Small subunit rDNA phylogeny shows the lichen families Caliciaceae and Physciaceae (Lecanorales, Ascomycotina) to form a monophyletic group

2000 ◽  
Vol 78 (2) ◽  
pp. 246-254 ◽  
Author(s):  
Mats Wedin ◽  
Heidi Döring ◽  
Anders Nordin ◽  
Leif Tibell
Keyword(s):  
Sister Group ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Surface Structures ◽  
Monophyletic Group ◽  
Spore Surface ◽  
Rdna Sequences ◽  
Small Subunit Rdna ◽  
Xanthoria Parietina ◽  
The Relationship

A phylogenetic analysis based on small subunit (SSU) rDNA sequences shows the lecanoralean lichen families Caliciaceae and Physciaceae form a well-supported monophyletic group within the order Lecanorales (Ascomycotina). Support for this relationship is present from anatomical data, in particular data from spore ontogeny, where close similarities between the pattern of development of spore surface structures in the two families are pointed out. The Caliciaceae-Physciaceae group is characterized by having thick-walled, pigmented spores, often with a distinctive ornamentation which is usually formed either from strongly melanized parts of the perispore, separated by nonmelanized, gelatinous parts that eventually dissolve, or by cracks in the perispore. The relationship to the Teloschistaceae, sometimes suggested as a possible sister-group to the Physciaceae, was not supported by jackknifing, but cannot be rejected with the present data. There is no support for the suggested order Teloschistales. A brief discussion of the evolution of the prototunicate ascus in the Lecanorales is given. New SSU rDNA sequences were produced from Buellia disciformis (Fr.) Mudd. and Physcia aipolia (Humb.) Fürnr. (Physciaceae), Cladonia sulphurina (Michx.) Fr. (Cladoniaceae), Cyphelium tigillare (Ach.) Ach. (Caliciaceae), and Caloplaca flavorubescens (Huds.) J.R. Laundon and Xanthoria parietina (L.) Th.Fr. (Teloschistaceae).Key words: 18S, fungi, lichens, molecular phylogeny, ribosomal DNA.

Molecular characterisation of some species of Mylonchulus (Nematoda: Mononchida) from Japan and comments on the status of Paramylonchulus and Pakmylonchulus

Nematology ◽  
2009 ◽  
Vol 11 (3) ◽  
pp. 337-342 ◽  
Author(s):  
Masaaki Araki ◽  
Wasim Ahmad ◽  
Majid Olia ◽  
Nobuhiro Minaka
Keyword(s):  
Phylogenetic Trees ◽  
Sequence Data ◽  
Preliminary Investigation ◽  
Sister Group ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Rdna Sequences ◽  
The Status ◽  
Molecular Relationships ◽  
The Relationship

AbstractComparative analyses of different regions of ribosomal DNA have become a popular tool in understanding the relationship among different species and genera and nematodes are no exception to this. In this study, molecular relationships were inferred from a nearly complete small subunit (SSU) of total 16 OTUs for five species of Mylonchulus, Paramylonchulus and Pakmylonchulus collected from various parts of Japan with two out-group taxa (Mononchus aquaticus and Clarkus papillatus) to examine the relationship among these species. Out of 1685 bp SSU rDNA sequences, phylogenetic trees using distance (NJ), parsimony and likelihood algorithms were performed. Obtained tree topologies were stable across algorithms and sequence data show that populations of the same species clustered together and four out of five species (M. brachyuris, M. hawaiiensis, M. oceanicus, M. sigmaturus) formed a monophyletic assemblage while M. mulveyi formed a sister group. Populations of species lacking subventral teeth but with a double gonad (M. oceanicus) stand with other Mylonchulus species, thereby confirming the synonymy of Pakmylonchulus, while populations with a narrow buccal cavity with few rows of denticles, no subventral teeth and a single prodelphic gonad (M. mulveyi = Paramylonchulus mulveyi) support to some extent the validity of the genus Paramylonchulus. Though a preliminary investigation, it is the first report on molecular relationships in Mylonchulus, probably a paraphyletic genus. Our results suggest that SSU rDNA sequence data are useful in understanding the relationship between genera and species.

scholarly journals The endemic Cladophorales (Ulvophyceae) of ancient Lake Baikal represent a monophyletic group of very closely related but morphologically diverse species

