scholarly journals A switch to feeding on cycads generates parallel accelerated evolution of toxin tolerance in two clades of Eumaeus caterpillars (Lepidoptera: Lycaenidae)

2021 ◽  
Vol 118 (7) ◽  
pp. e2018965118
Author(s):  
Robert K. Robbins ◽  
Qian Cong ◽  
Jing Zhang ◽  
Jinhui Shen ◽  
Julia Quer Riera ◽  
...  
Keyword(s):  
Parallel Evolution ◽  
The United States ◽  
Genomic Sequences ◽  
Genomic Change ◽  
Gregarious Behavior ◽  
Accelerated Evolution ◽  
History Information ◽  
Close Relatives ◽  
Near Extinction ◽  
Eumaeus Atala

We assembled a complete reference genome of Eumaeus atala, an aposematic cycad-eating hairstreak butterfly that suffered near extinction in the United States in the last century. Based on an analysis of genomic sequences of Eumaeus and 19 representative genera, the closest relatives of Eumaeus are Theorema and Mithras. We report natural history information for Eumaeus, Theorema, and Mithras. Using genomic sequences for each species of Eumaeus, Theorema, and Mithras (and three outgroups), we trace the evolution of cycad feeding, coloration, gregarious behavior, and other traits. The switch to feeding on cycads and to conspicuous coloration was accompanied by little genomic change. Soon after its origin, Eumaeus split into two fast evolving lineages, instead of forming a clump of close relatives in the phylogenetic tree. Significant overlap of the fast evolving proteins in both clades indicates parallel evolution. The functions of the fast evolving proteins suggest that the caterpillars developed tolerance to cycad toxins with a range of mechanisms including autophagy of damaged cells, removal of cell debris by macrophages, and more active cell proliferation.

scholarly journals Early Determinants of Work Disability in an International Perspective

Demography ◽  
2020 ◽  
Vol 57 (5) ◽  
pp. 1853-1879
Author(s):  
Axel Börsch-Supan ◽  
Tabea Bucher-Koenen ◽  
Felizia Hanemann
Keyword(s):  
Work Disability ◽  
Disability Insurance ◽  
The United States ◽  
State Policies ◽  
International Perspective ◽  
Data Set ◽  
International Variation ◽  
Gainful Employment ◽  
Objective Health ◽  
History Information

Abstract This study explores the interrelated roles of health and welfare state policies in the decision to take up disability insurance (DI) benefits due to work disability (WD), defined as the (partial) inability to engage in gainful employment as a result of physical or mental illness. We exploit the large international variation of health, self-reported WD, and the uptake of DI benefits in the United States and Europe using a harmonized data set with life history information assembled from SHARE, ELSA, and HRS. We find that the mismatch between WD and DI benefit receipt varies greatly across countries. Objective health explains a substantial share of the within-country variation in DI, but this is not the case for the variation across countries. Rather, most of the variation between countries and the mismatches are explained by differences in DI policies.

Development of soybean aphid genomic SSR markers using next generation sequencing

Genome ◽  
2011 ◽  
Vol 54 (5) ◽  
pp. 360-367 ◽  
Author(s):  
Tae-Hwan Jun ◽  
Andrew P. Michel ◽  
M.A. Rouf Mian
Keyword(s):  
Molecular Markers ◽  
Next Generation Sequencing ◽  
Ssr Markers ◽  
The United States ◽  
Soybean Aphid ◽  
Genomic Sequences ◽  
Next Generation ◽  
Soybean Aphids ◽  
Genomic Ssr ◽  
Generation Sequencing

