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1.
Ecol Lett ; 27(2): e14377, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361472

RESUMO

Impacts of immigration on micro-evolution and population dynamics fundamentally depend on net rates and forms of resulting gene flow into recipient populations. Yet, the degrees to which observed rates and sex ratios of physical immigration translate into multi-generational genetic legacies have not been explicitly quantified in natural meta-populations, precluding inference on how movements translate into effective gene flow and eco-evolutionary outcomes. Our analyses of three decades of complete song sparrow (Melospiza melodia) pedigree data show that multi-generational genetic contributions from regular natural immigrants substantially exceeded those from contemporary natives, consistent with heterosis-enhanced introgression. However, while contributions from female immigrants exceeded those from female natives by up to three-fold, male immigrants' lineages typically went locally extinct soon after arriving. Both the overall magnitude, and the degree of female bias, of effective gene flow therefore greatly exceeded those which would be inferred from observed physical arrivals, altering multiple eco-evolutionary implications of immigration.


Assuntos
Emigrantes e Imigrantes , Passeriformes , Animais , Masculino , Humanos , Feminino , Fluxo Gênico , Dinâmica Populacional
2.
Mol Genet Genomics ; 299(1): 37, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494535

RESUMO

Identity by descent (IBD) segments, uninterrupted DNA segments derived from the same ancestral chromosomes, are widely used as indicators of relationships in genetics. A great deal of research focuses on IBD segments between related pairs, while the statistical analyses of segments in irrelevant individuals are rare. In this study, we investigated the basic informative features of IBD segments in unrelated pairs in Chinese populations from the 1000 Genome Project. A total of 5922 IBD segments in Chinese interpopulation unrelated individual pairs were detected via IBIS and the average length of IBD was 3.71 Mb in length. It was found that 17.86% of unrelated pairs shared at least one IBD segment in the Chinese cohort. Furthermore, a total of 49 chromosomal regions where IBD segments clustered in high abundance were identified, which might be sharing hotspots in the human genome. Such regions could also be observed in other ancestry populations, which implies that similar IBD backgrounds also exist. Altogether, these results demonstrated the distribution of common background IBD segments, which helps improve the accuracy in pedigree studies based on IBD analysis.


Assuntos
Povo Asiático , Genoma Humano , Humanos , Povo Asiático/genética , Genoma Humano/genética , Linhagem , Projetos de Pesquisa , China
3.
Genet Med ; 26(10): 101210, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39001707

RESUMO

PURPOSE: Fueled by direct-to-consumer (DTC) genetic testing and genetic-relative finder services, some participants in genetic genealogy databases are making "not parent expected" (NPE) discoveries. To better understand experiences of this phenomenon, we surveyed a large cohort of users of genetic relative finder (GRF) services concerning their experiences after an NPE discovery. METHODS: Using thematic analysis, we analyzed responses from a cohort of GRF users (n = 646) to open-ended survey items to understand these experiences and their recommendations for DTC genetic testing companies and other GRF users. RESULTS: We found that individuals had both positive and negative emotional experiences related to the NPE discovery. Positive aspects included deeper self-understanding, connecting with new family members, and uncovering answers to questions. Negative aspects included rejection by new genetic relatives, inability to seek answers from relatives who had already died, and impairment of family relationships, especially with mothers. For many participants, the challenges after the discovery nevertheless felt worthwhile because the truth was uncovered. Perhaps notably, some participants suggested enhanced warnings prediscovery and improved support after discovery from companies who provide DTC genetic testing services. CONCLUSION: GRF services are powerful tools for family research and genealogy. Despite some possible positive and worthwhile experiences arising from making an NPE discovery, GRF users risk dealing with this potentially life-altering experience without adequate support. Participants in this study recommended an increase in resources from DTC genetic testing companies that could help users anticipate and navigate an NPE discovery.