2020 ◽  
Author(s):  
C Boedeker ◽  
F Leliaert ◽  
OA Timoshkin ◽  
VS Vishnyakov ◽  
S Díaz-Martínez ◽  
...  
Keyword(s):  
Lake Baikal ◽  
Phylogenetic Signal ◽  
Small Subunit ◽  
Monophyletic Group ◽  
Species Flock ◽  
Surprising Result ◽  
Internal Transcribed Spacer Region ◽  
Rdna Sequences ◽  
Green Algal ◽  
Small Subunit Rdna

© 2018 Phycological Society of America Lake Baikal, the oldest lake in the world, is home to spectacular biodiversity and extraordinary levels of endemism. While many of the animal species flocks from Lake Baikal are famous examples of evolutionary radiations, the lake also includes a wide diversity of endemic algae that are not well investigated with regards to molecular-biological taxonomy and phylogeny. The endemic taxa of the green algal order Cladophorales show a range of divergent morphologies that led to their classification in four genera in two families. We sequenced partial large- and small-subunit rDNA as well as the internal transcribed spacer region of 14 of the 16 described endemic taxa to clarify their phylogenetic relationships. One endemic morphospecies, Cladophora kusnetzowii, was shown to be conspecific with the widespread Aegagropila linnaei. All other endemic morphospecies formed a monophyletic group nested within the genus Rhizoclonium (Cladophoraceae), a very surprising result, in stark contrast to their morphological affinities. The Baikal clade represents a species flock of closely related taxa with very low genetic differentiation. Some of the morphospecies were congruent with lineages recovered in the phylogenies, but due to the low phylogenetic signal in the rDNA sequences the relationships within the Baikal clade were not all well resolved. The Baikal clade appears to represent a recent radiation, based on the low molecular divergence within the group, and it is hypothesized that the large morphological variation results from diversification in sympatry from a common ancestor in Lake Baikal.

scholarly journals The endemic Cladophorales (Ulvophyceae) of ancient Lake Baikal represent a monophyletic group of very closely related but morphologically diverse species

2020 ◽  
Author(s):  
C Boedeker ◽  
F Leliaert ◽  
OA Timoshkin ◽  
VS Vishnyakov ◽  
S Díaz-Martínez ◽  
...  
Keyword(s):  
Lake Baikal ◽  
Phylogenetic Signal ◽  
Small Subunit ◽  
Monophyletic Group ◽  
Species Flock ◽  
Surprising Result ◽  
Internal Transcribed Spacer Region ◽  
Rdna Sequences ◽  
Green Algal ◽  
Small Subunit Rdna

© 2018 Phycological Society of America Lake Baikal, the oldest lake in the world, is home to spectacular biodiversity and extraordinary levels of endemism. While many of the animal species flocks from Lake Baikal are famous examples of evolutionary radiations, the lake also includes a wide diversity of endemic algae that are not well investigated with regards to molecular-biological taxonomy and phylogeny. The endemic taxa of the green algal order Cladophorales show a range of divergent morphologies that led to their classification in four genera in two families. We sequenced partial large- and small-subunit rDNA as well as the internal transcribed spacer region of 14 of the 16 described endemic taxa to clarify their phylogenetic relationships. One endemic morphospecies, Cladophora kusnetzowii, was shown to be conspecific with the widespread Aegagropila linnaei. All other endemic morphospecies formed a monophyletic group nested within the genus Rhizoclonium (Cladophoraceae), a very surprising result, in stark contrast to their morphological affinities. The Baikal clade represents a species flock of closely related taxa with very low genetic differentiation. Some of the morphospecies were congruent with lineages recovered in the phylogenies, but due to the low phylogenetic signal in the rDNA sequences the relationships within the Baikal clade were not all well resolved. The Baikal clade appears to represent a recent radiation, based on the low molecular divergence within the group, and it is hypothesized that the large morphological variation results from diversification in sympatry from a common ancestor in Lake Baikal.

scholarly journals Quantitative Measure of Small-Subunit rRNA Gene Sequences of the Kingdom Korarchaeota

1998 ◽  
Vol 64 (12) ◽  
pp. 5064-5066 ◽  
Author(s):  
Clifford F. Brunk ◽  
Nicole Eis
Keyword(s):  
Internal Standard ◽  
Pcr Amplification ◽  
Quantitative Measure ◽  
Pcr Primers ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Rdna Sequence ◽  
Rrna Gene ◽  
Small Subunit Rrna ◽  
Rdna Sequences

ABSTRACT Comparative PCR amplification of small-subunit (SSU) rRNA gene (rDNA) sequences indicates substantial preferential PCR amplification of pJP27 sequences with korarchaeote-specific PCR primers. The coamplification of a modified SSU rDNA sequence can be used as an internal standard to determine the amount of a specific SSU rDNA sequence.

