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Published on: December 21, 2019
Formation of nsP3-specific protein complexes during Sindbis virus replication
Elena Frolova1, Rodion Gorchakov, Natalia Garmashova
1Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-1019, USA.
Journal of Virology
|March 31, 2006
Summary
Recombinant alphaviruses revealed that the Sindbis virus nsP3 protein forms complexes with cellular proteins. These complexes, including cytoskeleton and ribosomal proteins, are essential for viral replication enzyme assembly and function.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Alphaviruses are significant arboviruses causing human and animal diseases.
- Alphavirus replication occurs in the cytoplasm, independent of the nucleus.
- Replicative complexes (RCs) involve viral and cellular proteins, assembling on organelles.
Purpose of the Study:
- To investigate the genesis and structure of alphavirus replicative enzyme complexes.
- To identify cellular proteins associated with Sindbis virus (SIN) nsP3 protein during replication.
- To understand the assembly and organization of nsP3-containing complexes.
Main Methods:
- Development of recombinant SIN viruses with GFP-tagged nsP3 protein.
- Study of nsP3/GFP complex assembly at various infection stages.
- Isolation and identification of cellular proteins interacting with nsP3/GFP.
Main Results:
- Recombinant SIN viruses with nsP3/GFP insertions are viable.
- nsP3/GFP proteins assemble into higher-order structures, evolving over infection time.
- Late-stage nsP3 complexes bind to cytoskeleton filaments and aggregate.
- Associated proteins include cytoskeleton components, chaperones, eEF1A, hnRNPs, 14-3-3, and ribosomal proteins.
Conclusions:
- SIN nsP3 protein tolerates GFP insertion, enabling structural studies.
- Cellular proteins, particularly cytoskeleton and ribosomal components, are crucial for SIN RC formation and function.
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