title: Keeping the soma free of transposons: programmed DNA elimination in ciliates.
abstract: Many transposon-related sequences are removed from the somatic macronucleus of ciliates during sexual reproduction. In the ciliate Tetrahymena, an RNAi-related mechanism produces small noncoding RNAs that induce heterochromatin formation, which is followed by DNA elimination. Because RNAi-related mechanisms repress transposon activities in a variety of eukaryotes, the DNA elimination mechanism of ciliates might have evolved from these types of transposon-silencing mechanisms. Nuclear dimorphism allows ciliates to identify any DNA that has invaded the germ-line micronucleus using small RNAs and a whole genome comparison of the micronucleus and the somatic macronucleus.
authors.affiliation: Institute of Molecular Biotechnology, Austrian Academy of Sciences (IMBA), A-1030 Vienna, Austria.
authors.forename: Ursula E
authors.initials: UE
authors.lastname: Schoeberl
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Mochizuki
mesh_terms: D004251:DNA Transposable Elements / Q000502:physiology*; D016054:DNA, Protozoan / Q000378:metabolism*; D006570:Heterochromatin / Q000378:metabolism*; D048648:Macronucleus / Q000378:metabolism*; D048631:Micronucleus, Germline / Q000378:metabolism*; D013768:Tetrahymena / Q000502:physiology*
chemical_list: D004251:DNA Transposable Elements; D016054:DNA, Protozoan; D006570:Heterochromatin