The effects of measles virus persistent infection on AP-1 transcription factor binding in neuroblastoma cells

Measles virus (MV) persistence in brain cells has broad effects on different cellular functions. We have previously shown that NS20Y clone, originally derived from C1300 neuroblastoma cells, persistently infected with MV (NS20Y/MS), displays constitutively elevated levels of c-fos and PKC mRNAs, implying MV-mediated effects on transcriptional regulation. Nonetheless, the mode by which virus affects the transcriptional machinery still remains obscure. In order to define this phenomenon, we studied the binding properties of major transcription factors (AP-1 and NFκB) in NS20Y/MS cells. Using electrophoretic mobility shift approach (EMSA) with the appropriate oligonucleotide probes, we have found that the persistent MV infection does not affect NFκB binding, while the AP-1 binding was significantly decreased. Similar inhibition was not observed in NS20Y cells acutely infected with MV. Anti-measles antibody-mediated restriction of viral gene expression restored AP-1 binding, thus suggesting that measles virus proteins may affect the components of the host transcriptional machinery.