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High Bootstrap Values (high + bootstrap_value)
Selected AbstractsPhylogeny and speciation of the eastern Asian cyprinid genus SarcocheilichthysJOURNAL OF FISH BIOLOGY, Issue 5 2008L. Zhang The genus Sarcocheilichthys is a group of small cyprinid fishes comprising 10 species/sub-species widely distributed in East Asia, which represents a valuable model for understanding the speciation of freshwater fishes in East Asia. In the present study, the molecular phylogenetic relationship of the genus Sarcocheilichthys was investigated using a 1140 bp section of the mitochondrial cytochrome b gene. Two different tree-building methods, maximum parsimony (MP) and Bayesian methods, yielded trees with almost the same topology, yielding high bootstrap values or posterior probabilities. The results showed that the genus Sarcocheilichthys consists of two large clades, clades I and II. Clade I contains Sarcocheilichthys lacustris, Sarcocheilichthys sinensis and Sarcocheilichthys parvus, with S. parvus at a basal position. In clade II, Sarcocheilichthys variegatus microoculus is at a basal position; samples of the widespread species, Sarcocheilichthys nigripinnis, form a large subclade containing another valid species Sarcocheilichthys czerskii. Sarcocheilichthys kiangsiensis is retained at an intermediate position. Since S. czerskii is a valid species in the S. nigripinnis clade, remaining samples of S. nigripinnis form a paraphyly. This speciation process is attributed to geographical isolation and special environmental conditions experienced by S. czerskii and stable environments experienced by the other S. nigripinnis populations. This type of speciation process was suggested to be very common. Samples of Sarcocheilichthys sinensis sinensis and Sarcocheilichthys sinensis fukiensis that did not form their own monophyletic groups suggest an early stage of speciation and support their sub-species status. Molecular clock analysis indicates that the two major lineages of the genus Sarcocheilichthys, clades I and II diverged c. 8ˇ89 million years ago (mya). Sarcocheilichthys v. microoculus from Japan probably diverged 4ˇ78 mya from the Chinese group. The northern,southern clades of S. nigripinnis began to diverge c. 2ˇ12 mya, while one lineage of S. nigripinnis evolved into a new species, S. czerski, c. 0ˇ34 mya. [source] PHYLOGENETIC RELATIONSHIPS WITHIN THE GENUS HYPNEA (GIGARTINALES, RHODOPHYTA), WITH A DESCRIPTION OF H. CAESPITOSA SP.JOURNAL OF PHYCOLOGY, Issue 2 2010Species discrimination within the gigartinalean red algal genus Hypnea has been controversial. To help resolve the controversy and explore phylogeny within the genus, we determined rbcL sequences from 30 specimens of 23 species within the genus, cox1 from 22 specimens of 10 species, and psaA from 16 species. We describe H. caespitosa as a new species characterized by a relatively slender main axis; a pulvinate growth habit with entangled, anastomosing, and subulate uppermost branches; and unilaterally borne tetrasporangial sori. The new species occurs in the warm waters of Malaysia, the Philippines, and Singapore. The phylogenetic trees of rbcL, psaA, and cox1 sequences showed a distant relationship of H. caespitosa to H. pannosa J. Agardh from Baja California and the marked differentiation from other similar species. The rbcL + psaA tree supported monophyly of the genus with high bootstrap values and posterior probabilities. The analysis revealed three clades within the genus, corresponding to three sections, namely, Virgatae, Spinuligerae, and Pulvinatae first recognized by J. G. Agardh. Exceptions were H. japonica T. Tanaka in Pulvinatae and H. spinella (C. Agardh) Kütz. in Spinuligerae. [source] MONOPHYLY OF THE GENUS CLOSTERIUM AND THE ORDER DESMIDIALES (CHAROPHYCEAE, CHLOROPHYTA) INFERRED FROM NUCLEAR SMALL SUBUNIT rDNA DATAJOURNAL OF PHYCOLOGY, Issue 6 2001Takashi Denboh We newly sequenced the nuclear-encoded small subunit (SSU) rDNA coding region for 21 taxa of the genus Closterium. The new sequences were integrated into an alignment with 13 known sequences of conjugating green algae representing six traditional families (i.e. Zygnemataceae, Mesotaeniaceae, Gonatozygaceae, Peniaceae, Closteriaceae, and Desmidiaceae) and five known charophycean sequences as outgroups. Both maximum likelihood and maximum parsimony analyses supported with high bootstrap values one large clade containing all placoderm desmids (Desmidiales). All the Closterium taxa formed one clade with 100% bootstrap support, indicating their monophyly, but not paraphyly, as suggested earlier. As to the taxa within the genus Closterium, we found two clades of morphologically closely related taxa in both maximum likelihood and maximum parsimony trees. They corresponded to the C. calosporum species complex and the C. moniliferum-ehrenbergii species complex. It is of particular interest that the homothallic entity of C. moniliferum v. moniliferum was distinguished from and ancestral to all other entities of the C. moniliferum-ehrenbergii species complex. Superimposing all 50 charophycean sequences on the higher order SSU rRNA structure model of Closterium, we investigated degrees of nucleotide conservation at a given position in the nucleotide sequence. A characteristic "signature" structure to the genus Closterium was found as an additional helix at the tip of V1 region. In addition, eight base deletions at the tip of helix 10 were found to be characteristic of the C. calosporum species complex, C. gracile, C. incurvum, C. pleurodermatum, and C. pusillum v. maius. These taxa formed one clade with an 82% bootstrap value in maximum parsimony analysis. [source] Isolation and characterization of microsatellite markers from guineagrass (Panicum maximum) for genetic diversity estimate and cross-species amplificationPLANT BREEDING, Issue 1 2010A. Chandra With 1 figure and 1 table Abstract Guineagrass (Panicum maximum Jacq.) is one of the major forage grasses in tropical and semitropical regions, largely apomictic and predominantly exist as tetraploid. Non-availability of polymorphic molecular markers has been a major limitation in its characterization and improvement. We report isolation and characterization of microsatellites in P. maximum and cross-species results with other five Panicum species. Based on microsatellite-motifs, 15 functional and polymorphic simple sequence repeat (SSR) primer-pairs were designed, validated and employed in estimating genetic relationship among 34 guineagrass accessions. Thirteen primer-pairs amplified single locus and remaining two generated more than two loci with an average of 3.57 bands per locus amounts to 63 bands with 34 guineagrass accessions. Average expected heterozygosity (HE) of 0.35 (maximum 0.97) and observed heterozygosity (HO) of 0.37 (maximum 0.91) established the efficiency of developed markers for discriminating guineagrass accessions. Dice's similarity coefficients-based unweighted pair group with arithmetic average method-clustering supported with high bootstrap values (,40) indicated its significance and distinguished all accessions except IG97-93 and IG97-6. Utility of these new SSR loci in genetic diversity study of P. maximum and other cross,amplified species is discussed. [source] Genetic variation of coxsackie virus B5 strains associated with aseptic meningitis in GreeceCLINICAL MICROBIOLOGY AND INFECTION, Issue 7 2006A. Papa Abstract In order to explore the genetic relationships among coxsackie virus B5 strains in Greece, the nucleotide sequences of the partial VP1 gene in strains isolated from aseptic cases of meningitis were determined and compared with those of strains isolated from other countries. Phylogenetic analysis showed a high degree of divergence (25%) among Greek strains isolated in different years, which clustered with high bootstrap values in a different subgroup of viruses, suggesting that enterovirus types vary with time rather than geographical distribution. A non-synonymous mutation present in the strains of this study was not observed in other coxsackie virus B5 strains. [source] | ||||||||||