The interplay between host biogeography and phylogeny in structuring diversification of the feather louse genus Penenirmus

Parasite diversification is influenced by many of the same factors that affect speciation of free-living organisms, such as biogeographic barriers. However, the ecology and evolution of the host lineage also has a major impact on parasite speciation. Here we explore the interplay between biogeography and host-association on the pattern of diversification in a group of ectoparasitic lice (Insecta: Phthiraptera: Penenirmus) that feeds on the feathers of woodpeckers, barbets, and honeyguides (Piciformes) and some songbirds (Passeriformes). We use whole genome sequencing of 41 ingroup and 12 outgroup samples to develop a phylogenomic dataset of DNA sequences from a reference set of 2,395 single copy ortholog genes, for a total of nearly four million aligned base positions. The phylogenetic trees resulting from both concatenated and gene-tree/species-tree coalescent analyses were nearly identical and highly supported. These trees recovered the genus Penenirmus as monophyletic and identified several major clades, which tended to be associated with one major host group. However, cophylogenetic analysis revealed that host-switching was a prominent process in the diversification of this group. This host-switching generally occurred within single major biogeographic regions. We did, however, find one case in which it appears that a rare dispersal event by a woodpecker lineage from North America to Africa allowed its associated louse to colonize a woodpecker in Africa, even though the woodpecker lineage from North America never became established there.

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Phylogeny of Trematomus (Notothenioidei: Nototheniidae) inferred from mitochondrial and nuclear gene sequences

Antarctic Science ◽

10.1017/s0954102009990253 ◽

2009 ◽

Vol 21 (6) ◽

pp. 565-570 ◽

Cited By ~ 15

Author(s):

Kristen L. Kuhn ◽

Thomas J. Near

Keyword(s):

Dna Sequences ◽

Phylogenetic Relationships ◽

Phylogenetic Trees ◽

Sequence Data ◽

Phylogenetic Analyses ◽

Nuclear Gene ◽

Single Copy ◽

Morphological Characters ◽

Mitochondrial Genes ◽

Phylogenetic Resolution

AbstractThe biota of Antarctica is amazingly rich and highly endemic. The phylogenetics of notothenioid fishes has been extensively investigated through analyses of morphological characters, DNA sequences from mitochondrial genes, and single copy nuclear genes. These phylogenetic analyses have produced reasonably similar phylogenetic trees of notothenioids, however a number of phylogenetic questions remain. The nototheniid clade Trematomus is an example of a group where phylogenetic relationships remain unresolved. In this paper we revisit the phylogenetic relationships of Trematomus using both increased taxon sampling and an expanded dataset which includes DNA sequences from two mitochondrial genes (ND2 and 16S rRNA) and one single-copy nuclear gene (RPS7). The Bayesian phylogeny resulting from the analysis of the combined mitochondrial and nuclear gene datasets was well resolved and contained more interspecific nodes supported with significant Bayesian posteriors than either the mitochondrial or nuclear gene phylogenies alone. This demonstrates that the addition of nuclear gene sequence data to mitochondrial data can enhance phylogenetic resolution and increase node support. Additionally, the results of the combined mitochondrial and nuclear Bayesian analyses provide further support for the inclusion of species previously classified as Pagothenia and Cryothenia in Trematomus.

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Nucleotide polymorphisms in three genes support host and geographic speciation in tree pathogens belonging toGremmeniellaspp.

