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1.
Nat Immunol ; 17(5): 514-522, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27043414

RESUMO

Cytosolic DNA-mediated activation of the transcription factor IRF3 is a key event in host antiviral responses. Here we found that infection with DNA viruses induced interaction of the metabolic checkpoint kinase mTOR downstream effector and kinase S6K1 and the signaling adaptor STING in a manner dependent on the DNA sensor cGAS. We further demonstrated that the kinase domain, but not the kinase function, of S6K1 was required for the S6K1-STING interaction and that the TBK1 critically promoted this process. The formation of a tripartite S6K1-STING-TBK1 complex was necessary for the activation of IRF3, and disruption of this signaling axis impaired the early-phase expression of IRF3 target genes and the induction of T cell responses and mucosal antiviral immunity. Thus, our results have uncovered a fundamental regulatory mechanism for the activation of IRF3 in the cytosolic DNA pathway.


Assuntos
DNA/imunologia , Fator Regulador 3 de Interferon/imunologia , Proteínas de Membrana/imunologia , Proteínas Quinases S6 Ribossômicas 90-kDa/imunologia , Adenoviridae/genética , Adenoviridae/imunologia , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Citosol/imunologia , Citosol/metabolismo , Citosol/virologia , DNA/genética , DNA/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células HEK293 , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/fisiologia , Humanos , Imunização/métodos , Immunoblotting , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotidiltransferases/genética , Nucleotidiltransferases/imunologia , Nucleotidiltransferases/metabolismo , Ovalbumina/genética , Ovalbumina/imunologia , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo
2.
Nature ; 609(7927): 552-559, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045292

RESUMO

Prostate cancer is characterized by considerable geo-ethnic disparity. African ancestry is a significant risk factor, with mortality rates across sub-Saharan Africa of 2.7-fold higher than global averages1. The contributing genetic and non-genetic factors, and associated mutational processes, are unknown2,3. Here, through whole-genome sequencing of treatment-naive prostate cancer samples from 183 ancestrally (African versus European) and globally distinct patients, we generate a large cancer genomics resource for sub-Saharan Africa, identifying around 2 million somatic variants. Significant African-ancestry-specific findings include an elevated tumour mutational burden, increased percentage of genome alteration, a greater number of predicted damaging mutations and a higher total of mutational signatures, and the driver genes NCOA2, STK19, DDX11L1, PCAT1 and SETBP1. Examining all somatic mutational types, we describe a molecular taxonomy for prostate cancer differentiated by ancestry and defined as global mutational subtypes (GMS). By further including Chinese Asian data, we confirm that GMS-B (copy-number gain) and GMS-D (mutationally noisy) are specific to African populations, GMS-A (mutationally quiet) is universal (all ethnicities) and the African-European-restricted subtype GMS-C (copy-number losses) predicts poor clinical outcomes. In addition to the clinical benefit of including individuals of African ancestry, our GMS subtypes reveal different evolutionary trajectories and mutational processes suggesting that both common genetic and environmental factors contribute to the disparity between ethnicities. Analogous to gene-environment interaction-defined here as a different effect of an environmental surrounding in people with different ancestries or vice versa-we anticipate that GMS subtypes act as a proxy for intrinsic and extrinsic mutational processes in cancers, promoting global inclusion in landmark studies.


Assuntos
População Negra , Neoplasias da Próstata , África/etnologia , África Subsaariana/etnologia , Povo Asiático/genética , População Negra/genética , Proteínas de Transporte/genética , China/etnologia , Etnicidade/genética , Europa (Continente)/etnologia , Humanos , Masculino , Mutação , Proteínas Nucleares/genética , Coativador 2 de Receptor Nuclear/genética , Neoplasias da Próstata/genética , RNA Helicases/genética , RNA Longo não Codificante/genética
3.
Nature ; 575(7781): 185-189, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659339

