scholarly journals Host-switching by a vertically transmitted rhabdovirus in Drosophila

2011 ◽  
Vol 7 (5) ◽  
pp. 747-750 ◽  
Author(s):  
Ben Longdon ◽  
Lena Wilfert ◽  
Jewelna Osei-Poku ◽  
Heather Cagney ◽  
Darren J. Obbard ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Sequence Data ◽  
Horizontal Transmission ◽  
Virus Infections ◽  
Diverse Range ◽  
Host Fidelity ◽  
Bacterial Endosymbionts ◽  
Host Lineage ◽  
Sigma Virus ◽  
First Time

A diverse range of endosymbionts are found within the cells of animals. As these endosymbionts are normally vertically transmitted, we might expect their evolutionary history to be dominated by host-fidelity and cospeciation with the host. However, studies of bacterial endosymbionts have shown that while this is true for some mutualists, parasites often move horizontally between host lineages over evolutionary timescales. For the first time, to our knowledge, we have investigated whether this is also the case for vertically transmitted viruses. Here, we describe four new sigma viruses, a group of vertically transmitted rhabdoviruses previously known in Drosophila . Using sequence data from these new viruses, and the previously described sigma viruses, we show that they have switched between hosts during their evolutionary history. Our results suggest that sigma virus infections may be short-lived in a given host lineage, so that their long-term persistence relies on rare horizontal transmission events between hosts.

scholarly journals Phylogenomic resolution of scorpions reveals multilevel discordance with morphological phylogenetic signal

2015 ◽  
Vol 282 (1804) ◽  
pp. 20142953 ◽  
Author(s):  
Prashant P. Sharma ◽  
Rosa Fernández ◽  
Lauren A. Esposito ◽  
Edmundo González-Santillán ◽  
Lionel Monod
Keyword(s):  
Fossil Record ◽  
Evolutionary History ◽  
Digestive System ◽  
Sequence Data ◽  
Phylogenetic Signal ◽  
Molecular Sequence Data ◽  
Molecular Sequence ◽  
Single Origin ◽  
As Species ◽  
First Time

Scorpions represent an iconic lineage of arthropods, historically renowned for their unique bauplan, ancient fossil record and venom potency. Yet, higher level relationships of scorpions, based exclusively on morphology, remain virtually untested, and no multilocus molecular phylogeny has been deployed heretofore towards assessing the basal tree topology. We applied a phylogenomic assessment to resolve scorpion phylogeny, for the first time, to our knowledge, sampling extensive molecular sequence data from all superfamilies and examining basal relationships with up to 5025 genes. Analyses of supermatrices as well as species tree approaches converged upon a robust basal topology of scorpions that is entirely at odds with traditional systematics and controverts previous understanding of scorpion evolutionary history. All analyses unanimously support a single origin of katoikogenic development, a form of parental investment wherein embryos are nurtured by direct connections to the parent's digestive system. Based on the phylogeny obtained herein, we propose the following systematic emendations: Caraboctonidae is transferred to Chactoidea new superfamilial assignment ; superfamily Bothriuroidea revalidated is resurrected and Bothriuridae transferred therein; and Chaerilida and Pseudochactida are synonymized with Buthida new parvordinal synonymies .

scholarly journals Integrated Genomic Analyses From Low-Depth Sequencing Help Resolve Phylogenetic Incongruence in the Bamboos (Poaceae: Bambusoideae)

2021 ◽  
Vol 12 ◽  
Author(s):  
Domitille Chalopin ◽  
Lynn G. Clark ◽  
William P. Wysocki ◽  
Minkyu Park ◽  
Melvin R. Duvall ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Sequence Data ◽  
Nuclear Gene ◽  
Genomic Information ◽  
Genomic Tools ◽  
Herbaceous Bamboos ◽  
Genomic Analyses ◽  
Woody Bamboos ◽  
First Time ◽  
Ancient Hybridization

