Irreversible inhibition is different from irreversible enzyme inactivation. Another mode of inactivation is overproduction inhibition. The detection of p16 inactivation in familial melanoma supplied further evidence. Scaffolds have been proposed to protect activated signaling molecules from inactivation and/or degradation. Common sites for gene inactivation include H3K9 and H3K27. PEV is a "heterochromatin-induced gene inactivation". More specifically, pyrin detects inactivation of the Rho GTPase RHOA by these bacterial factors. A fraction of the genes along the X chromosome escape inactivation on the Xi. Bradykinin increases because of less inactivation by ACE. The inactive X chromosome is coated with this transcript, which is essential for the inactivation. X chromosomes in females undergo a process known as X inactivation. Another classic example is X chromosome inactivation by XIST. The time period for X-chromosome inactivation explains this disparity. Ultimately, this leads to the inactivation of transcription. The venom reduces the rate and amount of sodium inactivation.