title: Early evolutionary origin of the planktic foraminifera inferred from small subunit rDNA sequence comparisons.
abstract: Phylogenetic analysis of five partial planktic foraminiferal small subunit (SSU) ribosomal (r) DNA sequences with representatives of a diverse range of eukaryote, archaebacterial, and eubacterial taxa has revealed that the evolutionary origin of the foraminiferal lineage precedes the rapid eukaryote diversification represented by the "crown" of the eukaryotic tree and probably represents one of the earliest splits among extant free-living aerobic eukaryotes. The foraminiferal rDNA sequences could be clearly separated from known symbionts, commensals, and food organisms. All five species formed a single monophyletic group distinguished from the "crown" group by unique foraminiferal specific insertions as well as considerable nucleotide distance in aligned regions.
authors.affiliation: Centre for HIV Research, Institute of Cell, Animal and Population Biology, University of Edinburgh, UK.
authors.forename: C M
authors.initials: CM
authors.lastname: Wade
authors.forename: K F
authors.initials: KF
authors.lastname: Darling
authors.forename: D
authors.initials: D
authors.lastname: Kroon
authors.forename: A J
authors.initials: AJ
authors.lastname: Leigh Brown
mesh_terms: D000818:Animals; D005075:Biological Evolution; D017931:DNA Primers; D016054:DNA, Protozoan / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics*; D016828:Diplomonadida / Q000145:classification / Q000502:physiology; D056890:Eukaryota / Q000145:classification / Q000235:genetics* / Q000502:physiology; D005057:Eukaryotic Cells; D016830:Kinetoplastida / Q000145:classification / Q000502:physiology; D008954:Models, Biological; D010802:Phylogeny; D010933:Plankton / Q000145:classification / Q000502:physiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012689:Sequence Homology, Nucleic Acid
chemical_list: D017931:DNA Primers; D016054:DNA, Protozoan; D004275:DNA, Ribosomal