Canadian Journal of Botany ◽

10.1139/b02-103 ◽

2002 ◽

Vol 80 (11) ◽

pp. 1151-1159 ◽

Cited By ~ 8

Author(s):

M Dusabenyagasani ◽

G Laflamme ◽

R C Hamelin

Keyword(s):

North America ◽

Dna Sequences ◽

North American ◽

Abies Balsamea ◽

Host Specialization ◽

Rrna Genes ◽

Nucleotide Polymorphisms ◽

Group I ◽

Geographic Separation ◽

Pinus Spp

We detected nucleotide polymorphisms within the genus Gremmeniella in DNA sequences of β-tubulin, glyceraldehyde phosphate dehydrogenase, and mitochondrial small subunit rRNA (mtSSU rRNA) genes. A group-I intron was present in strains originating from fir (Abies spp.) in the mtSSU rRNA locus. This intron in the mtSSU rRNA locus of strains isolated from Abies sachalinensis (Fridr. Schmidt) M.T. Mast in Asia was also found in strains isolated from Abies balsamea (L.) Mill. in North America. Phylogenetic analyses yielded trees that grouped strains by host of origin with strong branch support. Asian strains of Gremmeniella abietina (Lagerberg) Morelet var. abietina isolated from fir (A. sachalinensis) were more closely related to G. abietina var. balsamea from North America, which is found on spruce (Picea spp.) and balsam fir, and European and North American races of G. abietina var. abietina from pines (Pinus spp.) were distantly related. Likewise, North American isolates of Gremmeniella laricina (Ettinger) O. Petrini, L.E. Petrini, G. Laflamme, & G.B. Ouellette, a pathogen of larch, was more closely related to G. laricina from Europe than to G. abietina var. abietina from North America. These data suggest that host specialization might have been the leading evolutionary force shaping Gremmeniella spp., with geographic separation acting as a secondary factor.Key words: Gremmeniella, geographic separation, host specialization, mitochondrial rRNA, nuclear genes.

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Bayes Estimation of Species Divergence Times and Ancestral Population Sizes Using DNA Sequences From Multiple Loci

Genetics ◽

10.1093/genetics/164.4.1645 ◽

2003 ◽

Vol 164 (4) ◽

pp. 1645-1656 ◽

Cited By ~ 3

Author(s):

Bruce Rannala ◽

Ziheng Yang

Keyword(s):

Dna Sequences ◽

Gene Tree ◽

Species Tree ◽

Bayes Estimation ◽

Ancestral Population ◽

Divergence Times ◽

Gene Trees ◽

Species Divergence ◽

Multiple Loci ◽

Population Sizes

Abstract The effective population sizes of ancestral as well as modern species are important parameters in models of population genetics and human evolution. The commonly used method for estimating ancestral population sizes, based on counting mismatches between the species tree and the inferred gene trees, is highly biased as it ignores uncertainties in gene tree reconstruction. In this article, we develop a Bayes method for simultaneous estimation of the species divergence times and current and ancestral population sizes. The method uses DNA sequence data from multiple loci and extracts information about conflicts among gene tree topologies and coalescent times to estimate ancestral population sizes. The topology of the species tree is assumed known. A Markov chain Monte Carlo algorithm is implemented to integrate over uncertain gene trees and branch lengths (or coalescence times) at each locus as well as species divergence times. The method can handle any species tree and allows different numbers of sequences at different loci. We apply the method to published noncoding DNA sequences from the human and the great apes. There are strong correlations between posterior estimates of speciation times and ancestral population sizes. With the use of an informative prior for the human-chimpanzee divergence date, the population size of the common ancestor of the two species is estimated to be ∼20,000, with a 95% credibility interval (8000, 40,000). Our estimates, however, are affected by model assumptions as well as data quality. We suggest that reliable estimates have yet to await more data and more realistic models.

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Mapping by Sequencing the Pneumocystis Genome Using the Ordering DNA Sequences V3 Tool

Genetics ◽

10.1093/genetics/163.4.1299 ◽

2003 ◽

Vol 163 (4) ◽

pp. 1299-1313

Author(s):

Zheng Xu ◽

Britton Lance ◽

Claudia Vargas ◽

Budak Arpinar ◽

Suchendra Bhandarkar ◽

...

