title: The telomere repeat motif of basal Metazoa.
abstract: In most eukaryotes the telomeres consist of short DNA tandem repeats and associated proteins. Telomeric repeats are added to the chromosome ends by telomerase, a specialized reverse transcriptase. We examined telomerase activity and telomere repeat sequences in representatives of basal metazoan groups. Our results show that the 'vertebrate' telomere motif (TTAGGG)( n ) is present in all basal metazoan groups, i.e. sponges, Cnidaria, Ctenophora, and Placozoa, and also in the unicellular metazoan sister group, the Choanozoa. Thus it can be considered the ancestral telomere repeat motif of Metazoa. It has been conserved from the metazoan radiation in most animal phylogenetic lineages, and replaced by other motifs-according to our present knowledge-only in two major lineages, Arthropoda and Nematoda.
authors: Institut für Biologie, Zentrum für Medizinische Struktur- und Zellbiologie, Universität zu Lübeck, D-23538, Lübeck, Germany. traut@molbio.uni-luebeck.de
authors: Walther
authors: W
authors: Traut
authors: Monika
authors: M
authors: Szczepanowski
authors: Magda
authors: M
authors: Vítková
authors: Christian
authors: C
authors: Opitz
authors: Frantisek
authors: F
authors: Marec
authors: Jan
authors: J
authors: Zrzavý
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D003063:Cnidaria; D017124:Conserved Sequence; D037302:Ctenophora; D007448:Invertebrates / Q000235:genetics*; D018895:Microsatellite Repeats; D010802:Phylogeny; D011161:Porifera; D019098:Telomerase; D016615:Telomere / Q000737:chemistry* / Q000235:genetics
chemical_list: D019098:Telomerase