On the phylogeny of Ophiostoma, Ceratocystis s.s., and Microascus, and relationships within Ophiostoma based on partial ribosomal DNA sequences

1993 ◽  
Vol 71 (9) ◽  
pp. 1249-1265 ◽  
Author(s):  
G. Hausner ◽  
J. Reid ◽  
G. R. Klassen
Keyword(s):  
Dna Sequences ◽  
Sequence Data ◽  
Large Subunit ◽  
Small Subunit ◽  
Data Set ◽  
Rdna Sequences ◽  
Morphological Criteria ◽  
Small Subunit Rdna ◽  
Rdna Sequence Data ◽  
Large Subunit Rdna

Phylogenetic analysis of partial rDNA sequences suggests that Ophiostoma should remain the sole genus of the Ophiostomataceae, and this should be the sole family within the Ophiostomatales, whereas Ceratocystis s.s. would be best disposed within the Microascales. Although morphological criteria suggest that the genus Ophiostoma is heterogeneous, analysis of partial small subunit rDNA sequence data shows that Ophiostoma (excluding O. roraimense) represents a monophyletic taxon. Analysis of a partial large subunit rDNA data set, which included sequences from 55 species assignable to Ophiostoma, failed to support the strict subdivision of the genus based on either ascospore characters or the nature of the anamorph. Key words: Ceratocystis, Microascus, Ophiostoma, partial rDNA sequences, phylogeny.

Evolution of RuminantSarcocystis(Sporozoa) Parasites Based on Small Subunit rDNA Sequences

1999 ◽  
Vol 11 (1) ◽  
pp. 27-37 ◽  
Author(s):  
O.J.M. Holmdahl ◽  
David A. Morrison ◽  
John T. Ellis ◽  
Lam T.T. Huong
Keyword(s):  
Small Subunit ◽  
Rdna Sequences ◽  
Small Subunit Rdna

Taxonomy of Kudoa species (Myxosporea), using a small-subunit ribosomal DNA sequence

1997 ◽  
Vol 75 (12) ◽  
pp. 2112-2119 ◽  
Author(s):  
D. M. L. Hervio ◽  
J. Khattra ◽  
R. H. Devlin ◽  
M. L. Kent ◽  
J. Sakanari ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Coho Salmon ◽  
Geographic Location ◽  
Small Subunit ◽  
Ssu Rdna ◽  
Polymerase Chain Reaction Test ◽  
Sequence Comparisons ◽  
Rdna Sequences ◽  
Commercial Species ◽  
Chain Reaction Test

Myxosporeans in the genus Kudoa infect the flesh of many marine fishes and often cause unsightly lesions and softening of the flesh texture. We are particularly interested in K. thyrsites because it is associated with soft flesh in the Atlantic salmon (Salmo solar), an important commercial species in Canada. Sequences of the small-subunit (SSU) rDNA (about 1600 base pairs) were obtained from K. miniauriculata, K. amanuensis, and K. poniformis. We aligned these sequences with one obtained from coho salmon (Oncorhynchus kisutch) and designed "Kudoa general" primers (KUD1f and KUD2r). These primers, in combination with other general primers, were then used to obtain the SSU rDNA sequence of K. thyrsites from two host species, Atlantic salmon and tubesnout (Aulorhynchus flavidus), from British Columbia, Canada. Sequence comparisons of these isolates indicated that Kudoa species cluster by geographic location rather than by morphology of spores. The three species from the eastern Pacific were approximately 97% identical, whereas K. amamiensis (from Japan) was about 91% identical with these species. Sequence comparisons of K. thyrsites from Atlantic salmon and tubesnout revealed a difference of only 0.07% between these isolates. Comparison of SSU rDNA sequences from the four Kudoa species and Henneguya salminicolo analyzed in this study with those from other available myxosporean genera (Myxidium and Myxoholus) showed that taxonomic divisions at the order and suborder levels were consistent with classical views of the taxonomy of the Myxosporea. Using specific regions of the SSU rDNA, we also developed a sensitive and specific polymerase chain reaction test for detection of K. thyrsites.

Sign in / Sign up

Export Citation Format

Share Document