Abstract:
:The symbiotic protists of the lower termite have been regarded as a model of early-branched eukaryotes because of their simple cellular systems and morphological features. However, cultivation of these symbiotic protists is very difficult. For this reason, these interesting protists have not been well characterized in terms of their molecular biology. In research on these organisms which have not yet been cultivated, we developed a method for retrieving specific genes from a small number of cells, through micromanipulation without axenic cultivation, and we obtained EF-1 alpha and alpha-tubulin genes from members of the Hypermastigida--the parabasalid protist Trichonympha agilis and the oxymonad protists Pyrsonympha grandis and Dinenympha exilis--from the termite Reticulitermes speratus gut community. Results of phylogenetic analysis of the amino acid sequences of both proteins, EF-1 alpha and alpha-tubulin, indicate that the hypermastigid, parabasalid, and oxymonad protists do not share a close common ancestor. In addition, although the EF-1 alpha phylogeny indicates that these two groups of protists branched at an early stage of eukaryotic evolution, the alpha-tubulin phylogeny indicates that these protists can be assigned to two diversified clades. As shown in a recent investigation of alpha-tubulin phylogeny, eukaryotic organisms can be divided into three classes: an animal--parabasalids clade, a plant--protists clade, and the diplomonads. In this study, we show that parabasalids, including hypermastigids, can be classified as belonging to the animal--parabasalids clade and the early-branching eukaryote oxymonads can be classified as belonging to the plant--protists clade. Our findings suggest that these protists have a cellular microtubule system that has diverged considerably, and it seems that such divergence of the microtubule system occurred in the earliest stage of eukaryotic evolution.
journal_name
J Mol Evoljournal_title
Journal of molecular evolutionauthors
Moriya S,Tanaka K,Ohkuma M,Sugano S,Kudo Tdoi
10.1007/s002390010129keywords:
subject
Has Abstractpub_date
2001-01-01 00:00:00pages
6-16issue
1eissn
0022-2844issn
1432-1432pii
10.1007/s002390010129journal_volume
52pub_type
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journal_title:Journal of molecular evolution
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journal_title:Journal of molecular evolution
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journal_title:Journal of molecular evolution
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journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/s00239-004-2624-9
更新日期:2004-08-01 00:00:00
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abstract::Adenosine 5'-phosphoramidates form when solutions containing adenosine 5'-polyphosphates pnA (n greater than or equal to 3) or P1, P2-diadenosine 5'-diphosphate and amines are allowed to dry out. Mg ions catalyze these reactions. We have studied systems containing ammonia, imidazole, glycine, ethylenediamine and hista...
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journal_title:Journal of molecular evolution
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更新日期:2011-01-01 00:00:00
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journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/BF02100629
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journal_title:Journal of molecular evolution
pub_type: 杂志文章,评审
doi:
更新日期:1999-10-01 00:00:00
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journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/s00239-004-2606-y
更新日期:2004-07-01 00:00:00
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pub_type: 杂志文章
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journal_title:Journal of molecular evolution
pub_type: 杂志文章
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abstract::Twenty-one different caprine and 13 ovine MHC-DRB exon 2 sequences were determined including part of the adjacent introns containing simple repetitive (gt)n(ga)m elements. The positions for highly polymorphic DRB amino acids vary slightly among ungulates and other mammals. From man and mouse to ungulates the basic (gt...
journal_title:Journal of molecular evolution
pub_type: 杂志文章
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更新日期:1993-09-01 00:00:00
abstract::The entire mitochondrial DNA control region (mtDNA D-loop) was sequenced in the seven extant species of Alectoris partridges. The D-loop length is very conserved (1155 +/- 2 nucleotides), and substitution rates are lower than for the mitochondrial cytochrome b gene of the same species, on average. Comparative analyses...
journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/pl00006402
更新日期:1998-10-01 00:00:00
abstract::The organization of histone gene clusters of the duck Cairina moschata was studied in the DNA inserts of two recombinant phage that overlap and feature identical histone gene arrangements but differ in sequence details and in the extent of repetition of an AT-rich motif in one of the nontranscribed spacer regions. The...
journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/BF02102477
更新日期:1989-03-01 00:00:00
abstract::Several algae that were previously classified in the phylum Xanthophyta (yellow-green algae) were assigned in 1971 to a new phylum, Eustigmatophyta. It was anticipated that the number of algae reclassified to Eustigmatophyta would increase. However, due to the fact that the morphological characteristics that segregate...
journal_title:Journal of molecular evolution
pub_type: 杂志文章
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更新日期:1997-08-01 00:00:00
abstract::The phylogeny of the creatine kinase (CK, EC 2.7.3.2) isozyme loci and their differential tissue expressions were determined for representatives of 65 families of vertebrates, with emphasis on the fishes. The transition from the single creatine kinase locus, characteristic of certain echinoderms, to the two creatine k...
journal_title:Journal of molecular evolution
pub_type: 杂志文章
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journal_title:Journal of molecular evolution
pub_type: 杂志文章
doi:10.1007/BF02101892
更新日期:1990-04-01 00:00:00
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pub_type: 杂志文章
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