A protein, possibly even a new organelle, found in the one-celled ciliated protozoan "tetrahymena," an organism which contains two nuclei (unlike most other organisms which only contain one) - the macronucleus and the micronucleus. During sexual reproduction, in which two tetrahymena fuse and produce four offspring, this protein destroys the two parental macronuclei (whose genetic material were not used during the sexual reproduction) and removes the genes related to sexual reproduction from all offspring macronuclei.