Molecular phylogeny of European Fucales (Phaeophyceae) based on partial large-subunit rDNA sequence comparisons

Giardia lamblia telomeres have been isolated from a library enriched for repaired chromosome ends by (i) screening with a Plasmodium falciparum telomere and (ii) differential hybridization with Bal 31-digested and total G. lamblia DNA. Analysis of three clones isolated by this strategy has identified multiple tandem repeats of the 5-mer TAGGG. An oligonucleotide containing these repeats recognizes Bal 31-sensitive bands in Southern hybridizations and detects all G. lamblia chromosomes in pulsed-field gel electrophoresis separations. An abrupt transition from the G. lamblia rDNA sequence to telomeric repeats has been found in all three clones. In two of the clones the transition occurs at the same site, near the beginning of the large subunit rDNA sequence. In the third clone the transition occurs at a site in the intergenic spacer sequence between the rDNA genes. Hybridization of an rDNA probe to a pulsed-field separation of G. lamblia chromosomes indicates that rDNA genes are present on several chromosomes but vary in location from isolate to isolate. These results suggest that rRNA genes are clustered at telomeric locations in G. lamblia and that these clusters are mobile.

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Revisiting the phylogeny of Ocellularieae, the second largest tribe within Graphidaceae (lichenized Ascomycota: Ostropales)

Phytotaxa ◽

10.11646/phytotaxa.189.1.6 ◽

2014 ◽

Vol 189 (1) ◽

pp. 52 ◽

Cited By ~ 15

Author(s):

Ekaphan Kraichak ◽

Sittiporn Parnmen ◽

Robert Lücking ◽

EIMY RIVAS PLATA ◽

André Aptroot ◽

...

Keyword(s):

Molecular Phylogeny ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Large Subunit ◽

Small Subunit ◽

New Combinations ◽

New Name ◽

Small Subunit Rdna ◽

Large Subunit Rdna ◽

First Time

We present an updated 3-locus molecular phylogeny of tribe Ocellularieae, the second largest tribe within subfamily Graphidoideae in the Graphidaceae. Adding 165 newly generated sequences from the mitochondrial small subunit rDNA (mtSSU), the nuclear large subunit rDNA (nuLSU), and the second largest subunit of the DNA-directed RNA polymerase II (RPB2), we currently distinguish 218 species among the sequenced material, including the outgroup. This corresponds to almost half the species at this point recognized within this tribe. The newly generated sequences include 23 newly described species and one newly described genus published elsewhere in this volume. For the first time, Sarcographina cyclospora Müll. Arg., in spite of its distinctly lirellate ascomata, is shown to belong in tribe Ocellularieae, as strongly supported sister to Ocellularia inturgescens (Müll. Arg.) Mangold. The following six new combinations are proposed: Melanotrema lynceodes (Nyl.) Rivas Plata, Lücking & Lumbsch, Ocellularia curranii (Vain.) Kraichak, Lücking & Lumbsch, O. khasiana (Patw. & Nagarkar) Kraichak, Lücking & Lumbsch, O. cinerea (Müll. Arg.) Kraichak, Lücking & Lumbsch, O. erodens (R. C. Harris) Kraichak, Lücking & Lumbsch, and O. laeviuscula (Nyl) Kraichak, Lücking & Lumbsch. Further, the new name Ocellularia hernandeziana Kraichak, Lücking & Lumbsch is introduced for Myriotrema ecorticatum. The nomenclatural status of the name Ocellularia microstoma is clarified.

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Telomeric location of Giardia rDNA genes

Molecular and Cellular Biology ◽

10.1128/mcb.11.6.3326-3330.1991 ◽

1991 ◽

Vol 11 (6) ◽

pp. 3326-3330

Author(s):

R D Adam ◽

T E Nash ◽

T E Wellems

Keyword(s):

Tandem Repeats ◽

Dna Analysis ◽

Large Subunit ◽

Intergenic Spacer ◽

Rdna Sequence ◽

Rrna Genes ◽

Rdna Genes ◽

Pulsed Field ◽

Large Subunit Rdna ◽

A Site

Giardia lamblia telomeres have been isolated from a library enriched for repaired chromosome ends by (i) screening with a Plasmodium falciparum telomere and (ii) differential hybridization with Bal 31-digested and total G. lamblia DNA. Analysis of three clones isolated by this strategy has identified multiple tandem repeats of the 5-mer TAGGG. An oligonucleotide containing these repeats recognizes Bal 31-sensitive bands in Southern hybridizations and detects all G. lamblia chromosomes in pulsed-field gel electrophoresis separations. An abrupt transition from the G. lamblia rDNA sequence to telomeric repeats has been found in all three clones. In two of the clones the transition occurs at the same site, near the beginning of the large subunit rDNA sequence. In the third clone the transition occurs at a site in the intergenic spacer sequence between the rDNA genes. Hybridization of an rDNA probe to a pulsed-field separation of G. lamblia chromosomes indicates that rDNA genes are present on several chromosomes but vary in location from isolate to isolate. These results suggest that rRNA genes are clustered at telomeric locations in G. lamblia and that these clusters are mobile.