Assuntos
Bases de Dados Genéticas , Triagem e Testes Direto ao Consumidor , Testes Genéticos , Humanos , Feminino , Masculino , Triagem e Testes Direto ao Consumidor/psicologia , Adulto , Pessoa de Meia-Idade , Inquéritos e Questionários , Família/psicologia , Linhagem , Pais/psicologia , Idoso
4.
Mol Phylogenet Evol ; : 108219, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39414098

RESUMO

Stingless bees (tribe Meliponini) are remarkable for their characteristically large social colonies, their capacity to produce honey and other useful products, and their morphological and behavioral diversity. They have a disjunct pan-tropical distribution, primarily occurring in warm and humid environments in the Neotropical, Afrotropical, and Indo-Australasian regions. Even though phylogenetic hypotheses have been proposed for Meliponini based on morphology and molecular data, many questions are still unsolved regarding the evolutionary relationships and systematics of the tribe. In this contribution, we present a large phylogenomic dataset comprising over 2,500 ultra-conserved element (UCE) loci sequenced for 153 species of Meliponini, representing all known genera of stingless bees. The genera Camargoia, Paratrigonoides, Plectoplebeia, Cleptotrigona, Ebaiotrigona, Papuatrigona, Pariotrigona, Platytrigona, and Sahulotrigona were included in molecular phylogenetic analyses for the first time. Concatenated and species-tree analyses were performed using different partitioning strategies and summary methods. We performed gene-genealogy interrogation (GGI) on several recalcitrant nodes to resolve discordances among recovered tree topologies. Results were mostly consistent among analyses, recovering three main lineages of Meliponini congruent with the biogeographic domains to which they are associated. Within major clades, discordances were found in relation to previous works. The genus Frieseomelitta was recovered as paraphyletic in relation to Trichotrigona, and the genus Lepidotrigona was revealed to be composed of two independent lineages. Even though concatenated and weighted ASTRAL analyses were mostly effective in recovering the relationships favored by GGI, they retrieved different results in relation to the phylogenetic placements of Oxytrigona and Cephalotrigona. The most favored hypothesis in GGI analyses was not found in any other analyses, being more congruent with morphological evidence and highlighting the relevance of exploring the support given to alternative hypotheses through topological tests. Recent advances in our capacity to generate molecular sequences from old specimens using modern sequencing methods allowed for unparalleled sampling across genera, yielding a backbone for the phylogenetic relationships of stingless bees, which will further investigations into their systematics and evolution.

5.
Fam Process ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267831

RESUMO

Our clinical experience in psychoanalytic family therapy with families where one member has anorexic symptoms has shown that the therapy space is often invaded by the deathly dimension, by an absence of family historicity, and by a lack of autonomy. These different elements appear as "voids," missing pieces of a family puzzle, and reflect a psychic container damaged by the weight of inherited intergenerational trauma. Rather than disappear, these elements are passed down from one generation to the next, their effects weakening the current group whose psychic envelope develops "holes" and becomes "elastic." This paper will focus on the changes in this psychic container, which shift according to the rhythm of family functioning, oscillating between activation of the deathly toxic function within the group, on the one hand, and tension between the isomorphic and homomorphic mode, on the other. We will show how this clinical identification around the quality of the psychic envelope and its changes is valuable for family therapy.

6.
Mol Biol Evol ; 39(2)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35106601

RESUMO

The evolutionary process of genetic recombination has the potential to rapidly change the properties of a viral pathogen, and its presence is a crucial factor to consider in the development of treatments and vaccines. It can also significantly affect the results of phylogenetic analyses and the inference of evolutionary rates. The detection of recombination from samples of sequencing data is a very challenging problem and is further complicated for SARS-CoV-2 by its relatively slow accumulation of genetic diversity. The extent to which recombination is ongoing for SARS-CoV-2 is not yet resolved. To address this, we use a parsimony-based method to reconstruct possible genealogical histories for samples of SARS-CoV-2 sequences, which enables us to pinpoint specific recombination events that could have generated the data. We propose a statistical framework for disentangling the effects of recurrent mutation from recombination in the history of a sample, and hence provide a way of estimating the probability that ongoing recombination is present. We apply this to samples of sequencing data collected in England and South Africa and find evidence of ongoing recombination.


Assuntos
COVID-19 , SARS-CoV-2 , Genoma Viral , Humanos , Mutação , Filogenia , Recombinação Genética
7.
Annu Rev Genomics Hum Genet ; 21: 535-564, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32289230

RESUMO

In the past few years, cases with DNA evidence that could not be solved with direct matches in DNA databases have benefited from comparing single-nucleotide polymorphism data with private and public genomic databases. Using a combination of genome comparisons and traditional genealogical research, investigators can triangulate distant relatives to the contributor of DNA data from a crime scene, ultimately identifying perpetrators of violent crimes. This approach has also been successful in identifying unknown deceased persons and perpetrators of lesser crimes. Such advances are bringing into focus ethical questions on how much access to DNA databases should be granted to law enforcement and how best to empower public genome contributors with control over their data. The necessary policies will take time to develop but can be informed by reflection on the familial searching policies developed for searches of the federal DNA database and considerations of the anonymity and privacy interests of civilians.


