Out of Asia: Mitochondrial evolutionary history of the globally introduced supralittoral isopod Ligia exotica

The native ranges and invasion histories of many marine species remain elusive due to a dynamic dispersal process via marine vessels. Molecular markers can aid in identification of native ranges and elucidation of the introduction and establishment process. The supralittoral isopod Ligia exotica has a wide tropical and subtropical distribution, frequently found in harbors and ports around the globe. This isopod is hypothesized to have an Old World origin, from where it was unintentionally introduced to other regions via wooden ships and solid ballast. Its native range, however, remains uncertain. Recent molecular studies uncovered the presence of two highly divergent lineages of L. exotica in East Asia, and suggest this region is a source of nonindigenous populations. In this study, we conducted phylogenetic analyses (Maximum Likelihood and Bayesian) of a fragment of the mitochondrial 16S ribosomal (r)DNA gene using a dataset of this isopod that greatly expanded previous representation from Asia and putative nonindigenous populations around the world. For a subset of samples, sequences of 12S rDNA and NaK were also obtained and analyzed together with 16S rDNA. Our results show that L. exotica is comprised of several highly divergent genetic lineages, which probably represent different species. Most of the 16S rDNA genetic diversity (48 haplotypes) was detected in East and Southeast Asia. Only seven haplotypes were observed outside this region (in the Americas, Hawai’i, Africa and India), which were identical or closely related to haplotypes found in East and Southeast Asia. Phylogenetic patterns indicate the L. exotica clade originated and diversified in East and Southeast Asia, and only members of one of the divergent lineages have spread out of this region, recently, suggesting the potential to become invasive is phylogenetically constrained.

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Out of Asia: mitochondrial evolutionary history of the globally introduced supralittoral isopodLigia exotica

PeerJ ◽

10.7717/peerj.4337 ◽

2018 ◽

Vol 6 ◽

pp. e4337 ◽

Cited By ~ 3

Author(s):

Luis A. Hurtado ◽

Mariana Mateos ◽

Chang Wang ◽

Carlos A. Santamaria ◽

Jongwoo Jung ◽

...

Keyword(s):

Southeast Asia ◽

16S Rdna ◽

Evolutionary History ◽

Phylogenetic Analyses ◽

Marine Species ◽

Genetic Lineages ◽

East And Southeast Asia ◽

History Of ◽

Marine Vessels ◽

Establishment Process

The native ranges and invasion histories of many marine species remain elusive due to a dynamic dispersal process via marine vessels. Molecular markers can aid in identification of native ranges and elucidation of the introduction and establishment process. The supralittoral isopodLigia exoticahas a wide tropical and subtropical distribution, frequently found in harbors and ports around the globe. This isopod is hypothesized to have an Old World origin, from where it was unintentionally introduced to other regions via wooden ships and solid ballast. Its native range, however, remains uncertain. Recent molecular studies uncovered the presence of two highly divergent lineages ofL. exoticain East Asia, and suggest this region is a source of nonindigenous populations. In this study, we conducted phylogenetic analyses (Maximum Likelihood and Bayesian) of a fragment of the mitochondrial 16S ribosomal (r)DNA gene using a dataset of this isopod that greatly expanded previous representation from Asia and putative nonindigenous populations around the world. For a subset of samples, sequences of 12S rDNA and NaK were also obtained and analyzed together with 16S rDNA. Our results show thatL. exoticais comprised of several highly divergent genetic lineages, which probably represent different species. Most of the 16S rDNA genetic diversity (48 haplotypes) was detected in East and Southeast Asia. Only seven haplotypes were observed outside this region (in the Americas, Hawai’i, Africa and India), which were identical or closely related to haplotypes found in East and Southeast Asia. Phylogenetic patterns indicate theL. exoticaclade originated and diversified in East and Southeast Asia, and only members of one of the divergent lineages have spread out of this region, recently, suggesting the potential to become invasive is phylogenetically constrained.

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Out of Asia: Mitochondrial evolutionary history of the globally introduced supralittoral isopod Ligia exotica

10.7287/peerj.preprints.3497 ◽

2017 ◽

Author(s):

Luis A Hurtado ◽

Mariana Mateos ◽

Chang Wang ◽

Carlos A Santamaria ◽

Jongwoo Jung ◽

...

