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1.
Heredity (Edinb) ; 130(2): 99-108, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36539450

RESUMO

Dispersal is a critical parameter for successful pest control measures as it determines the rate of movement across target control areas and influences the risk of human exposure. We used a fine-scale spatial population genomic approach to investigate the dispersal ecology and population structure of Aedes notoscriptus, an important disease transmitting mosquito at the Mornington Peninsula, Australia. We sampled and reared Ae. notoscriptus eggs at two time points from 170 traps up to 5 km apart and generated genomic data from 240 individuals. We also produced a draft genome assembly from a laboratory colony established from mosquitoes sampled near the study area. We found low genetic structure (Fst) and high coancestry throughout the study region. Using genetic data to identify close kin dyads, we found that mosquitoes had moved distances of >1 km within a generation, which is further than previously recorded. A spatial autocorrelation analysis of genetic distances indicated genetic similarity at >1 km separation, a tenfold higher distance than for a comparable population of Ae. aegypti, from Cairns, Australia. These findings point to high mobility of Ae. notoscriptus, highlighting challenges of localised intervention strategies. Further sampling within the same area 6 and 12 months after initial sampling showed that egg-counts were relatively consistent across time, and that spatial variation in egg-counts covaried with spatial variation in Wright's neighbourhood size (NS). As NS increases linearly with population density, egg-counts may be useful for estimating relative density in Ae. notoscriptus. The results highlight the importance of acquiring species-specific data when planning control measures.


Assuntos
Aedes , Animais , Humanos , Austrália , População Urbana , Genômica , Densidade Demográfica
2.
Mol Biol Evol ; 37(9): 2568-2583, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32348505

RESUMO

Hybridization between invasive and native species has raised global concern, given the dramatic increase in species range shifts and pest outbreaks due to anthropogenic dispersal. Nevertheless, secondary contact between sister lineages of local and invasive species provides a natural laboratory to understand the factors that determine introgression and the maintenance or loss of species barriers. Here, we characterize the early evolutionary outcomes following secondary contact between invasive Helicoverpa armigera and native H. zea in Brazil. We carried out whole-genome resequencing of Helicoverpa moths from Brazil in two temporal samples: during the outbreak of H. armigera in 2013 and 2017. There is evidence for a burst of hybridization and widespread introgression from local H. zea into invasive H. armigera coinciding with H. armigera expansion in 2013. However, in H. armigera, the admixture proportion and the length of introgressed blocks were significantly reduced between 2013 and 2017, suggesting selection against admixture. In contrast to the genome-wide pattern, there was striking evidence for adaptive introgression of a single region from the invasive H. armigera into local H. zea, including an insecticide resistance allele that increased in frequency over time. In summary, despite extensive gene flow after secondary contact, the species boundaries are largely maintained except for the single introgressed region containing the insecticide-resistant locus. We document the worst-case scenario for an invasive species, in which there are now two pest species instead of one, and the native species has acquired resistance to pyrethroid insecticides through introgression.


Assuntos
Introgressão Genética , Espécies Introduzidas , Mariposas/genética , Adaptação Biológica/genética , Animais , Evolução Biológica , Fluxo Gênico , Genoma de Inseto , Resistência a Inseticidas/genética , Inseticidas , Piretrinas , Simpatria
3.
BMC Genomics ; 20(1): 52, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30651071