The bamboos (Bambusoideae, Poaceae) comprise a major grass lineage with a complex evolutionary history involving ancient hybridization and allopolyploidy. About 1700 described species are classified into three tribes, Olyreae (herbaceous bamboos), Bambuseae (tropical woody bamboos), and Arundinarieae (temperate woody bamboos). Nuclear analyses strongly support monophyly of the woody tribes, whereas plastome analyses strongly support paraphyly, with Bambuseae sister to Olyreae. Our objectives were to clarify the origin(s) of the woody bamboo tribes and resolve the nuclear vs. plastid conflict using genomic tools. For the first time, plastid and nuclear genomic information from the same bamboo species were combined in a single study. We sampled 51 species of bamboos representing the three tribes, estimated their genome sizes and generated low-depth sample sequence data, from which plastomes were assembled and nuclear repeats were analyzed. The distribution of repeat families was found to agree with nuclear gene phylogenies, but also provides novel insights into nuclear evolutionary history. We infer two early, independent hybridization events, one between an Olyreae ancestor and a woody ancestor giving rise to the two Bambuseae lineages, and another between two woody ancestors giving rise to the Arundinarieae. Retention of the Olyreae plastome associated with differential dominance of nuclear genomes and subsequent diploidization in some lineages explains the paraphyly observed in plastome phylogenetic estimations. We confirm ancient hybridization and allopolyploidy in the origins of the extant woody bamboo lineages and propose biased fractionation and diploidization as important factors in their evolution.

scholarly journals Parasitoids as vectors of facultative bacterial endosymbionts in aphids

2012 ◽  
Vol 8 (4) ◽  
pp. 613-615 ◽  
Author(s):  
Lukas Gehrer ◽  
Christoph Vorburger
Keyword(s):  
Horizontal Transmission ◽  
Aphis Fabae ◽  
Diagnostic Pcr ◽  
Sexual Generation ◽  
Bacterial Endosymbionts ◽  
Symbiont Transmission ◽  
Hamiltonella Defensa ◽  
The Many ◽  
First Time ◽  
Male To Female

Heritable bacterial endosymbionts play an important role in aphid ecology. Sequence-based evidence suggests that facultative symbionts such as Hamiltonella defensa or Regiella insecticola also undergo horizontal transmission. Other than through male-to-female transfer during the sexual generation in autumn, the routes by which this occurs remain largely unknown. Here, we tested if parasitoids or ectoparasitic mites can act as vectors for horizontal transfer of facultative symbionts. Using symbiont-specific primers for diagnostic PCR, we demonstrate for the first time, to our knowledge, that parasitoids can indeed transfer H. defensa and R. insecticola by sequentially stabbing infected and uninfected individuals of their host, Aphis fabae , establishing new, heritable infections. Thus, a natural route of horizontal symbiont transmission is also available during the many clonal generations of the aphid life cycle. No transmissions by ectoparasitic mites were observed, nor did parasitoids that emerged from symbiont-infected aphids transfer any symbionts in our experiments.

scholarly journals ACE2 binding is an ancestral and evolvable trait of sarbecoviruses

2021 ◽  
Author(s):  
Tyler N Starr ◽  
Samantha K Zepeda ◽  
Alexandra C Walls ◽  
Allison J Greaney ◽  
David Veesler ◽  
...  
Keyword(s):  
Amino Acid ◽  
High Throughput ◽  
Evolutionary History ◽  
Single Amino Acid ◽  
Receptor Binding Domain ◽  
Diverse Range ◽  
Ancestral Origin ◽  
History Of ◽  
Amino Acid Mutations ◽  
First Time