Keyword(s):

Southeast Asia ◽

16S Rdna ◽

Evolutionary History ◽

Phylogenetic Analyses ◽

Marine Species ◽

Genetic Lineages ◽

East And Southeast Asia ◽

History Of ◽

Marine Vessels ◽

Establishment Process

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Evolutionary history of the mtDNA 9-bp deletion in Chinese populations and its relevance to the peopling of east and southeast Asia

Human Genetics ◽

10.1007/s004390000403 ◽

2000 ◽

Vol 107 (5) ◽

pp. 504-512 ◽

Cited By ~ 37

Author(s):

Yong-Gang Yao ◽

W. Watkins ◽

Ya-Ping Zhang

Keyword(s):

Southeast Asia ◽

Evolutionary History ◽

Chinese Populations ◽

East And Southeast Asia ◽

History Of

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Nephromyces represents a diverse and novel lineage of the Apicomplexa that has retained apicoplasts

Genome Biology and Evolution ◽

10.1093/gbe/evz155 ◽

2019 ◽

Cited By ~ 4

Author(s):

Sergio A Muñoz-Gómez ◽

Keira Durnin ◽

Laura Eme ◽

Christopher Paight ◽

Christopher E Lane ◽

...

Keyword(s):

Life Style ◽

Metabolic Pathways ◽

Evolutionary History ◽

Phylogenetic Analyses ◽

Phylogenetic Position ◽

Biosynthetic Pathways ◽

History Of ◽

Sea Squirts ◽

Shed Light ◽

Apicoplast Genome

Abstract A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to (1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, (2) search for the apicoplast genome of Nephromyces, and (3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the non-photosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.

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Archipelago colonization by ecologically dissimilar amphibians: Evaluating the expectation of common evolutionary history of geographical diffusion in co-distributed rainforest tree frogs in islands of Southeast Asia

Molecular Phylogenetics and Evolution ◽

10.1016/j.ympev.2013.12.006 ◽

2014 ◽

Vol 72 ◽

pp. 35-41 ◽

Cited By ~ 6

Author(s):

Paulette Gonzalez ◽

Yong-Chao Su ◽

Cameron D. Siler ◽

Anthony J. Barley ◽

Marites B. Sanguila ◽

...

Keyword(s):

Southeast Asia ◽

Evolutionary History ◽

History Of ◽

Tree Frogs

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A test statistic to quantify treelikeness in phylogenetics

10.1101/2021.02.16.431544 ◽

2021 ◽

Author(s):

Caitlin Cherryh ◽

Bui Quang Minh ◽

Rob Lanfear

Keyword(s):

Evolutionary History ◽

Incomplete Lineage Sorting ◽

Phylogenetic Analyses ◽

Phylogenetic Network ◽

Parametric Bootstrap ◽

Lineage Sorting ◽

Test Statistic ◽

Sequence Alignments ◽

Wide Range ◽

History Of

AbstractMost phylogenetic analyses assume that the evolutionary history of an alignment (either that of a single locus, or of multiple concatenated loci) can be described by a single bifurcating tree, the so-called the treelikeness assumption. Treelikeness can be violated by biological events such as recombination, introgression, or incomplete lineage sorting, and by systematic errors in phylogenetic analyses. The incorrect assumption of treelikeness may then mislead phylogenetic inferences. To quantify and test for treelikeness in alignments, we develop a test statistic which we call the tree proportion. This statistic quantifies the proportion of the edge weights in a phylogenetic network that are represented in a bifurcating phylogenetic tree of the same alignment. We extend this statistic to a statistical test of treelikeness using a parametric bootstrap. We use extensive simulations to compare tree proportion to a range of related approaches. We show that tree proportion successfully identifies non-treelikeness in a wide range of simulation scenarios, and discuss its strengths and weaknesses compared to other approaches. The power of the tree-proportion test to reject non-treelike alignments can be lower than some other approaches, but these approaches tend to be limited in their scope and/or the ease with which they can be interpreted. Our recommendation is to test treelikeness of sequence alignments with both tree proportion and mosaic methods such as 3Seq. The scripts necessary to replicate this study are available at https://github.com/caitlinch/treelikeness

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Adaptive convergent evolution of genome proofreading in SARS-CoV2: insights into the Eigen’s paradox

10.1101/2021.09.11.459886 ◽

2021 ◽

Author(s):

Keerthic Aswin ◽

Srinivasan Ramachandran ◽

Vivek T Natarajan

Keyword(s):