Assuntos
Crime/estatística & dados numéricos , Impressões Digitais de DNA/ética , DNA/genética , Bases de Dados de Ácidos Nucleicos/estatística & dados numéricos , Genética Forense/ética , DNA/análise , Humanos , Linhagem
8.
Hum Genet ; 142(3): 331-341, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36456648

RESUMO

Biological samples containing DNA that is attributed to deceased relatives, can now undergo genetic testing at a reasonable cost due to revolutionary improvements in sampling, sequencing, and analytical techniques. This artifact DNA testing, or 'artDNA', includes genetic analysis of hair locks, stamps, envelopes with saliva traces or teeth. ArtDNA can reveal valuable information about a deceased relative or one's genetic background, but it also presents novel ethical dilemmas and legal uncertainties for genetic researchers and commercial testing services. In this paper, we provide an analysis of some of the unique ethical and legal risks of such testing and provide needed recommendations for practitioners of private family artDNA testing. ArtDNA testing generates ethical and legal risks regarding the privacy and autonomy of deceased individuals, the rights of living relatives over their ancestor's genetic information, and the rights of living persons to control their own genetic information. To mitigate these risks, practitioners can conduct certain preliminary testing to ascertain the identity of a DNA donor and estimate the time that has elapsed postmortem. Generally, the ethical and legal concerns will be higher when a shorter period has passed between the death of the DNA donor and the time of artifact DNA testing. Regardless, all artDNA testing present some risks, and practitioners should exercise professional judgement as necessary.


Assuntos
Artefatos , Testes Genéticos , Humanos , DNA
9.
Electrophoresis ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010138

RESUMO

Genetic genealogy has been more frequently used in forensic investigations in identifying criminals. However, the current genetic genealogy applications usually do not consider lineage markers (including both Y and mitochondrial deoxyribonucleic acid (DNA)), which is probably because not all distant relatives share the same lineage markers. In addition, there is no study to show how to use lineage markers and what methods or thresholds should be applied in genetic genealogy. In this study, we developed a method to quickly determine if two single-nucleotide polymorphism (SNP) profiles are from the same paternal or material lineages by using a mismatch frequency of the SNPs in Y-chromosomal or mitochondrial DNA. For both Y and mitochondrial SNPs, profile pairs from the same or different lineages can be decided with high accuracies (i.e., 0.380% or 0.157% error rates with Y and mitochondrial DNA, respectively). With kinship coefficient filtering based on autosomal SNPs, the accuracies of determining maternal and paternal lineage can be further improved (i.e., 0.120% or 0.057% error rates with Y and mitochondrial DNA, respectively, using a threshold of kinship coefficient >0). This study shows that lineage markers can be very powerful tools with high accuracies to determine lineages, which could help solve cases and reduce costs for genetic genealogy investigations.

10.
Int J Legal Med ; 137(5): 1595-1614, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37341834

RESUMO

Next-generation sequencing (NGS), also known as massively sequencing, enables large dense SNP panel analyses which generate the genetic component of forensic investigative genetic genealogy (FIGG). While the costs of implementing large SNP panel analyses into the laboratory system may seem high and daunting, the benefits of the technology may more than justify the investment. To determine if an infrastructural investment in public laboratories and using large SNP panel analyses would reap substantial benefits to society, a cost-benefit analysis (CBA) was performed. This CBA applied the logic that an increase of DNA profile uploads to a DNA database due to a sheer increase in number of markers and a greater sensitivity of detection afforded with NGS and a higher hit/association rate due to large SNP/kinship resolution and genealogy will increase investigative leads, will be more effective for identifying recidivists which in turn reduces future victims of crime, and will bring greater safety and security to communities. Analyses were performed for worst case/best case scenarios as well as by simulation sampling the range spaces with multiple input values simultaneously to generate best estimate summary statistics. This study shows that the benefits, both tangible and intangible, over the lifetime of an advanced database system would be huge and can be projected to be for less than $1 billion per year (over a 10-year period) investment can reap on average > $4.8 billion in tangible and intangible cost-benefits per year. More importantly, on average > 50,000 individuals need not become victims if FIGG were employed, assuming investigative associations generated were acted upon. The benefit to society is immense making the laboratory investment a nominal cost. The benefits likely are underestimated herein. There is latitude in the estimated costs, and even if they were doubled or tripled, there would still be substantial benefits gained with a FIGG-based approach. While the data used in this CBA are US centric (primarily because data were readily accessible), the model is generalizable and could be used by other jurisdictions to perform relevant and representative CBAs.