Keyword(s):

Physical Mapping ◽

Dna Sequences ◽

Pneumocystis Carinii ◽

Single Copy ◽

Fungal Genome ◽

Mapping Data ◽

Genome Database ◽

Rdna Genes ◽

Genome Map ◽

Mapping By Sequencing

Abstract A bioinformatics tool called ODS3 has been created for mapping by sequencing. The tool allows the creation of integrated genomic maps from genetic, physical mapping, and sequencing data and permits an integrated genome map to be stored, retrieved, viewed, and queried in a stand-alone capacity, in a client/server relationship with the Fungal Genome Database (FGDB), and as a web-browsing tool for the FGDB. In that ODS3 is programmed in Java, the tool promotes platform independence and supports export of integrated genome-mapping data in the extensible markup language (XML) for data interchange with other genome information systems. The tool ODS3 is used to create an initial integrated genome map of the AIDS-related fungal pathogen, Pneumocystis carinii. Contig dynamics would indicate that this physical map is ∼50% complete with ∼200 contigs. A total of 10 putative multigene families were found. Two of these putative families were previously characterized in P. carinii, namely the major surface glycoproteins (MSGs) and HSP70 proteins; three of these putative families (not previously characterized in P. carinii) were found to be similar to families encoding the HSP60 in Schizosaccharomyces pombe, the heat-shock Ψ protein in S. pombe, and the RNA synthetase family (i.e., MES1) in Saccharomyces cerevisiae. Physical mapping data are consistent with the 16S, 5.8S, and 26S rDNA genes being single copy in P. carinii. No other fungus outside this genus is known to have the rDNA genes in single copy.

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Inter- and Intra-Continental Genetic Variation in the Generalist Conifer Wood Saprobic Fungus Phlebiopsis gigantea

Forests ◽

10.3390/f12060751 ◽

2021 ◽

Vol 12 (6) ◽

pp. 751

Author(s):

Francesco Dovana ◽

Paolo Gonthier ◽

Matteo Garbelotto

Keyword(s):

North America ◽

Genetic Differentiation ◽

Dna Sequences ◽

North American ◽

Fungal Species ◽

Coniferous Forests ◽

Native Forest ◽

Western North America ◽

Phlebiopsis Gigantea ◽

Conifer Wood

Phlebiopsis gigantea (Fr.) Jülich is a well-known generalist conifer wood saprobe and a biocontrol fungus used in several world countries to prevent stump infection by tree pathogenic Heterobasidion fungal species. Previous studies have reported the presence of regional and continental genetic differentiation in host-specific fungi, but the presence of such differentiation for generalist wood saprobes such as P. gigantea has not been often studied or demonstrated. Additionally, little information exists on the distribution of this fungus in western North America. The main purposes of this study were: (I) to assess the presence of P. gigantea in California, (II) to explore the genetic variability of P. gigantea at the intra and inter-continental levels and (III) to analyze the phylogeographic relationships between American and European populations. Seven loci (nrITS, ML5–ML6, ATP6, RPB1, RPB2, GPD and TEF1-α) from 26 isolates of P. gigantea from coniferous forests in diverse geographic distribution and from different hosts were analyzed in this study together with 45 GenBank sequences. One hundred seventy-four new sequences were generated using either universal or specific primers designed in this study. The mitochondrial ML5–ML6 DNA and ATP6 regions were highly conserved and did not show differences between any of the isolates. Conversely, DNA sequences from the ITS, RPB1, RPB2, GPD and TEF1-α loci were variable among samples. Maximum likelihood analysis of GPD and TEF1-α strongly supported the presences of two different subgroups within the species but without congruence or geographic partition, suggesting the presence of retained ancestral polymorphisms. RPB1 and RPB2 sequences separated European isolates from American ones, while the GPD locus separated western North American samples from eastern North American ones. This study reports the presence of P. gigantea in California for the first time using DNA-based confirmation and identifies two older genetically distinct subspecific groups, as well as three genetically differentiated lineages within the species: one from Europe, one from eastern North America and one from California, with the latter presumably including individuals from the rest of western North America. The genetic differentiation identified here among P. gigantea individuals from coniferous forests from different world regions indicates that European isolates of this fungus should not be used in North America (or vice versa), and, likewise, commercially available eastern North American P. gigantea isolates should not be used in western North America forests. The reported lack of host specificity of P. gigantea was documented by the field survey and further reinforces the need to only use local isolates of this biocontrol fungus, given that genetically distinct exotic genotypes of a broad generalist microbe may easily spread and permanently alter the microbial biodiversity of native forest ecosystems.