RESUMO

BACKGROUND: Insights into the genetic capacities of species to adapt to future climate change can be gained by using comparative genomic and transcriptomic data to reconstruct the genetic changes associated with such adaptations in the past. Here we investigate the genetic changes associated with adaptation to arid environments, specifically climatic extremes and new cactus hosts, through such an analysis of five repleta group Drosophila species. RESULTS: We find disproportionately high rates of gene gains in internal branches in the species' phylogeny where cactus use and subsequently cactus specialisation and high heat and desiccation tolerance evolved. The terminal branch leading to the most heat and desiccation resistant species, Drosophila aldrichi, also shows disproportionately high rates of both gene gains and positive selection. Several Gene Ontology terms related to metabolism were enriched in gene gain events in lineages where cactus use was evolving, while some regulatory and developmental genes were strongly selected in the Drosophila aldrichi branch. Transcriptomic analysis of flies subjected to sublethal heat shocks showed many more downregulation responses to the stress in a heat sensitive versus heat resistant species, confirming the existence of widespread regulatory as well as structural changes in the species' differing adaptations. Gene Ontology terms related to metabolism were enriched in the differentially expressed genes in the resistant species while terms related to stress response were over-represented in the sensitive one. CONCLUSION: Adaptations to new cactus hosts and hot desiccating environments were associated with periods of accelerated evolutionary change in diverse biochemistries. The hundreds of genes involved suggest adaptations of this sort would be difficult to achieve in the timeframes projected for anthropogenic climate change.


Assuntos
Adaptação Fisiológica/genética , Cactaceae/fisiologia , Clima Desértico , Drosophila/genética , Drosophila/fisiologia , Genoma de Inseto , Animais , Análise por Conglomerados , Lógica Fuzzy , Ontologia Genética , Genes de Insetos , Resposta ao Choque Térmico/genética , Anotação de Sequência Molecular , Filogenia , Seleção Genética , Estresse Fisiológico/genética , Transcrição Gênica
4.
J Hered ; 110(1): 80-91, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30445496

RESUMO

We use annotated genomes of 14 Drosophila species covering diverse host use phenotypes to test whether 4 gene families that often have detoxification functions are associated with host shifts among species. Bark, slime flux, flower, and generalist necrotic fruit-feeding species all have similar numbers of carboxyl/cholinesterase, glutathione S-transferase, cytochrome P450, and UDP-glucuronosyltransferase genes. However, species feeding on toxic Morinda citrifolia fruit and the fresh fruit-feeding Drosophila suzukii have about 30 and 60 more, respectively. ABC transporters show a different pattern, with the flower-feeding D. elegans and the generalist necrotic fruit and cactus feeder D. hydei having about 20 and >100 more than the other species, respectively. Surprisingly, despite the complex secondary chemistry we find that 3 cactophilic specialists in the mojavensis species cluster have variably fewer genes than any of the other species across all 4 families. We also find 82 positive selection events across the 4 families, with the terminal D. suzukii and M. citrifolia-feeding D. sechellia branches again having the highest number of such events in proportion to their respective branch lengths. Many of the genes involved in these host-use-specific gene number differences or positive selection events lie in specific clades of the gene families that have been recurrently associated with detoxification. Several genes are also found to be involved in multiple duplication and/or positive selection events across the species studied regardless of their host use phenotypes; the most frequently involved are the ABC transporter CG1718, which is not in a specific clade associated with detoxification, and the α-esterase gene cluster, which is.


Assuntos
Drosophila/genética , Comportamento Alimentar , Genes de Insetos , Animais , Cactaceae , Drosophila/fisiologia , Alimentos/toxicidade , Frutas , Inativação Metabólica
5.
BMC Genomics ; 18(1): 673, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28859620