Assuntos
Impressões Digitais de DNA , DNA , Humanos , Análise Custo-Benefício , DNA/análise , Sequenciamento de Nucleotídeos em Larga Escala , Crime , Polimorfismo de Nucleotídeo Único
11.
Int J Legal Med ; 137(2): 551-565, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36642749

RESUMO

Informed consent is based on basic ethical principles that should be considered when conducting biomedical and behavioral research involving human subjects. These principles-respect, beneficence, and justice-form the foundations of informed consent which in itself is grounded on three fundamental elements: information, comprehension, and voluntary participation. While informed consent has focused on human subjects and research, the practice has been adopted willingly in the forensic science arena primarily to acquire reference samples from family members to assist in identifying missing persons. With advances in molecular biology technologies, data mining, and access to metadata, it is important to assess whether the past informed consent process and in particular associated risks are concomitant with these increased capabilities. Given the state-of-the-art, areas in which informed consent may need to be modified and augmented are as follows: reference samples from family members in missing persons or unidentified human remains cases; targeted analysis of an individual(s) during forensic genetic genealogy cases to reduce an investigative burden; donors who provide their samples for validation studies (to include population studies and entry into databases that would be applied to forensic statistical calculations) to support implementation of procedures and operations of the forensic laboratory; family members that may contribute samples or obtain genetic information from a molecular autopsy; and use of medical and other acquired samples that could be informative for identification purposes. The informed consent process should cover (1) purpose for collection of samples; (2) process to analyze the samples (to include type of data); (3) benefits (to donor, target, family, community, etc. as applicable); (4) risks (to donor, target, family, community, etc. as applicable); (5) access to data/reports by the donor; (6) sample disposition; (7) removal of data process (i.e., expungement); (8) process to ask questions/assessment of comprehension; (9) follow-up processes; and (10) voluntary, signed, and dated consent. Issues surrounding these topics are discussed with an emphasis on addressing risk factors. Addressing informed consent will allow human subjects to make decisions voluntarily and with autonomy as well as secure the use of samples for intended use.


Assuntos
Compreensão , Consentimento Livre e Esclarecido , Humanos , Projetos de Pesquisa
12.
Demography ; 60(5): 1359-1385, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37680176

RESUMO

Given that surprisingly little is known about the demography of human kinship, we provide a demographic account of the kinship networks of individuals in Sweden in 2017 across sex and cohort between ages 0 and 102. We used administrative register data of the full population of Sweden to provide the first kinship enumeration for a complete population based on empirical data. We created ego-focused kinship networks of children, parents, siblings, grandchildren, grandparents, aunts and uncles, nieces and nephews, and cousins. We show the average number of kin of different types, the distribution of the number of kin, and changes in dispersion over time. A large share of all kin of an individual are horizontal kin, such as cousins. We observe the highest number of kin-on average, roughly 20-around age 35. We show differences between matrilineal and patrilineal kin and differences in the kinship structure arising from fertility with more than one childbearing partner, such as half-siblings. The results demonstrate substantial variability in kinship within a population. We discuss our findings in the context of other methods to estimate kinship.

13.
Proc Natl Acad Sci U S A ; 117(46): 28876-28886, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139566

RESUMO

Genealogical tree modeling is essential for estimating evolutionary parameters in population genetics and phylogenetics. Recent mathematical results concerning ranked genealogies without leaf labels unlock opportunities in the analysis of evolutionary trees. In particular, comparisons between ranked genealogies facilitate the study of evolutionary processes of different organisms sampled at multiple time periods. We propose metrics on ranked tree shapes and ranked genealogies for lineages isochronously and heterochronously sampled. Our proposed tree metrics make it possible to conduct statistical analyses of ranked tree shapes and timed ranked tree shapes or ranked genealogies. Such analyses allow us to assess differences in tree distributions, quantify estimation uncertainty, and summarize tree distributions. We show the utility of our metrics via simulations and an application in infectious diseases.


