Related Experiment Videos
Events following the infections of enucleate cells with measles virus
Abstract:
The development of measles virus (Edmonston) and SSPE measles virus (Horta-Barbosa) has been examined in enucleate BSC 1 cells. New antigen synthesis in measles virus infected enucleate cells has been demonstrated by fluorescent antibody, by the formation of extensive syncytia from enucleate cells alone and by analysis of polypeptide formation by polyacrylamide gel electrophoresis. All polypeptides formed in nucleate cells were also present in enucleate cells but the amount synthesized was reduced to around 20% of that in nucleate cells. There was also a significant reduction in the amount of antigen detected by fluorescent antibody in enucleate as compared to nucleate preparations. Examination of RNA synthesis in infected enucleate cells revealed only a marginal increase in acid-insoluble material. Titration of the output of infectious virus from enucleate cells infected at both 37 and 31 degrees C indicated a consistent reduction of almost two log units compared to nucleate cells. That the enucleate cells were capable of replicating input genome at these times was demonstrated by the successful growth of respiratory syncytial virus, both at 37 and 31 degrees C. SSPE measles virus grew to higher yield in nucleate BSC 1 than measles virus but there was again a reduction of more than two log units in enucleate cells. All polypeptides synthesized in SSPE infected nucleate cells were apparent in enucleate cells.
Insights
Measles virus (Edmonston) and SSPE measles virus replicate in enucleate cells, but at significantly reduced levels. This indicates the nucleus is crucial for efficient viral replication and antigen synthesis.
Area of Science:
- Virology
- Cell Biology
Background:
- Measles virus (Edmonston) and Subacute sclerosing panencephalitis (SSPE) measles virus are significant human pathogens.
- Understanding viral replication mechanisms is crucial for developing effective antiviral strategies.
- The role of the host cell nucleus in viral development is not fully elucidated for all viruses.
Purpose of the Study:
- To investigate the replication and antigen synthesis of measles virus and SSPE measles virus in enucleate cells.
- To determine the necessity of the cell nucleus for efficient viral genome replication and protein production.
Main Methods:
- Infection of enucleate BSC 1 cells with measles virus (Edmonston) and SSPE measles virus (Horta-Barbosa).
- Detection of new antigen synthesis using fluorescent antibody techniques.
- Analysis of polypeptide formation via polyacrylamide gel electrophoresis.
- Assessment of viral RNA synthesis and infectious virus output.
Main Results:
- Measles virus and SSPE measles virus synthesized viral polypeptides and new antigens in enucleate cells, albeit at reduced levels (approx. 20%).
- Viral RNA synthesis showed only a marginal increase in enucleate cells.
- Infectious virus output was reduced by nearly two log units in enucleate cells compared to nucleate cells for both viral strains.
Conclusions:
- Enucleate cells can support measles virus and SSPE measles virus replication, demonstrating that the nucleus is not absolutely essential for all stages of the viral life cycle.
- The host cell nucleus plays a critical role in enhancing the efficiency of viral replication, antigen synthesis, and infectious virus production.
- These findings highlight the importance of nuclear functions in optimizing viral development.