Previous global analyses of T4 gene expression using hybridization studies or levels of various phage proteins during a T4motAam infection have indicated that when MotA-dependent promoters are not activated, expression of some early genes remains high, while late transcription, which is dependent on the middle products gp55, gp33, and gp45, is significantly diminished (reviewed in [54]). This evidence concerns the gene NPTN and infection.