Related Experiment Videos
Molecular biology of the pathogenesis of Sendai viruses
1Department of Microbiology, California State University, Los Angeles 90032-8205.
Abstract:
Protease activation mutant (ts-f1) was isolated from persistently infected cells, and a pantropic mutant, F1-R, was derived from ts-f1. The mutants have been found to be extremely useful for investigations on the molecular biology of paramyxoviruses. The genome of the mutants has been sequenced and mutations were revealed in several proteins encoded by the genes. Three of the six mutations in the fusion (F) proteins were considered prime candidates for the determinants of pantropism. Characterization of the revertants, that are no longer pantropic and derived from F1-R, revealed that the mutation at amino acid residue (115 Arg to Pro) of the F protein is responsible for pantropism. Another important finding was bipolar budding of F1-R in polarized epithelial cells and mouse bronchial epithelium. It has been postulated that mutation(s) in the matrix (M) protein may be associated with bipolar budding since the revertants retained this phenotype of F1-R.
Insights
A specific mutation in the fusion (F) protein of paramyxoviruses determines pantropism. This finding aids in understanding paramyxovirus molecular biology and potential therapeutic targets.
Area of Science:
- Virology
- Molecular Biology
Background:
- Paramyxoviruses are significant human and animal pathogens.
- Understanding paramyxovirus tropism is crucial for disease control.
- Mutants are valuable tools for studying paramyxovirus molecular biology.
Purpose of the Study:
- To identify the genetic determinants of paramyxovirus pantropism.
- To investigate the molecular basis of bipolar budding in paramyxoviruses.
Main Methods:
- Isolation and characterization of paramyxovirus mutants (ts-f1, F1-R) and their revertants.
- Genome sequencing of paramyxovirus mutants.
- Analysis of mutations in fusion (F) and matrix (M) proteins.
Main Results:
- A mutation at amino acid residue 115 (Arg to Pro) in the F protein was identified as the determinant of pantropism.
- Bipolar budding was observed in F1-R mutant in polarized epithelial cells and mouse bronchial epithelium.
- Revertants retained the bipolar budding phenotype, suggesting M protein involvement.
Conclusions:
- The F protein residue 115 is critical for paramyxovirus pantropism.
- The M protein may play a role in the bipolar budding phenotype observed in paramyxoviruses.
- These findings advance the understanding of paramyxovirus pathogenesis and host range.