RESUMO

BACKGROUND: Distinguishing orthologous and paralogous relationships between genes across multiple species is essential for comparative genomic analyses. Various computational approaches have been developed to resolve these evolutionary relationships, but strong trade-offs between precision and recall of orthologue prediction remains an ongoing challenge. RESULTS: Here we present Orthonome, an orthologue prediction pipeline, designed to reduce the trade-off between orthologue capture rates (recall) and accuracy of multi-species orthologue prediction. The pipeline compares sequence domains and then forms sequence-similar clusters before using phylogenetic comparisons to identify inparalogues. It then corrects sequence similarity metrics for fragment and gene length bias using a novel scoring metric capturing relationships between full length as well as fragmented genes. The remaining genes are then brought together for the identification of orthologues within a phylogenetic framework. The orthologue predictions are further calibrated along with inparalogues and gene births, using synteny, to identify novel orthologous relationships. We use 12 high quality Drosophila genomes to show that, compared to other orthologue prediction pipelines, Orthonome provides orthogroups with minimal error but high recall. Furthermore, Orthonome is resilient to suboptimal assembly/annotation quality, with the inclusion of draft genomes from eight additional Drosophila species still providing >6500 1:1 orthologues across all twenty species while retaining a better combination of accuracy and recall than other pipelines. Orthonome is implemented as a searchable database and query tool along with multiple-sequence alignment browsers for all sets of orthologues. The underlying documentation and database are accessible at http://www.orthonome.com . CONCLUSION: We demonstrate that Orthonome provides a superior combination of orthologue capture rates and accuracy on complete and draft drosophilid genomes when tested alongside previously published pipelines. The study also highlights a greater degree of evolutionary conservation across drosophilid species than earlier thought.


Assuntos
Genômica/métodos , Homologia de Sequência do Ácido Nucleico , Animais , Drosophila melanogaster/genética , Evolução Molecular
6.
Mol Ecol ; 24(10): 2423-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25789416

RESUMO

Chromosomal inversion polymorphisms are common in animals and plants, and recent models suggest that alternative arrangements spread by capturing different combinations of alleles acting additively or epistatically to favour local adaptation. It is also thought that inversions typically maintain favoured combinations for a long time by suppressing recombination between alternative chromosomal arrangements. Here, we consider patterns of linkage disequilibrium and genetic divergence in an old inversion polymorphism in Drosophila melanogaster (In(3R)Payne) known to be associated with climate change adaptation and a recent invasion event into Australia. We extracted, karyotyped and sequenced whole chromosomes from two Australian populations, so that changes in the arrangement of the alleles between geographically separated tropical and temperate areas could be compared. Chromosome-wide linkage disequilibrium (LD) analysis revealed strong LD within the region spanned by In(3R)Payne. This genomic region also showed strong differentiation between the tropical and the temperate populations, but no differentiation between different karyotypes from the same population, after controlling for chromosomal arrangement. Patterns of differentiation across the chromosome arm and in gene ontologies were enhanced by the presence of the inversion. These data support the notion that inversions are strongly selected by bringing together combinations of genes, but it is still not clear if such combinations act additively or epistatically. Our data suggest that climatic adaptation through inversions can be dynamic, reflecting changes in the relative abundance of different forms of an inversion and ongoing evolution of allelic content within an inversion.


Assuntos
Adaptação Fisiológica/genética , Inversão Cromossômica , Mudança Climática , Drosophila melanogaster/genética , Genética Populacional , Alelos , Animais , Austrália , Evolução Molecular , Cariótipo , Desequilíbrio de Ligação , Análise de Sequência de DNA
7.
G3 (Bethesda) ; 14(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38564250

RESUMO

Galleria mellonella is a pest of honeybees in many countries because its larvae feed on beeswax. However, G. mellonella larvae can also eat various plastics, including polyethylene, polystyrene, and polypropylene, and therefore, the species is garnering increasing interest as a tool for plastic biodegradation research. This paper presents an improved genome (99.3% completed lepidoptera_odb10 BUSCO; genome mode) for G. mellonella. This 472 Mb genome is in 221 contigs with an N50 of 6.4 Mb and contains 13,604 protein-coding genes. Genes that code for known and putative polyethylene-degrading enzymes and their similarity to proteins found in other Lepidoptera are highlighted. An analysis of secretory proteins more likely to be involved in the plastic catabolic process has also been carried out.