Convergent Evolution ◽

Genome Stability ◽

Evolutionary History ◽

Rna Binding ◽

Phylogenetic Analyses ◽

Comparative Genome Analysis ◽

The Family ◽

History Of ◽

Key Residues

AbstractEvolutionary history of coronaviruses holds the key to understand mutational behavior and prepare for possible future outbreaks. By performing comparative genome analysis of nidovirales that contain the family of coronaviruses, we traced the origin of proofreading, surprisingly to the eukaryotic antiviral component ZNFX1. This common recent ancestor contributes two zinc finger (ZnF) motifs that are unique to viral exonuclease, segregating them from DNA proof-readers. Phylogenetic analyses indicate that following acquisition, genomes of coronaviruses retained and further fine-tuned proofreading exonuclease, whereas related families harbor substitution of key residues in ZnF1 motif concomitant to a reduction in their genome sizes. Structural modelling followed by simulation suggests the role of ZnF in RNA binding. Key ZnF residues strongly coevolve with replicase, and the helicase involved in duplex RNA unwinding. Hence, fidelity of replication in coronaviruses is a result of convergent evolution, that enables maintenance of genome stability akin to cellular proofreading systems.

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Genomic signatures of G-protein-coupled receptor expansions reveal functional transitions in the evolution of cephalopod signal transduction

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.2929 ◽

2019 ◽

Vol 286 (1897) ◽

pp. 20182929 ◽

Cited By ~ 2

Author(s):

Elena A. Ritschard ◽

Robert R. Fitak ◽

Oleg Simakov ◽

Sönke Johnsen

Keyword(s):

Signal Transduction ◽

Positive Selection ◽

G Protein ◽

Evolutionary History ◽

Expression Profiles ◽

Phylogenetic Analyses ◽

Expression Patterns ◽

Genomic Signatures ◽

History Of ◽

G Protein Coupled

Coleoid cephalopods show unique morphological and neural novelties, such as arms with tactile and chemosensory suckers and a large complex nervous system. The evolution of such cephalopod novelties has been attributed at a genomic level to independent gene family expansions, yet the exact association and the evolutionary timing remain unclear. In the octopus genome, one such expansion occurred in the G-protein-coupled receptors (GPCRs) repertoire, a superfamily of proteins that mediate signal transduction. Here, we assessed the evolutionary history of this expansion and its relationship with cephalopod novelties. Using phylogenetic analyses, at least two cephalopod- and two octopus-specific GPCR expansions were identified. Signatures of positive selection were analysed within the four groups, and the locations of these sequences in the Octopus bimaculoides genome were inspected. Additionally, the expression profiles of cephalopod GPCRs across various tissues were extracted from available transcriptomic data. Our results reveal the evolutionary history of cephalopod GPCRs. Unexpanded cephalopod GPCRs shared with other bilaterians were found to be mainly nervous tissue specific. By contrast, duplications that are shared between octopus and the bobtail squid or specific to the octopus' lineage generated copies with divergent expression patterns devoted to tissues outside of the brain. The acquisition of novel expression domains was accompanied by gene order rearrangement through either translocation or duplication and gene loss. Lastly, expansions showed signs of positive selection and some were found to form tandem clusters with shared conserved expression profiles in cephalopod innovations such as the axial nerve cord. Altogether, our results contribute to the understanding of the molecular and evolutionary history of signal transduction and provide insights into the role of this expansion during the emergence of cephalopod novelties and/or adaptations.

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There and back again: What the Cold War for Southeast Asia can teach us about Sino-US competition in the region today

International Journal Canada s Journal of Global Policy Analysis ◽

10.1177/0020702019855352 ◽

2019 ◽

Vol 74 (2) ◽

pp. 301-312

Author(s):

Wen-Qing Ngoei

Keyword(s):

Cold War ◽

Southeast Asia ◽

Foreign Relations ◽

Critical Role ◽

The United States ◽

The Us ◽

East And Southeast Asia ◽

History Of ◽

Expert Commentary ◽

The Cold War

This essay examines how the history of the Cold War in Southeast Asia has shaped, and will likely continue to shape, the current Sino-US rivalry in the region. Expert commentary today typically focuses on the agendas and actions of the two big powers, the United States and China, which actually risks missing the bigger picture. During the Cold War, leaders of ASEAN (Association of Southeast Asian Nations) played a critical role in containing Chinese influence, shaping the terms of Sino-US competition and rapprochement, and deepening the US presence in Southeast Asia. The legacy of ASEAN’s foreign relations during and since the Cold War imposes constraints on Chinese regional ambitions today, which militates against the popular notion that Chinese hegemony in East and Southeast Asia is inevitable. This essay underscores that current analyses of the brewing crisis in and around the South China Sea must routinely look beyond the two superpowers to the under-appreciated agency of small- and middle-sized ASEAN actors who, in reality, are the ones who hold the fate of the region in their hands.

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