Two different sarbecoviruses have caused major human outbreaks in the last two decades. Both these sarbecoviruses, SARS-CoV-1 and SARS-CoV-2, engage ACE2 via the spike receptor-binding domain (RBD). However, binding to ACE2 orthologs from humans, bats, and other species has been observed only sporadically among the broader diversity of bat sarbecoviruses. Here, we use high-throughput assays to trace the evolutionary history of ACE2 binding across a diverse range of sarbecoviruses and ACE2 orthologs. We find that ACE2 binding is an ancestral trait of sarbecovirus RBDs that has subsequently been lost in some clades. Furthermore, we demonstrate for the first time that bat sarbecoviruses from outside Asia can bind ACE2. In addition, ACE2 binding is highly evolvable: for many sarbecovirus RBDs there are single amino-acid mutations that enable binding to new ACE2 orthologs. However, the effects of individual mutations can differ markedly between viruses, as illustrated by the N501Y mutation which enhances human ACE2 binding affinity within several SARS-CoV-2 variants of concern but severely dampens it for SARS-CoV-1. Our results point to the deep ancestral origin and evolutionary plasticity of ACE2 binding, broadening consideration of the range of sarbecoviruses with spillover potential.

Unrivalled Influence

2013 ◽  
Author(s):  
Judith Herrin
Keyword(s):  
Political Life ◽  
General Introduction ◽  
Women And Gender ◽  
Mothers And Daughters ◽  
Diverse Range ◽  
Long Span ◽  
Imperial Court ◽  
And Gender ◽  
The Many ◽  
First Time

This book explores the exceptional roles that women played in the vibrant cultural and political life of medieval Byzantium. This book evokes the complex and exotic world of Byzantium's women, from empresses and saints to uneducated rural widows. Drawing on a diverse range of sources, the book sheds light on the importance of marriage in imperial statecraft, the tense coexistence of empresses in the imperial court, and the critical relationships of mothers and daughters. It looks at women's interactions with eunuchs, the in-between gender in Byzantine society, and shows how women defended their rights to hold land. The book describes how women controlled their inheritances, participated in urban crowds demanding the dismissal of corrupt officials, followed the processions of holy icons and relics, and marked religious feasts with liturgical celebrations, market activity, and holiday pleasures. The vivid portraits that emerge here reveal how women exerted an unrivalled influence on the patriarchal society of Byzantium, and remained active participants in the many changes that occurred throughout the empire's millennial history. The book brings together the author's finest essays on women and gender written throughout the long span of her career. This volume includes three new essays published here for the very first time and a new general introduction. It also provides a concise introduction to each essay that describes how it came to be written and how it fits into her broader views about women and Byzantium.

scholarly journals Phytochemical and Ethnopharmacological Perspectives of Ehretia laevis

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3489
Author(s):  
Pooja Sharma ◽  
Richa Shri ◽  
Fidele Ntie-Kang ◽  
Suresh Kumar
Keyword(s):  
Pentacyclic Triterpenoids ◽  
Diverse Range ◽  
Plant Parts ◽  
Tribal Communities ◽  
Crude Extracts ◽  
Traditional Remedy ◽  
Botanical Description ◽  
Pharmacological Screening ◽  
Therapeutic Activities ◽  
First Time

Ehretia laevis Roxb. (Boraginaceae) has been extensively used as a traditional remedy for the treatment of a diverse range of ailments related to the respiratory system, the gastrointestinal tract, the reproductive system, and against several infections. This review critically assesses and documents, for the first time, the fragmented information on E. laevis, including its botanical description, folklore uses, bioactive phyto metabolites and pharmacological activities. The goal is to explore this plant therapeutically. Ethnomedicinal surveys reveal that E. laevis has been used by tribal communities in Asian countries for the treatment of various disorders. Quantitative and qualitative phytochemical investigations of E. laevis showed the presence of important phytoconstituents such as pentacyclic triterpenoids, phenolic acids, flavonoids, fatty acids, steroids, alkaloids, aliphatic alcohols, hydrocarbons, amino acids, carbohydrates, vitamins and minerals. Fresh plant parts, crude extracts, fractions and isolated compounds have been reported to exhibit broad spectrum of therapeutic activities viz., antioxidant, antiarthritic, antidiabetic, anti-inflammatory, antiulcer, antidiarrheal, antidysenteric, wound healing and anti-infective activities. E. laevis is shown to be an excellent potential source of drugs for the mitigation of jaundice, asthma, dysentery, ulcers, diarrhea, ringworm, eczema, diabetes, fissure, syphilis, cuts and wounds, inflammation, liver problems, venereal and infectious disorders. Although few investigations authenticated its traditional uses but employed uncharacterized crude extracts of the plant, the major concerns raised are reproducibility of therapeutic efficacy and safety of plant material. The outcomes of limited pharmacological screening and reported bioactive compounds of E. laevis suggest that there is an urgent need for in-depth pharmacological investigations of the plant.

