAR-2) are involved in RNA processing.
- The precise roles of NFAR proteins in mRNA export and cellular defense are not fully understood.
Purpose of the Study:
- To investigate the function of NFAR proteins in mRNA trafficking and protein synthesis.
- To determine the role of NFARs in host defense against viral infections.
Main Methods:
- Studied the localization and function of NFAR proteins in cellular transcripts.
- Assessed the impact of NFAR loss of function on protein synthesis rates.
- Examined the susceptibility of NFAR-depleted cells to vesicular stomatitis virus (VSV) replication.
Main Results:
- NFAR proteins retain cellular transcripts in intranuclear foci and regulate mRNA export.
- Loss of NFAR function led to increased protein synthesis rates, exacerbated by mRNA export factors.
- NFAR depletion rendered murine fibroblasts highly susceptible to VSV replication.
Conclusions:
- NFARs play a critical role in mRNA trafficking and translation modulation.
- NFARs may function as an innate immune translational surveillance mechanism.
- NFARs are essential for host defense against viral infections.
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