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A Linkage-Based Genome Assembly for the Mosquito Aedes albopictus and Identification of Chromosomal Regions Affecting Diapause

Insects ◽

10.3390/insects12020167 ◽

2021 ◽

Vol 12 (2) ◽

pp. 167

Author(s):

John H. Boyle ◽

Pasi M. A. Rastas ◽

Xin Huang ◽

Austin G. Garner ◽

Indra Vythilingam ◽

...

Keyword(s):

Linkage Map ◽

Aedes Albopictus ◽

Dna Sequences ◽

Genome Assembly ◽

Single Copy ◽

Health Concern ◽

Candidate Snps ◽

Single Location ◽

Asian Tiger ◽

Photoperiodic Diapause

The Asian tiger mosquito, Aedes albopictus, is an invasive vector mosquito of substantial public health concern. The large genome size (~1.19–1.28 Gb by cytofluorometric estimates), comprised of ~68% repetitive DNA sequences, has made it difficult to produce a high-quality genome assembly for this species. We constructed a high-density linkage map for Ae. albopictus based on 111,328 informative SNPs obtained by RNAseq. We then performed a linkage-map anchored reassembly of AalbF2, the genome assembly produced by Palatini et al. (2020). Our reassembled genome sequence, AalbF3, represents several improvements relative to AalbF2. First, the size of the AalbF3 assembly is 1.45 Gb, almost half the size of AalbF2. Furthermore, relative to AalbF2, AalbF3 contains a higher proportion of complete and single-copy BUSCO genes (84.3%) and a higher proportion of aligned RNAseq reads that map concordantly to a single location of the genome (46%). We demonstrate the utility of AalbF3 by using it as a reference for a bulk-segregant-based comparative genomics analysis that identifies chromosomal regions with clusters of candidate SNPs putatively associated with photoperiodic diapause, a crucial ecological adaptation underpinning the rapid range expansion and climatic adaptation of A. albopictus.

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Fluorescence in situ hybridization on plant extended chromatin DNA fibers for single-copy and repetitive DNA sequences

Plant Cell Reports ◽

10.1007/s00299-011-1086-y ◽

2011 ◽

Vol 30 (9) ◽

pp. 1779-1786 ◽

Cited By ~ 5

Author(s):

Kun Yang ◽

Hecui Zhang ◽

Richard Converse ◽

Yong Wang ◽

Xiaoying Rong ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Repetitive Dna ◽

Dna Sequences ◽

Single Copy ◽

Repetitive Dna Sequences

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Phylogeny and evolutionary histories of Pyrus L. revealed by phylogenetic trees and networks based on data from multiple DNA sequences

Molecular Phylogenetics and Evolution ◽

10.1016/j.ympev.2014.07.009 ◽

2014 ◽

Vol 80 ◽

pp. 54-65 ◽

Cited By ~ 33

Author(s):

Xiaoyan Zheng ◽

Danying Cai ◽

Daniel Potter ◽

Joseph Postman ◽

Jing Liu ◽

...

Keyword(s):

Dna Sequences ◽

Phylogenetic Trees

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Fossil biogeography: a new model to infer dispersal, extinction and sampling from palaeontological data

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2015.0225 ◽

2016 ◽

Vol 371 (1691) ◽

pp. 20150225 ◽

Cited By ~ 36

Author(s):

Daniele Silvestro ◽

Alexander Zizka ◽

Christine D. Bacon ◽

Borja Cascales-Miñana ◽

Nicolas Salamin ◽

...