Simple sequence repeats (SSRs) or microsatellites are very useful molecular markers, owing to their locus-specific codominant and multiallelic nature, high abundance in the genome, and high rates of transferability across species. The soybean aphid ( Aphis glycines Matsumura) has become the most damaging insect pest of soybean ( Glycine max (L.) Merr.) in North America, since it was first found in the Midwest of the United States in 2000. Biotypes of the soybean aphid capable of colonizing newly developed aphid-resistant soybean cultivars have been recently discovered. Genetic resources, including molecular markers, to study soybean aphids are severely lacking. Recently developed next generation sequencing platforms offer opportunities for high-throughput and inexpensive genome sequencing and rapid marker development. The objectives of this study were (i) to develop and characterize genomic SSR markers from soybean aphid genomic sequences generated by next generation sequencing technology and (ii) to evaluate the utility of the SSRs for genetic diversity or relationship analyses. In total 128 SSR primer pairs were designed from sequences generated by Illumina GAII from a reduced representation library of A. glycines. Nearly 94% (120) of the primer pairs amplified SSR alleles of expected size and 24 SSR loci were polymorphic among three aphid samples from three populations. The polymorphic SSRs were successfully used to differentiate among 24 soybean aphids from Ohio and South Dakota. Sequencing of PCR products of two SSR markers from four aphid samples revealed that the allelic polymorphism was due to variation in the SSR repeats among the aphids. These markers should be particularly useful for genetic differentiation among aphids collected from soybean fields at different localities and regions. These SSR markers provide the soybean aphid research community with the first set of PCR-based codominant markers developed from the genomic sequences of A. glycines.

scholarly journals Origin, Evolution, and Genotyping of Emergent Porcine Epidemic Diarrhea Virus Strains in the United States

mBio ◽  
2013 ◽  
Vol 4 (5) ◽  
Author(s):  
Yao-Wei Huang ◽  
Allan W. Dickerman ◽  
Pablo Piñeyro ◽  
Long Li ◽  
Li Fang ◽  
...  
Keyword(s):  
United States ◽  
Porcine Epidemic Diarrhea Virus ◽  
The United States ◽  
Genomic Sequences ◽  
Evolutionary Divergence ◽  
Origin And Evolution ◽  
Diarrhea Virus ◽  
Porcine Epidemic Diarrhea ◽  
And Control ◽  
Complete Genomic

ABSTRACT Coronaviruses are known to infect humans and other animals and cause respiratory and gastrointestinal diseases. Here we report the emergence of porcine epidemic diarrhea virus (PEDV) in the United States and determination of its origin, evolution, and genotypes based on temporal and geographical evidence. Histological lesions in small intestine sections of affected pigs and the complete genomic sequences of three emergent strains of PEDV isolated from outbreaks in Minnesota and Iowa were characterized. Genetic and phylogenetic analyses of the three U.S. strains revealed a close relationship with Chinese PEDV strains and their likely Chinese origin. The U.S. PEDV strains underwent evolutionary divergence, which can be classified into two sublineages. The three emergent U.S. strains are most closely related to a strain isolated in 2012 from Anhui Province in China, which might be the result of multiple recombination events between different genetic lineages or sublineages of PEDV. Molecular clock analysis of the divergent time based on the complete genomic sequences is consistent with the actual time difference, approximately 2 to 3 years, of the PED outbreaks between China (December 2010) and the United States (May 2013). The finding that the emergent U.S. PEDV strains share unique genetic features at the 5′-untranslated region with a bat coronavirus provided further support of the evolutionary origin of PEDV from bats and potential cross-species transmission. The data from this study have important implications for understanding the ongoing PEDV outbreaks in the United States and will guide future efforts to develop effective preventive and control measures against PEDV. IMPORTANCE The sudden emergence of porcine epidemic diarrhea virus (PEDV), a coronavirus, for the first time in the United States causes significant economic and public health concerns. Since its recognition in May 2013, PEDV has rapidly spread across the United States, resulting in high mortality in piglets in more than 17 States now. The ongoing outbreaks of Middle East respiratory syndrome coronavirus in humans from countries in or near the Arabian Peninsula and the historical deadly nature of the 2002 outbreaks of severe acute respiratory syndrome coronavirus create further anxiety over the emergence of PEDV in the United States due to the lack of scientific information about the origin and evolution of this emerging coronavirus. Here we report the detailed genetic characterization, origin, and evolution of emergent PEDV strains in the United States. The results provide much needed information to devise effective preventive and control strategies against PEDV in the United States.

