sentences:  Under normal conditions, type I IFN levels are homeostatically regulated to balance the benefits of protection from viral infection with the other cellular effects associated with type I IFN signaling, such as apoptosis, cell cycle arrest, and immune modulation.The stringent regulation of type I IFN signaling suggests the importance of timing and location.Type I IFN signaling is controlled through various mechanisms, including differential expression of signaling components, differential signaling following IFNAR engagement, endocytosis and downregulation of the receptors.