Positive Regulation Genes - N and Q are positive regulation genes whose products increase the rate of transcription of other genes. The product of the N gene stimulates transcription of genes cII, 0, p, Q, gam, exo, bet, xis and int. The product of the Q gene increases transcription of the head, tail and lysis genes. Plaque formation requires both N and Q genes.
In the absence of these genes the number of phage particles produced is small but not zero.