Assuntos
Genoma de Inseto , Mariposas , Animais , Mariposas/genética , Plásticos , Anotação de Sequência Molecular , Biodegradação Ambiental , Genômica/métodos , Padrões de Referência , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
8.
Sci Total Environ ; 926: 171743, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38494020

RESUMO

Per- and poly-fluoroalkyl substances (PFAS) pose a threat to organisms and ecosystems due to their persistent nature. Ecotoxicology endpoints used in regulatory guidelines may not reflect multiple, low-level but persistent stressors. This study examines the biological effects of PFAS on Eastern short-necked turtles in Queensland, Australia. In this study, blood samples were collected and analysed for PFAS, hormone levels, and functional omics endpoints. High levels of PFAS were found in turtles at the impacted site, with PFOS being the dominant constituent. The PFAS profiles of males and females differed, with males having higher PFAS concentrations. Hormone concentrations differed between impacted and reference sites in male turtles, with elevated testosterone and corticosterone indicative of stress. Further, energy utilisation, nucleotide synthesis, nitrogen metabolism, and amino acid synthesis were altered in both male and female turtles from PFAS-impacted sites. Both sexes show similar metabolic responses to environmental stressors from the PFAS-contaminated site, which may adversely affect their reproductive fitness. Purine metabolism, caffeine metabolism, and ferroptosis pathway changes in turtles can cause gout, cell death, and overall health problems. Further, the study showed that prolonged exposure to elevated PFAS levels in the wild could compromise turtle reproductive fitness by disrupting reproductive steroids and metabolic pathways.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Tartarugas , Animais , Masculino , Feminino , Ecossistema , Aptidão Genética , Água Doce , Hormônios , Fluorocarbonos/toxicidade
9.
Mol Ecol ; 22(10): 2716-25, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23506114

RESUMO

In many invertebrates, body size shows genetically based clines, with size increasing in colder climates. Large body size is typically associated with prolonged development times. We consider variation in the CNS-specific gene neurofibromin 1 (Nf1) and its association with body size and development time. We identified two major Nf1 haplotypes in natural populations, Nf1-insertion-A and Nf1-deletion-G. These haplotypes are characterized by a 45-base insertion/deletion (INDEL) in Nf1 intron 2 and an A/G synonymous substitution (locus L17277). Linkage disequilibrium (LD) between the INDEL and adjacent sites is high but appears to be restricted within the Nf1 gene interval. In Australia, the frequency of the Nf1-insertion-A haplotype increases with latitude where wing size is larger, independent of the chromosomal inversion In(3R)Payne. Unexpectedly, the Nf1-insertion-A haplotype is negatively associated with wing size. We found that the Nf1-insertion-A haplotype is enriched in females with shorter development time. This suggests that the Nf1 haplotype cline may be driven by selection for development time rather than size; females from southern (higher latitude) D. melanogaster populations maintain a rapid development time despite being relatively larger, and the higher incidence of Nf1-insertion-A in Southern Australia may contribute to this pattern, whereas the effects of the Nf1 haplotypes on size may be countered by other loci with antagonistic effects on size and development time. Our results point to the potential complexity involved in identifying selection on genetic variants exhibiting pleiotropic effects when studies are based on spatial patterns or association studies.


Assuntos
Tamanho Corporal/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/genética , Neurofibromina 1/genética , Polimorfismo Genético/genética , Seleção Genética , Asas de Animais/anatomia & histologia , Animais , Austrália , Sequência de Bases , Primers do DNA/genética , Drosophila melanogaster/anatomia & histologia , Feminino , Frequência do Gene , Genótipo , Geografia , Haplótipos/genética , Desequilíbrio de Ligação , Dados de Sequência Molecular , Fenótipo , Análise de Sequência de DNA , Fatores de Tempo
10.
Procedia Comput Sci ; 218: 210-219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36743794

