ATF1 and infection: One transcription factor that was predicted to bind to the HCLS1 promoter was ATF1, and this particularly came to our attention because it is known to be upregulated by Src signaling, a signaling pathway known to be involved in infection of monocytes by HCMV (Nogalski et al., 2011) (Shi et al., 2011) (Hokari et al., 2005).