PPARG and cytomegalovirus infection: Although the impacts of virus infection on neural progenitor cell proliferation, differentiation, and migration have been described, several reports have outlined the impact of virus infection on the expression of cellular genes that have also been associated with the decreased neurogenesis, differentiation and migration of neural stem cells, including the finding that HCMV infection increased expression of the transcription factor peroxisome proliferator-activated receptor gamma (PPARγ) in neighboring but uninfected cells [25,26].