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Functional comparison of PML-type and archetype strains of JC virus

E Sock1, K Renner, D Feist

  • 1Zentrum für Molekulare Neurobiologie, Universität Hamburg, Germany.

Journal of Virology
|March 1, 1996
PubMed

Insights

Differences in regulatory regions do not explain why PML-type JC polyomaviruses cause progressive multifocal leukoencephalopathy, while archetype strains do not. Both viral types show glial cell preference for gene expression.

Area of Science:

  • Virology
  • Molecular Biology
  • Neuroscience

Background:

  • Human polyomavirus JC (JCPyV) strains are classified as PML-type or archetype based on regulatory region differences.
  • PML-type JCPyV is associated with progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease.
  • Archetype JCPyV strains are typically found in healthy individuals.

Purpose of the Study:

  • To compare the functional properties of archetype and PML-type JCPyV regulatory regions.
  • To investigate differences in DNA replication and viral gene expression.
  • To determine if regulatory region variations account for the distinct pathobiology of JCPyV strains.

Main Methods:

  • Functional analysis of viral DNA replication using JC virus T antigen.
  • Assessment of early- and late-gene promoter activity in glial and non-glial cells.
  • Investigation of promoter response to viral T antigen and glial transcription factor Tst-1/Oct6.

Main Results:

  • No significant differences in episomal DNA replication directed by archetype and PML-type regulatory regions.
  • Both PML-type and archetype JCPyV promoters showed preferential activity in glial cells, with a stronger effect for PML-type.
  • Archetype strain promoters responded similarly to T antigen and Tst-1/Oct6 as PML-type strain Mad-1 promoters.

Conclusions:

  • Differences in regulatory regions do not fully explain the distinct biological behavior of archetype and PML-type JCPyV strains.
  • Both JCPyV strain types exhibit glial cell-specific gene expression.
  • T antigen and Tst-1/Oct6 exhibit species-specific and cell-type-specific functions, respectively.

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