scholarly journals Molecular Evolution of the Intimin Gene in O111 Clones of Pathogenic Escherichia coli

2002 ◽  
Vol 184 (2) ◽  
pp. 479-487 ◽  
Author(s):  
Cheryl L. Tarr ◽  
Thomas S. Whittam
Keyword(s):  
Escherichia Coli ◽  
Developed Countries ◽  
The United States ◽  
Food Borne ◽  
Pathogenic Escherichia Coli ◽  
Close Relationship ◽  
Important Virulence Factor ◽  
Enterocyte Effacement ◽  
Close Relatives ◽  
Random Substitution

ABSTRACT Intimin is an important virulence factor in two groups of enteric pathogens: enteropathogenic Escherichia coli (EPEC), which is a major cause of infant diarrhea in the developing world, and enterohemorrhagic E. coli (EHEC), which has caused large food-borne outbreaks of hemorrhagic colitis in the United States and other developed countries. Intimin is encoded on a 35-kb pathogenicity island called the locus of enterocyte effacement (LEE). At least five antigenic types have been described for the highly variable gene, and each type is generally characteristic of particular evolutionary lineages. We determined the nucleotide sequences of intimin and other LEE genes in two O111 clones that have not been amenable to typing. The sequences from both O111:H8 and O111:H9 differed from the Int-β that is typical of other clones in the same evolutionary lineage. The sequence from the O111:H8 strains was a mosaic of divergent segments that alternately clustered with Int-α, Int-β, or Int-γ. The sequence from the O111:H9 clone consistently showed a close relationship with that from E2348/69, a distantly related strain that expresses Int-α. The results suggest that there have been multiple acquisitions of the LEE in the EHEC 2/EPEC 2 clonal lineage, with a recent turnover in either O111:H8 or its close relatives. Amino acid substitutions that alter residue charge occurred more frequently than would be expected under random substitution in the extracellular domains of intimin, suggesting that diversifying selection has promoted divergence in this region of the protein. An N-terminal domain that presumably functions in the periplasm may also be under positive selection.

Pax Transatlantica

2021 ◽  
Author(s):  
Jussi M. Hanhimäki
Keyword(s):  
Cold War ◽  
Domestic Politics ◽  
Parallel Evolution ◽  
The United States ◽  
Key Factors ◽  
Third Way ◽  
Transatlantic Relationship ◽  
History Of ◽  
The Cold War ◽  
Third Way Politics

Pax Transatlantica asserts that the recurrent transatlantic crises that have dominated headlines since the end of the Cold War, while not irrelevant, pale when set against the realities of shared interests and goals. It emphasizes three key factors. First, despite inflammatory and dismissive rhetoric, NATO continues to provide a solid security structure for its member states: an institutional framework of a Pax Transatlantica that has stood the test of time by expanding its remit and scope. Second, in a world concerned with the potential effects of trade wars (especially between the United States and China) and the rise of economic nationalism, the transatlantic economic relationship stands apart as the richest, most closely integrated transcontinental economic space on the globe. Third, the book traces the parallel evolution of domestic politics on both sides of the Atlantic with specific focus on the rise of populism. Rather than a sign of transatlantic “drift,” the rise of populism—much like the emergence of so-called Third Way politics on both sides of the Atlantic in the 1990s—is evidence of a closely integrated transatlantic political space. In the end, while it is obvious that the history of the transatlantic relationship—even during the Cold War—was littered with crises, the relationship has endured. Conflicts have illustrated, time and again, the strength of the transatlantic community. The “West,” the book concludes, not only continues to exist. It is likely to thrive in the future.

scholarly journals Rickettsia in the whitefly Bemisia tabaci: Phenotypic variants and fitness effects

