title: Phylogenetic position of Multicilia marina and the evolution of Amoebozoa.
abstract: Recent molecular phylogenetic studies have led to the erection of the phylum Amoebozoa, uniting naked and testate lobose amoebae, the mycetozoan slime moulds and amitochondriate amoeboid protists (Archamoebae). Molecular data together with ultrastructural evidence have suggested a close relationship between Mycetozoa and Archamoebae, classified together in the Conosea, which was named after the cone of microtubules that, when present, is characteristic of their kinetids. However, the relationships of conoseans to other amoebozoans remain unclear. Here, we obtained the complete small-subunit (SSU) rRNA gene sequence (2746 bp) of the enigmatic, multiflagellated protist Multicilia marina, which has formerly been classified either in a distinct phylum, Multiflagellata, or among lobose amoebae. Our study clearly shows that Multicilia marina belongs to the Amoebozoa. Phylogenetic analyses including 60 amoebozoan SSU rRNA gene sequences revealed that Multicilia marina branches at the base of the Conosea, together with another flagellated amoebozoan, Phalansterium solitarium, as well as with Gephyramoeba sp., Filamoeba nolandi and two unidentified amoebae. This is the first report showing strong support for a clade containing all flagellated amoebozoans and we discuss the position of the root of the phylum Amoebozoa in the light of this result.
authors.affiliation: Department of Evolutionary Biochemistry, A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia.|Department of Zoology and Animal Biology, University of Geneva, Geneva, Switzerland.
authors.forename: Sergey I
authors.initials: SI
authors.lastname: Nikolaev
authors.affiliation: Department of Zoology and Animal Biology, University of Geneva, Geneva, Switzerland.
authors.forename: Cédric
authors.initials: C
authors.lastname: Berney
authors.affiliation: Department of Evolutionary Biochemistry, A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia.
authors.forename: Nikolai B
authors.initials: NB
authors.lastname: Petrov
authors.affiliation: Institute of Biology of Inland Waters, Russian Academy of Sciences, Yaroslavskaya obl., Borok, Russia.
authors.forename: Alexandre P
authors.initials: AP
authors.lastname: Mylnikov
authors.affiliation: Department of Zoology and Animal Biology, University of Geneva, Geneva, Switzerland.
authors.forename: José F
authors.initials: JF
authors.lastname: Fahrni
authors.affiliation: Department of Zoology and Animal Biology, University of Geneva, Geneva, Switzerland.
authors.forename: Jan
authors.initials: J
authors.lastname: Pawlowski
mesh_terms: D000656:Amoeba / Q000145:classification* / Q000235:genetics / Q000254:growth & development; D000818:Animals; D003001:Cloning, Molecular; D016054:DNA, Protozoan / Q000235:genetics / Q000302:isolation & purification; D004141:Dinoflagellida / Q000145:classification / Q000235:genetics; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D016053:RNA, Protozoan / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics
chemical_list: D016054:DNA, Protozoan; D016053:RNA, Protozoan; D012335:RNA, Ribosomal