FOXO1 and infection: Also the expression of transcription factors is significantly modified by HHV-6A/6B infection, with an early increase of ATF3 (Cyclic AMP-dependent transcription factor), JUN and FOXA2 (Forkhead Box A2) by both species, whereas HHV-6A specifically induces a 15-fold decrease of POU2AF1 (POU Class 2 Associating Factor 1), and HHV-6B an increase of FOXO1 (Forkhead box protein O1) and a decrease of ESR1 (Estrogen Receptor 1).