RESUMO

COVID-19 is a pandemic that has resulted in numerous fatalities and infections in recent years, with a rising tendency in both the number of infections and deaths and the pace of recovery. Accurate forecasting models are important for making accurate forecasts and taking relevant actions. As a result, accurate short-term forecasting of the number of new cases that are contaminated and recovered is essential for making the best use of the resources at hand and stopping or delaying the spread of such illnesses. This paper shows the various techniques for forecasting the covid-19 cases. This paper classifies the various models according to their category and shows the merits and demerits of various fore-casting techniques. The research provides insight into potential issues that may arise during the forecasting of covid-19 instances for predicting the positive, negative, and death cases in this pandemic. In this paper, numerous forecasting techniques and their categories have been studied. The goal of this work is to aggregate the findings of several forecasting techniques to aid in the fight against the pandemic.

11.
Sci Rep ; 13(1): 660, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635481

RESUMO

The fall armyworm (FAW) Spodoptera frugiperda is thought to have undergone a rapid 'west-to-east' spread since 2016 when it was first identified in western Africa. Between 2018 and 2020, it was recorded from South Asia (SA), Southeast Asia (SEA), East Asia (EA), and Pacific/Australia (PA). Population genomic analyses enabled the understanding of pathways, population sources, and gene flow in this notorious agricultural pest species. Using neutral single nucleotide polymorphic (SNP) DNA markers, we detected genome introgression that suggested most populations in this study were overwhelmingly C- and R-strain hybrids (n = 252/262). SNP and mitochondrial DNA markers identified multiple introductions that were most parsimoniously explained by anthropogenic-assisted spread, i.e., associated with international trade of live/fresh plants and plant products, and involved 'bridgehead populations' in countries to enable successful pest establishment in neighbouring countries. Distinct population genomic signatures between Myanmar and China do not support the 'African origin spread' nor the 'Myanmar source population to China' hypotheses. Significant genetic differentiation between populations from different Australian states supported multiple pathways involving distinct SEA populations. Our study identified Asia as a biosecurity hotspot and a FAW genetic melting pot, and demonstrated the use of genome analysis to disentangle preventable human-assisted pest introductions from unpreventable natural pest spread.


Assuntos
Comércio , Spodoptera , Animais , Ásia , Austrália , Marcadores Genéticos , Spodoptera/genética , Genética Populacional , Fluxo Gênico , Polimorfismo de Nucleotídeo Único , Espécies Introduzidas
12.
Cureus ; 14(6): e25810, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35720780

RESUMO

Coronavirus disease 2019 (COVID-19) has become a worldwide pandemic since the first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was identified in December 2019. Numerous neurological consequences have been reported with COVID-19 infection and its approved vaccines. However, Guillain-Barré syndrome (GBS) is a rare neurological complication associated with COVID-19 infection. This case report describes a 62-year-old female with a three-week history of COVID-19 infection who presented with symmetric polyneuropathy in bilateral lower extremities that progressed to involve bilateral upper extremities and skeletal muscles of respiration, resulting in respiratory distress and necessitating intubation and mechanical ventilation. Cerebrospinal fluid (CSF) analysis revealed albumino-cytologic dissociation, and our patient met the National Institute of Neurological Disorders and Strokes (NINDS) criteria for diagnosing Guillain-Barré Syndrome, making GBS to be the most likely diagnosis. This case report aims to strengthen the association of GBS with COVID-19 infection and describes the hospital course of GBS.

13.
Cureus ; 14(7): e26634, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35949744

RESUMO

In recent decades, the general tendency has switched from the use of tobacco products to the inhalation of marijuana with or without the addition of tobacco. The majority of existing research on marijuana use focuses on its euphoric effects. Pneumothorax, pneumomediastinum, and subcutaneous emphysema are infrequently described in the medical literature in association with cannabis use. It is a diagnostic and therapeutic challenge because of its infrequency of occurrence. We see a huge diversity of multisystem involvement linked with marijuana smoking, and physicians should be aware of this uncommon clinical presentation, which might be observed more often because of the recent upsurge in its consumption. We describe a case of a 20-year-old male with a chronic history of marijuana use disorder who was found to have non-tension type pneumothorax, pneumomediastinum, and subcutaneous emphysema on chest imaging. The patient was managed conservatively and did not require any surgical intervention.