2014 ◽  
Author(s):  
Martha S. Hunter ◽  
Einat Zchori-Fein
Keyword(s):  
United States ◽  
Bemisia Tabaci ◽  
Horizontal Transmission ◽  
Critical Role ◽  
Large Change ◽  
The United States ◽  
Bacterial Symbionts ◽  
Fitness Effects ◽  
Accelerated Evolution ◽  
The Usa

The sweet potato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is a major pest of vegetables, field crops, and ornamentals worldwide. This species harbors a diverse assembly of facultative, “secondary” bacterial symbionts, the roles of which are largely unknown. We documented a spectacular sweep of one of these, Rickettsia, in the Southwestern United States in the B biotype (=MEAM1) of B. tabaci, from 1% to 97% over 6 years, as well as a dramatic fitness benefit associated with it in Arizona but not in Israel. Because it is critical to understand the circumstances in which a symbiont invasion can cause such a large change in pest life history, the following objectives were set: 1) Determine the frequency of Rickettsia in B. tabaci in cotton across the United States and Israel. 2) Characterize Rickettsia and B. tabaci genotypes in order to test the hypothesis that genetic variation in either partner is responsible for differences in phenotypes seen in the two countries. 3) Determine the comparative fitness effects of Rickettsia phenotypes in B. tabaci in Israel and the United States. For Obj. 1, a survey of B. tabaci B samples revealed the distribution of Rickettsia across the cotton-growing regions of 13 sites from Israel and 22 sites from the USA. Across the USA, Rickettsia frequencies were heterogeneous among regions, but were generally at frequencies higher than 75% and close to fixation in some areas, whereas in Israel the infection rates were lower and declining. The distinct outcomes of Rickettsia infection in these two countries conform to previouslyreported phenotypic differences. Intermediate frequencies in some areas in both countries may indicate a cost to infection in certain environments or that the frequencies are in flux. This suggests underlying geographic differences in the interactions between bacterial symbionts and the pest. Obj. 2, Sequences of several Rickettsia genes in both locations, including a hypervariableintergenic spacer gene, suggested that the Rickettsia genotype is identical in both countries. Experiments in the US showed that differences in whitefly nuclear genotype had a strong influence on Rickettsia phenotype. Obj. 3. Experiments designed to test for possible horizontal transmission of Rickettsia, showed that these bacteria are transferred from B. tabaci to a plant, moved inside the phloem, and could be acquired by other whiteflies. Plants can serve as a reservoir for horizontal transmission of Rickettsia, a mechanism that may explain the occurrence of phylogenetically-similarsymbionts among unrelated phytophagous insect species. This plant-mediated transmission route may also exist in other insect-symbiont systems, and since symbionts may play a critical role in the ecology and evolution of their hosts, serve as an immediate and powerful tool for accelerated evolution. However, no such horizontal transmission of Rickettsia could be detected in the USA, underlining the difference between the interaction in both countries, or between B. tabaci and the banded wing whitefly on cotton in the USA (Trialeurodes sp. nr. abutiloneus) and the omnivorous bug Nesidiocoristenuis. Additionally, a series of experiments excluded the possibility that Rickettsia is frequently transmitted between B. tabaci and its parasitoid wasps Eretmocerusmundus and Encarsiapergandiella. Lastly, ecological studies on Rickettsia effects on free flight of whiteflies showed no significant influence of symbiont infection on flight. In contrast, a field study of the effects of Rickettsia on whitefly performance on caged cotton in the USA showed strong fitness benefits of infection, and rapid increases in Rickettsia frequency in competition population cages. This result confirmed the benefits to whiteflies of Rickettsia infection in a field setting.

scholarly journals Draft Genomic Sequences of Campylobacter coli Isolates from Chicken Carcasses