Assuntos
Genética Populacional/métodos , Análise de Sequência de DNA/métodos , Evolução Biológica , Simulação por Computador , Modelos Genéticos , Linhagem , Filogenia
14.
BMC Biol ; 20(1): 166, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864541

RESUMO

BACKGROUND: Yunnan is located in Southwest China and consists of great cultural, linguistic, and genetic diversity. However, the genomic diversity of ethnic minorities in Yunnan is largely under-investigated. To gain insights into population history and local adaptation of Yunnan minorities, we analyzed 242 whole-exome sequencing data with high coverage (~ 100-150 ×) of Yunnan minorities representing Achang, Jingpo, Dai, and Deang, who were linguistically assumed to be derived from three ancient lineages (the tri-genealogy hypothesis), i.e., Di-Qiang, Bai-Yue, and Bai-Pu. RESULTS: Yunnan minorities show considerable genetic differences. Di-Qiang populations likely migrated from the Tibetan area about 6700 years ago. Genetic divergence between Bai-Yue and Di-Qiang was estimated to be 7000 years, and that between Bai-Yue and Bai-Pu was estimated to be 5500 years. Bai-Pu is relatively isolated, but gene flow from surrounding Di-Qiang and Bai-Yue populations was also found. Furthermore, we identified genetic variants that are differentiated within Yunnan minorities possibly due to the living circumstances and habits. Notably, we found that adaptive variants related to malaria and glucose metabolism suggest the adaptation to thalassemia and G6PD deficiency resulting from malaria resistance in the Dai population. CONCLUSIONS: We provided genetic evidence of the tri-genealogy hypothesis as well as new insights into the genetic history and local adaptation of the Yunnan minorities.


Assuntos
Minorias Étnicas e Raciais , Etnicidade , China/epidemiologia , Etnicidade/genética , Humanos
15.
Trop Anim Health Prod ; 55(5): 292, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37589774

RESUMO

The Romosinuano cattle breed is one of the most important Creole genetic resources in Colombia, and interesting traits like adaptation or reproductive efficiency have promoted its use in different countries in America. To consolidate the genealogical historical records, the review of very first yield records in this population was used to reconstruct the genealogy of the breed since the first animals incorporated to the in vivo germplasm bank and estimate different demographic parameters. The complete genealogy comprises 17,136 animals with 5.8 years of generation interval for two pathways. The estimated average inbreeding for the population and inbred animals was 2.53% and 6.32% respectively, with a progressive increase of inbred animals across the generations. Almost 48% of the total animals presented some level of consanguinity. Effective population size (Ne) based on the inbreeding rate estimated by regression in all generations was 120 animals whereas Ne estimated by equivalent generations was 69 animals. Effective number of founders (Fe), effective number of ancestors (Fa), and ancestors explaining 50% of variability were 75, 48, and 22, respectively. The relation between Fa/Fe of 64% indicates a genetic bottleneck effect in the population studied.


Assuntos
Doenças dos Bovinos , Dermatite , Animais , Bovinos/genética , Colômbia , Aclimatação , Dermatite/veterinária , Endogamia , Fenótipo
16.
J Int Relat Dev (Ljubl) ; : 1-20, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37363284

RESUMO

One of the latest methods being trialled across the development sector to help advance progress towards achievement of the Sustainable Development Goals (SDGs) is 'twinning'. In this equation, twinning is rendered as a broadly replicable methodology for improving development outcomes, with a particular emphasis on building up human resources and technical capacity within governments and national bureaucracies. It is time-bound, target driven and depoliticised. However, the relationship between twinning and development has not always looked this way. Our paper uses a genealogical approach to unpack and illuminate the historical circumstances and politico-economic conditions under which these discourses have previously converged. It documents the gradual historical trajectory of the phenomenon of twinning from an overt political act to a largely apolitical tool of development practitioners. In so doing, it denaturalises the status quo and prompts reflection on alternative pathways, politics and practices of development.

17.
Ber Wiss ; 46(1): 18-37, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36811246

RESUMO

Sheldon Pollock's justly famous work on cosmopolitan orders and processes of vernacularization in the worlds of Latinity and Sanskrit invites questions of a comparative and global-historical character. I will raise such questions in the context of the Persianate cosmopolitan order, especially as exemplified by the early modern Ottoman Empire, focusing on the wave of vernacularizations this empire witnessed in the seventeenth-eighteenth centuries. In this process of vernacularization, new vernacular forms of philological learning appear to have played a crucial role. Building on Bourdieu's work, I will try to analyze the Ottoman cosmopolitan as a pre-modern form of linguistic domination, and vernacularization as a form of resistance. Moving beyond Bourdieu, I will be arguing for a genealogical approach that is alive to premodern non-European philological traditions, and to the historically variable relation between (philological) knowledge and power.