14.
Cureus ; 14(6): e25787, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35832753

RESUMO

Myocarditis is an inflammatory condition that impacts cardiac myocytes and is caused mostly by viruses. It can manifest as chest pain, dyspnea, palpitations, fatigue, syncope, shortness of breath, and in severe cases frank cardiogenic shock. It accounts for around 10 percent of all sudden cardiac deaths in young adults, who are described as being in their early thirties. Inflammatory cardiomyopathy resulting from acute myocarditis may also appear as new-onset heart failure (HF), delaying the diagnosis and treatment of these patients. It is crucial to recognize the sensitivity of symptom onset, especially in young individuals; mildly elevated troponin levels that are inconsistent with the severity of left ventricular ejection fraction (LVEF) impairment and associated left ventricular dilatation strongly suggest inflammatory cardiomyopathy rather than acute myocarditis. The current treatment for myocarditis is primarily supportive, with an emphasis on the management of heart failure and arrhythmias in accordance with clinical practice guidelines. In this case report, we describe a male in his early forties who presented with abrupt onset exertional shortness of breath and chest discomfort. His cardiac catheterization did not show evidence of coronary artery disease; however, an echocardiogram revealed new-onset heart failure with reduced ejection fraction, the diagnosis of coxsackievirus myocarditis was made based on his clinical presentation, and a positive coxsackievirus immunoassay.

15.
Cureus ; 14(12): e32182, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605066

RESUMO

A 69-year-old female with a family history significant for early onset dementia and a past medical history significant for coronary artery disease, primary hypertension, type two diabetes mellitus, and Crohn's disease presents to our facility with rapidly progressive cognitive decline, delusions, hallucinations, and ambulatory dysfunction over the past two months. Neurological examination was remarkable for bilateral horizontal nystagmus, tongue fasciculations, bilateral upper extremity incoordination, and bilateral lower extremity spasticity, atrophy, and weakness. Laboratory and microbiological testing were remarkable for low serum thiamine levels. Computed tomography (CT) of the head without contrast showed significant brain atrophy in the frontal and temporal regions as compared to a CT without contrast of the head 5 years prior. Magnetic resonance imaging (MRI) of the head with and without contrast showed significant atrophy in the frontal and temporal regions as well as the cerebellum. Follow-up electromyography was consistent with lower motor neuron disease. The patient was given adequate thiamine supplementation for her thiamine deficiency and discharged on donepezil with instructions to follow up with the amyotrophic lateral sclerosis clinic for further monitoring and initiation of riluzole.

16.
Cureus ; 14(11): e31613, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36540520

RESUMO

A 48-year-old male presented three days after cocaine use with acute, rapid onset of bilateral lower extremity weakness, bilateral foot numbness, acute urinary retention, and significantly elevated creatinine kinase. Further testing revealed unusual symmetrical edema with contrast enhancement on MRI of the lower extremities. The patient was diagnosed with severe non-traumatic, non-exertional rhabdomyolysis causing lumbosacral plexopathy following cocaine use. The treatment was centered around aggressive fluid resuscitation and electrolyte replacement.

17.
Cureus ; 14(5): e25207, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35747031

RESUMO

In patients with acute coronary syndrome or obstructive coronary artery disease, stents, especially drug-eluting stents (DESs), are used for percutaneous coronary interventions (PCI). DES prevents abrupt closure of the stented artery. Stent thrombosis is an uncommon but serious complication of PCI, especially with the recent advancement of stent technology. We present a case of a 75-year-old male who initially suffered a non-ST segment elevation myocardial infarction (NSTEMI) treated appropriately with PCI and subsequently developed stent thrombosis after 10 days of initial stent placement. He then underwent emergent repeat PCI with successful replacement of stents overlapping previous stents. The patient did well following the procedure. His clopidogrel was changed to a more potent antiplatelet ticagrelor. He remained stable throughout the hospital stay and was discharged home without any further complications following the next 90 days.