2019 ◽  
Vol 8 (28) ◽  
Author(s):  
Aixia Xu ◽  
Aisha Abdul-Wakeel ◽  
Nereus W. Gunther ◽  
Christopher Sommers
Keyword(s):  
United States ◽  
Antibiotic Resistance ◽  
Virulence Factors ◽  
The United States ◽  
Genomic Sequences ◽  
Campylobacter Coli ◽  
Foodborne Illnesses ◽  
Content Type

Campylobacter bacteria are one of the leading causes of bacterial foodborne illnesses in the United States. Here, we report the draft genomic sequences of eight Campylobacter coli isolates from chicken carcasses, including virulence factors and antibiotic resistance.

scholarly journals Molecular convergent and parallel evolution among four high-elevation anuran species from the Tibetan region

BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Bin Lu ◽  
Hong Jin ◽  
Jinzhong Fu
Keyword(s):  
Amino Acid ◽  
Positive Selection ◽  
Convergent Evolution ◽  
Parallel Evolution ◽  
Amino Acid Level ◽  
High Elevation ◽  
Acid Sites ◽  
Anuran Species ◽  
Close Relatives ◽  
Relative Prevalence

Abstract Background To date, evidence for the relative prevalence or rarity of molecular convergent and parallel evolution is conflicting, and understanding of how these processes contribute to adaptation is limited. We compared four high-elevation anuran species (Bufo tibetanus, Nanorana parkeri, Rana kukunoris and Scutiger boulengeri) from the Tibetan region, and examined convergent and parallel amino acid substitutions between them and how they may have contributed to high-elevation adaptation. Results Genomic data of the four high-elevation species and eight of their low-elevation close relatives were gathered. A total of 1098 orthologs shared by all species were identified. We first conducted pairwise comparisons using Zhang and Kumar’s test. Then, the Rconv index was calculated and convergence/divergence correlation plotting was conducted. Furthermore, genes under positive selection and with elevated evolutionary rate were examined. We detected a large number of amino acid sites with convergent or parallel substitutions. Several pairs of high-elevation species, in particular, R. kukunoris vs N. parkeri and B. tibetanus vs S. boulengeri, had excessive amounts of convergent substitutions compared to neutral expectation. Nevertheless, these sites were mostly concentrated in a small number of genes (3–32), and no genome-wide convergence was detected. Furthermore, the majority of these convergent genes were neither under detectable positive selection nor had elevated evolutionary rates, although functional prediction analysis suggested some of the convergent genes could potentially contribute to high-elevation adaptation. Conclusions There is a substantial amount of convergent evolution at the amino-acid level among high-elevation amphibians, although these sites are concentrated in a few genes, not widespread across the genomes. This may attribute to the fact that all the target species are from the same environment. The relative prevalence of convergent substitutions among high-elevation amphibians provides an excellent opportunity for further study of molecular convergent evolution.

“Our Voter Rolls Are Cleaner Than Yours”: Balancing Access and Integrity in Voter List Maintenance

2020 ◽  
Vol 48 (5) ◽  
pp. 560-570
Author(s):  
Thessalia Merivaki
Keyword(s):  
United States ◽  
Local Variation ◽  
The United States ◽  
Demographic Characteristics ◽  
Voter Registration ◽  
Electoral Process ◽  
Election Administration ◽  
History Information ◽  
Registered Voter

Accurate voter lists facilitate access to the electoral process, indicate efficient voter list maintenance, and reinforce electoral integrity. Errors in voter records often result from variation in practices that are difficult to avoid given the decentralized structure of election administration in the United States. In many states, localities lack capacity to efficiently complete voter list maintenance, especially when pressured to keep “clean” voter rolls. I argue that local challenges remain when maintaining voters’ registration and voting history information, which undermines the quality of voter lists and the integrity of the electoral process. I analyze Mississippi’s Statewide Election Management System (SEMS) records and find that voter registration and voting history errors are linked to the county’s active and inactive registered voter rates and demographic characteristics. These findings confirm that local variation in voter list maintenance can impact voters depending on their voter registration status and can result in premature voter list removal.

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