scholarly journals Sequences of the second internal transcribed spacer of ribosomal DNA for three species of Trichostrongylus (Nematoda: Trichostrongylidae) from sheep in Russia

2007 ◽  
Vol 44 (2) ◽  
pp. 43-46 ◽  
Author(s):  
D. Kuznetsov ◽  
N. Kuznetsova
Keyword(s):  
Dna Sequence ◽  
Intraspecific Variation ◽  
Ribosomal Dna ◽  
Internal Transcribed Spacer ◽  
Sequence Data ◽  
Moscow Region ◽  
Dna Sequence Data ◽  
Interspecific Differences ◽  
Second Internal Transcribed Spacer ◽  
First Time

AbstractFor the first time, DNA sequence data were obtained for three species of Trichostrongylus from Russia. Internal transcribed spacer (ITS-2) of ribosomal DNA was sequenced for T. axei, T. colubriformis and T. probolurus from sheep from the Moscow region. ITS-2 rDNA length was estimated as 238 nucleotides for T. colubriformis and T. probolurus and 237 nucleotides for T. axei. The G+C content of the ITS-2 sequences of T. colubriformis, T. axei and T. probolurus were 31 %, 32 % and 34 % respectively. The level of interspecific differences in ITS-2 of rDNA of T. axei, T. probolurus and T. colubriformis ranged from 3 to 4 %. The ITS-2 sequences from the Russian specimens were compared with those of T. axei, T. probolurus and T. colubriformis from Australia and Germany. Intraspecific variation ranged from 0 % in T. colubriformis to 3.0 % in T. axei.

Clathrosporium retortum, a novel aeroaquatic fungus in the Sordariomycetidae (Ascomycota) from Brazil

Phytotaxa ◽  
2015 ◽  
Vol 239 (1) ◽  
pp. 17
Author(s):  
Larissa Bernardino Moro ◽  
Gregorio Delgado ◽  
Iracema Helena SCHOENLEIN-CRUSIUS
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Molecular Data ◽  
Sao Paulo ◽  
São Paulo ◽  
Present Fungus ◽  
Broad Concept ◽  
Morphological And Molecular Data ◽  
First Time

Clathrosporium retortum sp. nov., collected on submerged mixed leaf litter samples at Ilha do Cardoso State Park, São Paulo state, Brazil, is described based on morphological and molecular data. The fungus is characterized by forming whitish, dense, subglobose to irregular propagules, hyaline to subhyaline when young, subhyaline to dark brown at maturity, that are formed by densely interwoven conidial filaments with each conidial cell repeatedly branching bilaterally or occasionally unilaterally. Phylogenetic analyses using partial LSU nrDNA sequence data suggest that C. retortum belongs in the Sordariomycetes (Ascomycota) where it forms a well-supported clade with Clohesia corticola in the Sordariomycetidae, but its ordinal or familial placement remains unresolved. Its phylogenetic placement confirms the polyphyletic nature of aeroaquatic fungi like Clathrosporium, as it was distantly related to one available sequence in GenBank named as C. intricatum, the type species, which is phylogenetically related to the Helotiales (Leotiomycetes). However, due to lack of authenticity of the identity of this sequence with the type specimen of C. intricatum, a broad concept of Clathrosporium is tentatively adopted here to accommodate the present fungus instead of introducing a new genus. Beverwykella clathrata, Helicoön septatissimum and Peyronelina glomerulata are recorded for the first time from Brazil. Cancellidium applanatum and Candelabrum brocchiatum are new records for the state of São Paulo.

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