Keyword(s):

North America ◽

Fossil Record ◽

Phylogenetic Trees ◽

Phylogenetic Analyses ◽

Historical Biogeography ◽

Extinction Rates ◽

Climatic Cooling ◽

Fossil Data ◽

Incomplete Sampling ◽

Des Model

Methods in historical biogeography have revolutionized our ability to infer the evolution of ancestral geographical ranges from phylogenies of extant taxa, the rates of dispersals, and biotic connectivity among areas. However, extant taxa are likely to provide limited and potentially biased information about past biogeographic processes, due to extinction, asymmetrical dispersals and variable connectivity among areas. Fossil data hold considerable information about past distribution of lineages, but suffer from largely incomplete sampling. Here we present a new dispersal–extinction–sampling (DES) model, which estimates biogeographic parameters using fossil occurrences instead of phylogenetic trees. The model estimates dispersal and extinction rates while explicitly accounting for the incompleteness of the fossil record. Rates can vary between areas and through time, thus providing the opportunity to assess complex scenarios of biogeographic evolution. We implement the DES model in a Bayesian framework and demonstrate through simulations that it can accurately infer all the relevant parameters. We demonstrate the use of our model by analysing the Cenozoic fossil record of land plants and inferring dispersal and extinction rates across Eurasia and North America. Our results show that biogeographic range evolution is not a time-homogeneous process, as assumed in most phylogenetic analyses, but varies through time and between areas. In our empirical assessment, this is shown by the striking predominance of plant dispersals from Eurasia into North America during the Eocene climatic cooling, followed by a shift in the opposite direction, and finally, a balance in biotic interchange since the middle Miocene. We conclude by discussing the potential of fossil-based analyses to test biogeographic hypotheses and improve phylogenetic methods in historical biogeography.

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Diversity of echinostomes (Digenea: Echinostomatidae) in their snail hosts at high latitudes

Parasite ◽

10.1051/parasite/2021054 ◽

2021 ◽

Vol 28 ◽

pp. 59

Author(s):

Camila Pantoja ◽

Anna Faltýnková ◽

Katie O’Dwyer ◽

Damien Jouet ◽

Karl Skírnisson ◽

...

Keyword(s):

North America ◽

Dna Sequences ◽

Sequence Data ◽

Molecular Data ◽

Migratory Bird ◽

Parasite Fauna ◽

Life Cycles ◽

Freshwater Ecosystems ◽

Trematode Species ◽

Host Life

The biodiversity of freshwater ecosystems globally still leaves much to be discovered, not least in the trematode parasite fauna they support. Echinostome trematode parasites have complex, multiple-host life-cycles, often involving migratory bird definitive hosts, thus leading to widespread distributions. Here, we examined the echinostome diversity in freshwater ecosystems at high latitude locations in Iceland, Finland, Ireland and Alaska (USA). We report 14 echinostome species identified morphologically and molecularly from analyses of nad1 and 28S rDNA sequence data. We found echinostomes parasitising snails of 11 species from the families Lymnaeidae, Planorbidae, Physidae and Valvatidae. The number of echinostome species in different hosts did not vary greatly and ranged from one to three species. Of these 14 trematode species, we discovered four species (Echinoparyphium sp. 1, Echinoparyphium sp. 2, Neopetasiger sp. 5, and Echinostomatidae gen. sp.) as novel in Europe; we provide descriptions for the newly recorded species and those not previously associated with DNA sequences. Two species from Iceland (Neopetasiger islandicus and Echinoparyphium sp. 2) were recorded in both Iceland and North America. All species found in Ireland are new records for this country. Via an integrative taxonomic approach taken, both morphological and molecular data are provided for comparison with future studies to elucidate many of the unknown parasite life cycles and transmission routes. Our reports of species distributions spanning Europe and North America highlight the need for parasite biodiversity assessments across large geographical areas.

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