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Infectious Bronchitis Virus Nonstructural Protein 4 Alone Induces Membrane Pairing.
Nicole Doyle1, Benjamin W Neuman2, Jennifer Simpson3
1The Pirbright Institute, Pirbright, Surrey GU24 0NF, UK. nicole.doyle@pirbright.ac.uk.
Viruses
|September 12, 2018
Summary
Infectious bronchitis virus (IBV) non-structural protein 4 (nsp4) alone induces membrane pairing, a key step in coronavirus replication. However, other viral or host factors are needed for full replication organelle formation.
Area of Science:
- Virology
- Cell Biology
- Molecular Biology
Background:
- Positive-strand RNA viruses, including coronaviruses, remodel host cell membranes to create replication organelles for efficient RNA synthesis.
- Infectious bronchitis virus (IBV), an avian gammacoronavirus, induces double membrane vesicles (DMVs), zippered endoplasmic reticulum (zER), and spherules.
Purpose of the Study:
- To identify the specific viral non-structural proteins (nsps) responsible for inducing membrane rearrangements during IBV replication.
- To compare membrane rearrangement induction by nsps from different IBV strains.
Main Methods:
- Expression of IBV non-structural transmembrane proteins (nsp3, nsp4, nsp6) individually and in combination in cells.
- Investigation of cellular membrane effects using electron microscopy and electron tomography.
Main Results:
- IBV nsp4 alone was found to be necessary and sufficient for inducing membrane pairing, a distinct finding compared to other coronaviruses.
- Co-expression of nsp3, nsp4, and nsp6 did not fully recapitulate the formation of double membrane vesicles (DMVs).
Conclusions:
- IBV nsp4 plays a crucial role in initiating membrane rearrangements by inducing membrane pairing.
- Full assembly of IBV replication structures requires additional viral or host factors beyond nsp3, nsp4, and nsp6.
Keywords:
coronaviruselectron tomographyinfectious bronchitis virusmembrane rearrangementsnon-structural proteinnsp3nsp4paired membraneszippered ERMore Related Videos
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