Related Experiment Videos
Defective translation of measles virus matrix protein in a subacute sclerosing panencephalitis cell line
Abstract:
Subacute sclerosing panencephalitis (SSPE) is a slowly progressing fatal human disease of the central nervous system (CNS) that is associated with measles virus persistence. Virus nucleocapsids are present in the brain and the patient is in a state of hyperimmunization towards this agent. However, although all other structural polypeptides are recognized by the immune system, there is a markedly decreased antibody response towards virus matrix or membrane protein. Matrix protein has not been detected in brain cells and infectious virus is not present. The absence of this virus structural polypeptide is thought to account for the apparent restriction in virus maturation both in vivo and in vitro. SSPE viruses can only rarely be rescued from brain tissue by co-cultivation or cell fusion techniques using tissue culture cell lines susceptible to measles virus infection. Often this procedure fails to yield a lytic budding virus but produces instead a carrier cell line in which the agent is cell associated. These lines (known as SSPE cell lines) also do not contain matrix protein. However, the reason for this deficiency is unknown. We have therefore now examined an SSPE cell line which does not yield infectious virus in order to define this process further. We found that although messenger RNA for membrane protein was present, it was unable to form normal matrix protein in translation reactions.
Insights
Subacute sclerosing panencephalitis (SSPE) involves persistent measles virus. SSPE cell lines lack matrix protein due to translation issues, hindering infectious virus production.
Area of Science:
- Neurology
- Virology
- Immunology
Background:
- Subacute sclerosing panencephalitis (SSPE) is a fatal neurological disease linked to persistent measles virus.
- Patients exhibit hyperimmunity but have a reduced antibody response to measles virus matrix/membrane proteins.
- Matrix protein absence is hypothesized to restrict measles virus maturation in SSPE.
Purpose of the Study:
- To investigate the molecular basis for the deficiency of matrix protein in an SSPE cell line that does not produce infectious virus.
- To further define the process of restricted virus maturation in SSPE.
Main Methods:
- Analysis of an SSPE cell line lacking infectious virus production.
- Examination of messenger RNA (mRNA) for membrane protein and subsequent translation reactions.
Main Results:
- Messenger RNA for membrane protein was detected in the SSPE cell line.
- Despite mRNA presence, normal matrix protein formation failed during translation reactions.
- Infectious virus and detectable matrix protein were absent in the studied SSPE cell line.
Conclusions:
- The inability to form normal matrix protein, despite the presence of its mRNA, is a key factor in the lack of infectious virus production in this SSPE cell line.
- This translational defect contributes to the restricted measles virus maturation observed in subacute sclerosing panencephalitis.