1. Antiterminator protein of the bacteriophage _ and other phages that plays a key role in the early stages of infection. During the early phase, only two genes N and cro are transcribed, by transcription of the DNA in opposite directions. N protein binds to sites on the DNA (nut sites for N utilisation), prevents rho dependent termination and allows transcription of the genes.
2. Name was once used for GTP-binding proteins G-proteins), now obsolete and should be avoided because of confusion with N protein of bacteriophages.
(18 Nov 1997)