Assuntos
Idioma , Linguística , Império Otomano , Conhecimento
18.
Mol Biol Evol ; 38(3): 1090-1100, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33179746

RESUMO

Incongruence among phylogenetic results has become a common occurrence in analyses of genome-scale data sets. Incongruence originates from uncertainty in underlying evolutionary processes (e.g., incomplete lineage sorting) and from difficulties in determining the best analytical approaches for each situation. To overcome these difficulties, more studies are needed that identify incongruences and demonstrate practical ways to confidently resolve them. Here, we present results of a phylogenomic study based on the analysis 197 taxa and 2,526 ultraconserved element (UCE) loci. We investigate evolutionary relationships of Eucerinae, a diverse subfamily of apid bees (relatives of honey bees and bumble bees) with >1,200 species. We sampled representatives of all tribes within the group and >80% of genera, including two mysterious South American genera, Chilimalopsis and Teratognatha. Initial analysis of the UCE data revealed two conflicting hypotheses for relationships among tribes. To resolve the incongruence, we tested concatenation and species tree approaches and used a variety of additional strategies including locus filtering, partitioned gene-trees searches, and gene-based topological tests. We show that within-locus partitioning improves gene tree and subsequent species-tree estimation, and that this approach, confidently resolves the incongruence observed in our data set. After exploring our proposed analytical strategy on eucerine bees, we validated its efficacy to resolve hard phylogenetic problems by implementing it on a published UCE data set of Adephaga (Insecta: Coleoptera). Our results provide a robust phylogenetic hypothesis for Eucerinae and demonstrate a practical strategy for resolving incongruence in other phylogenomic data sets.


Assuntos
Abelhas/genética , Técnicas Genéticas , Filogenia , Animais , Besouros/genética
19.
Curr Genet ; 68(5-6): 645-659, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36098767

RESUMO

Effectors are secreted by plant-associated microorganisms to modify the host cell physiology. As effectors, the Necrosis- and Ethylene-inducing peptide 1-like proteins (NLPs) are involded in the early phases of plant infection and may trigger host immune responses. Corynespora cassiicola is a polyphagous plant pathogen that causes target spot on many agriculturally important crops. Using genome assembly, gene prediction, and proteome annotation tools, we retrieved 135 NLP-encoding genes from proteomes of 44 isolates. We explored the evolutionary history of NLPs using Bayesian phylogeny, gene genealogies, and selection analyses. We accessed the expression profiles of the NLP genes during the early phase of C. cassiicola-soybean interaction. Three NLP putative-effector genes (Cc_NLP1.1, Cc_NLP1.2A, and Cc_NLP1.2B) were maintained in the genomes of all isolates tested. An NLP putative-non-effector gene (Cc_NLP1.3) was found in three isolates that had been originally obtained from soybean. Putative-effector NLPs were under different selective constraints: Cc_NLP1.1 was under stronger selective pressure, while Cc_NLP1.2A was under a more relaxed constraint. Meanwhile, Cc_NLP1.2B likely evolved under either positive or balancing selection. Despite highly divergent, the putative-effector NLPs maintain conserved the residues necessary to trigger plant immune responses, suggesting they are potentially functional. Only the Cc_NLP1.1 putative-effector gene was significantly expressed at the early hours of soybean colonization, while Cc_NLP1.2A and Cc_NLP1.2B showed much lower levels of gene expression.


Assuntos
Peptídeos , Proteínas , Humanos , Teorema de Bayes , Proteínas/metabolismo , Etilenos , Necrose , Doenças das Plantas/genética
20.
J Math Biol ; 84(6): 51, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35532838

RESUMO

Our goal is to study the genetic composition of a population in which each individual has 2 parents, who contribute equally to the genome of their offspring. We use a biparental Moran model, which is characterized by its fixed number N of individuals. We fix an individual and consider the proportions of the genomes of all individuals living  n time steps later, that come from this individual. When n goes to infinity, these proportions all converge almost surely towards the same random variable. When N then goes to infinity, this random variable multiplied by N (i.e. the stationary weight of any ancestor in the whole population) converges in law towards the mixture of a Dirac measure in 0 and an exponential law with parameter 1/2, and the weights of several given ancestors are independent. This gives an explicit formula for the limiting (deterministic) distribution of all ancestors' weights.


Assuntos
Genoma , Modelos Genéticos , Genética Populacional , Humanos , Linhagem
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