Viral infection leads to generation of novel cell states. (A) Simplified scheme of the epigenetic landscape. The gene regulatory network that operates in pluripotent cells (open circle) yields the stable and distinct (attractor) states of network that define the specific cell types. The attractor occupies the low-energy stable basin, and providing robustness against perturbations. The y axis represents the relative stability of individual cell states where higher positions indicate less stability. The valleys represent stable attractor states. (B and C) Gene regulatory networks (B) generate stable differentiated cell phenotypes (red) as well as innate antiviral states (blue) of differentiated cells (C). The latter is defined by expression levels of various antiviral proteins in the absence of detectable viral infection. Progression of viral infection is associated with virus-mediated suppression of the antiviral state, characterized by expression of type I IFN and ISGs, and establishment of the proviral state (yellow) that supports viral replication. Generation and stability of antiviral or proviral attractors may determine the outcome of the viral infection.