Prions as causative agents of transmissible spongiform encephalopathies have been well investigated in experimental and modelling work. However. little is known about the molecular pathogenesis of prion-induced encephalopathies, the role of co-factors, and the interaction of prions with cellular components. We investigated the influence of prion infection on expression of murine endogenous retroviruses (ERVs), which compose approximately 10% of the mouse genome. Hypothalamic neuronal cells (GT1) and neuroblastoma cells (N2a) were examined. Both cell lines can be persistently infected with Mouse adapted prion strains, i.e., RML. Using a mammalian retrovirus-specific DNA microarray and quantitative PCR methods, we compared the expression profiles of ERVs in prion-infected, Uninfected, and anti-prion compound-treated murine neuronal cell lines, including clonal cell populations. The results suggest that prion infection influences ERV expression in neuronal cell lines, that this influence is cell line-specific, ERV-specific, and responsive to antiprion compound treatment. (c) 2006 Elsevier Inc. All rights reserved.