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Molecular phylogeny reveals the true colours of Myeloconidaceae (Ascomycota: Ostropales)

Australian Systematic Botany ◽

10.1071/sb13040 ◽

2014 ◽

Vol 27 (1) ◽

pp. 38 ◽

Cited By ~ 7

Author(s):

Matthew P. Nelsen ◽

Robert Lücking ◽

Carrie J. Andrew ◽

André Aptroot ◽

Marcela E. S. Cáceres ◽

...

Keyword(s):

Molecular Phylogeny ◽

Species Concept ◽

Large Subunit ◽

Molecular Data ◽

Small Subunit ◽

Separate Genus ◽

The Family ◽

Single Genus ◽

Ascospore Septation ◽

Large Subunit Rdna

The lichen-forming fungal family Myeloconidaceae, with the single genus Myeloconis, has been suggested to share affinities with Porinaceae (Lecanoromycetes: Ostropales). We examined its position relative to this family by using molecular data from the mitochondrial small-subunit and nuclear large-subunit rDNA. Our results revealed that Myeloconis forms a monophyletic group nested within Porinaceae, closely related to Porina farinosa. Neither Porina s.str. nor Clathroporina sensu Harris form monophyletic groups; instead, two strongly supported clades were recovered, which differ in ascospore septation (septate v. muriform), with the clade producing muriform ascospores including Myeloconis. We therefore reduce Myeloconidaceae to synonymy with Porinaceae; however, because generic delimitations within Porinaceae remain unclear, we retain Myeloconis as a separate genus within the family. The species concept currently used in the genus, based largely on secondary metabolites and ascospore measurements, is supported by the phylogeny.

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A molecular phylogeny of the Dactylogyridae sensu Kritsky & Boeger (1989) (Monogenea) based on the D1-D3 domains of large subunit rDNA

Parasitology ◽

10.1017/s0031182006009942 ◽

2006 ◽

Vol 133 (01) ◽

pp. 43 ◽

Cited By ~ 44

Author(s):

A. ŠIMKOVÁ ◽

I. MATEJUSOVÁ ◽

C. O. CUNNINGHAM

Keyword(s):

Molecular Phylogeny ◽

Large Subunit ◽

Large Subunit Rdna

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Molecular phylogeny resolves a taxonomic misunderstanding and places Geisleria close to Absconditella s. str. (Ostropales: Stictidaceae)

The Lichenologist ◽

10.1017/s0024282913000741 ◽

2014 ◽

Vol 46 (1) ◽

pp. 115-128 ◽

Cited By ~ 13

Author(s):

André APTROOT ◽

Sittiporn PARNMEN ◽

Robert LÜCKING ◽

Elisabeth BALOCH ◽

Patricia JUNGBLUTH ◽

...

Keyword(s):

Molecular Phylogeny ◽

Type Species ◽

Sequence Data ◽

Large Subunit ◽

Parallel Evolution ◽

Small Subunit ◽

Phylogenetic Position ◽

Pioneer Species ◽

Dry Conditions ◽

Large Subunit Rdna

AbstractThe phylogenetic position of the genus Geisleria and its type species G. sychnogonioides was reconstructed using sequence data of the mitochondrial small subunit (mtSSU), the nuclear large subunit rDNA (nuLSU) and the first subunit of the RNA polymerase (RPB1). The species, previously classified in Verrucariaceae (Eurotiomycetes) and Strigulaceae (Dothideomycetes), is sister to the type of the genus Absconditella, A. sphagnorum, and nested within the genera Absconditella and Cryptodiscus combined (which also includes the lichenized Bryophagus). At first glance it appears to be a further example of parallel evolution of perithecioid ascomata within Stictidaceae (Lecanoromycetes: Ostropales), besides Ostropa and Robergea, adding to the growing list of perithecioid forms nested within apothecioid lineages in Ostropomycetidae, and specifically Ostropales, with other examples known from Graphidaceae (several genera), Gyalectaceae (Belonia), and Porinaceae. However, revision of type material collected by Nitschke revealed that the species actually develops typical apothecia with a narrowly exposed disc. We conclude that Geisleria sychnogonoides was erroneously considered a pyrenocarpous taxon, because in dry conditions the apothecia are closed and not recognizable as such. The species usually grows on unstable soil and therefore often only develops young, more or less closed ascomata (yet with mature ascospores), and has also been confused with the superficially similar Belonia incarnata, in which the ascomata remain closed even when mature. Geisleriasychnogonioides has so far only been known as a rarely reported pioneer species from loamy soils in Europe and North America. Here it is reported to occur abundantly on lateritic soils in subtropical Brazil, suggesting that it is cosmopolitan and possibly common, but much overlooked.

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