title: Complete mitochondrial genome and evolutionary analysis of Turritopsis dohrnii, the "immortal" jellyfish with a reversible life-cycle.
abstract: Turritopsis dohrnii (Cnidaria, Hydrozoa, Hydroidolina, Anthoathecata) is the only known metazoan that is capable of reversing its life cycle via morph rejuvenation from the adult medusa stage to the juvenile polyp stage. Here, we present a complete mitochondrial (mt) genome sequence of T. dohrnii, which harbors genes for 13 proteins, two transfer RNAs, and two ribosomal RNAs. The T. dohrnii mt genome is characterized by typical features of species in the Hydroidolina subclass, such as a high A+T content (71.5%), reversed transcriptional orientation for the large rRNA subunit gene, and paucity of CGN codons. An incomplete complementary duplicate of the cox1 gene was found at the 5' end of the T. dohrnii mt chromosome, as were variable repeat regions flanking the chromosome. We identified species-specific variations (nad5, nad6, cob, and cox1 genes) and putative selective constraints (atp8, nad1, nad2, and nad5 genes) in the mt genes of T. dohrnii, and predicted alterations in tertiary structures of respiratory chain proteins (NADH4, NADH5, and COX1 proteins) of T. dohrnii. Based on comparative analyses of available hydrozoan mt genomes, we also determined the taxonomic relationships of T. dohrnii, recovering Filifera IV as a paraphyletic taxon, and assessed intraspecific diversity of various Hydrozoa species.
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia. Electronic address: summoner-yuna@yandex.ru.
authors.forename: A A
authors.initials: AA
authors.lastname: Lisenkova
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia; Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, 303 Belmont Street, Worcester, MA 01604, USA; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: A P
authors.initials: AP
authors.lastname: Grigorenko
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia.
authors.forename: T V
authors.initials: TV
authors.lastname: Tyazhelova
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: T V
authors.initials: TV
authors.lastname: Andreeva
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia; Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, 303 Belmont Street, Worcester, MA 01604, USA.
authors.forename: F E
authors.initials: FE
authors.lastname: Gusev
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia; Center of Genetics and Genetic Technologies, Lomonosov Moscow State University, GSP-1, Leninskie Gory, Moscow 119991, Russia.
authors.forename: A D
authors.initials: AD
authors.lastname: Manakhov
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia.
authors.forename: A Yu
authors.initials: AY
authors.lastname: Goltsov
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, I-73100 Lecce, Italy. Electronic address: stefano.piraino@unisalento.it.
authors.forename: S
authors.initials: S
authors.lastname: Piraino
authors.affiliation: Texas A&M University at Galveston, Dept. of Marine Biology, OCSB, Galveston, TX 77553, United States. Electronic address: miglietm@tamug.edu.
authors.forename: M P
authors.initials: MP
authors.lastname: Miglietta
authors.affiliation: Department of Genomics and Human Genetics, Laboratory of Evolutionary Genomics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Gubkina 3, Moscow 119991, Russia; Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, 303 Belmont Street, Worcester, MA 01604, USA; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia; Center of Genetics and Genetic Technologies, Lomonosov Moscow State University, GSP-1, Leninskie Gory, Moscow 119991, Russia. Electronic address: Evgeny.Rogaev@umassmed.edu.
authors.forename: E I
authors.initials: EI
authors.lastname: Rogaev
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004272:DNA, Mitochondrial / Q000235:genetics; D050259:Genes, Mitochondrial; D014644:Genetic Variation; D054629:Genome, Mitochondrial; D008018:Life Cycle Stages / Q000235:genetics*; D009711:Nucleotides / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D037401:Scyphozoa / Q000235:genetics* / Q000254:growth & development*
chemical_list: D004272:DNA, Mitochondrial; D009711:Nucleotides; D012335:RNA, Ribosomal
keywords: Hydrozoa; Intraspecific diversity; Linear mitochondrial DNA; Mitochondrial genome structure; Phylomitogenomics; Turritopsis dohrnii