18.
Front Genet ; 13: 1012694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386808

RESUMO

The genome of the major agricultural weed species, annual ryegrass (Lolium rigidum) was assembled, annotated and analysed. Annual ryegrass is a major weed in grain cropping, and has the remarkable capacity to evolve resistance to herbicides with various modes of action. The chromosome-level assembly was achieved using short- and long-read sequencing in combination with Hi-C mapping. The assembly size is 2.44 Gb with N50 = 361.79 Mb across 1,764 scaffolds where the seven longest sequences correspond to the seven chromosomes. Genome completeness assessed through BUSCO returned a 99.8% score for complete (unique and duplicated) and fragmented genes using the Viridiplantae set. We found evidence for the expansion of herbicide resistance-related gene families including detoxification genes. The reference genome of L. rigidum is a critical asset for leveraging genetic information for the management of this highly problematic weed species.

19.
Commun Biol ; 5(1): 297, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393491

RESUMO

Native to the Americas, the invasive Spodoptera frugiperda (fall armyworm; FAW) was reported in West Africa in 2016, followed by its chronological detection across the Old World and the hypothesis of an eastward Asia expansion. We explored population genomic signatures of American and Old World FAW and identified 12 maternal mitochondrial DNA genome lineages across the invasive range. 870 high-quality nuclear single nucleotide polymorphic DNA markers identified five distinct New World population clusters, broadly reflecting FAW native geographical ranges and the absence of host-plant preferences. We identified unique admixed Old World populations, and admixed and non-admixed Asian FAW individuals, all of which suggested multiple introductions underpinning the pest's global spread. Directional gene flow from the East into eastern Africa was also detected, in contrast to the west-to-east spread hypothesis. Our study demonstrated the potential of population genomic approaches via international partnership to address global emerging pest threats and biosecurity challenges.


Assuntos
Fluxo Gênico , Metagenômica , Spodoptera , África Oriental , Animais , Ásia , Spodoptera/genética
20.
Mol Ecol Resour ; 22(4): 1559-1581, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34839580

RESUMO

Many Drosophila species differ widely in their distributions and climate niches, making them excellent subjects for evolutionary genomic studies. Here, we have developed a database of high-quality assemblies for 46 Drosophila species and one closely related Zaprionus. Fifteen of the genomes were newly sequenced, and 20 were improved with additional sequencing. New or improved annotations were generated for all 47 species, assisted by new transcriptomes for 19. Phylogenomic analyses of these data resolved several previously ambiguous relationships, especially in the melanogaster species group. However, it also revealed significant phylogenetic incongruence among genes, mainly in the form of incomplete lineage sorting in the subgenus Sophophora but also including asymmetric introgression in the subgenus Drosophila. Using the phylogeny as a framework and taking into account these incongruences, we then screened the data for genome-wide signals of adaptation to different climatic niches. First, phylostratigraphy revealed relatively high rates of recent novel gene gain in three temperate pseudoobscura and five desert-adapted cactophilic mulleri subgroup species. Second, we found differing ratios of nonsynonymous to synonymous substitutions in several hundred orthologues between climate generalists and specialists, with trends for significantly higher ratios for those in tropical and lower ratios for those in temperate-continental specialists respectively than those in the climate generalists. Finally, resequencing natural populations of 13 species revealed tropics-restricted species generally had smaller population sizes, lower genome diversity and more deleterious mutations than the more widespread species. We conclude that adaptation to different climates in the genus Drosophila has been associated with large-scale and multifaceted genomic changes.


Assuntos
Drosophila , Genoma , Adaptação Fisiológica/genética , Animais , Drosophila/genética , Genômica , Humanos , Filogenia
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