RESUMO

Anatomically modern humans originated in Africa around 200 thousand years ago (ka)1-4. Although some of the oldest skeletal remains suggest an eastern African origin2, southern Africa is home to contemporary populations that represent the earliest branch of human genetic phylogeny5,6. Here we generate, to our knowledge, the largest resource for the poorly represented and deepest-rooting maternal L0 mitochondrial DNA branch (198 new mitogenomes for a total of 1,217 mitogenomes) from contemporary southern Africans and show the geographical isolation of L0d1'2, L0k and L0g KhoeSan descendants south of the Zambezi river in Africa. By establishing mitogenomic timelines, frequencies and dispersals, we show that the L0 lineage emerged within the residual Makgadikgadi-Okavango palaeo-wetland of southern Africa7, approximately 200 ka (95% confidence interval, 240-165 ka). Genetic divergence points to a sustained 70,000-year-long existence of the L0 lineage before an out-of-homeland northeast-southwest dispersal between 130 and 110 ka. Palaeo-climate proxy and model data suggest that increased humidity opened green corridors, first to the northeast then to the southwest. Subsequent drying of the homeland corresponds to a sustained effective population size (L0k), whereas wet-dry cycles and probable adaptation to marine foraging allowed the southwestern migrants to achieve population growth (L0d1'2), as supported by extensive south-coastal archaeological evidence8-10. Taken together, we propose a southern African origin of anatomically modern humans with sustained homeland occupation before the first migrations of people that appear to have been driven by regional climate changes.


Assuntos
População Negra , Migração Humana/história , Filogenia , Áreas Alagadas , População Negra/genética , População Negra/história , Clima , DNA Mitocondrial , Genoma Mitocondrial/genética , Haplótipos , História Antiga , Humanos , Densidade Demográfica , Chuva , Estações do Ano , África do Sul
4.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32379294

RESUMO

Somatic structural variants (SVs), which are variants that typically impact >50 nucleotides, play a significant role in cancer development and evolution but are notoriously more difficult to detect than small variants from short-read next-generation sequencing (NGS) data. This is due to a combination of challenges attributed to the purity of tumour samples, tumour heterogeneity, limitations of short-read information from NGS and sequence alignment ambiguities. In spite of active development of SV detection tools (callers) over the past few years, each method has inherent advantages and limitations. In this review, we highlight some of the important factors affecting somatic SV detection and compared the performance of seven commonly used SV callers. In particular, we focus on the extent of change in sensitivity and precision for detecting different SV types and size ranges from samples with differing variant allele frequencies and sequencing depths of coverage. We highlight the reasons for why some SV callers perform well in some settings but not others, allowing our evaluation findings to be extended beyond the seven SV callers examined in this paper. As the importance of large SVs become increasingly recognized in cancer genomics, this paper provides a timely review on some of the most impactful factors influencing somatic SV detection that should be considered when choosing SV callers.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias/genética , Frequência do Gene , Variação Genética , Humanos , Neoplasias/patologia , Análise de Sequência de DNA/métodos
6.
Genome Res ; 28(5): 726-738, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29618486

RESUMO

Genomic rearrangements are common in cancer, with demonstrated links to disease progression and treatment response. These rearrangements can be complex, resulting in fusions of multiple chromosomal fragments and generation of derivative chromosomes. Although methods exist for detecting individual fusions, they are generally unable to reconstruct complex chained events. To overcome these limitations, we adopted a new optical mapping approach, allowing megabase-length genome maps to be reconstructed and rearranged genomes to be visualized without loss of integrity. Whole-genome mapping (Bionano Genomics) of a well-studied highly rearranged liposarcoma cell line resulted in 3338 assembled consensus genome maps, including 72 fusion maps. These fusion maps represent 112.3 Mb of highly rearranged genomic regions, illuminating the complex architecture of chained fusions, including content, order, orientation, and size. Spanning the junction of 147 chromosomal translocations, we found a total of 28 Mb of interspersed sequences that could not be aligned to the reference genome. Traversing these interspersed sequences using short-read sequencing breakpoint calls, we were able to identify and place 399 sequencing fragments within the optical mapping gaps, thus illustrating the complementary nature of optical mapping and short-read sequencing. We demonstrate that optical mapping provides a powerful new approach for capturing a higher level of complex genomic architecture, creating a scaffold for renewed interpretation of sequencing data of particular relevance to human cancer.


Assuntos
Mapeamento Cromossômico/métodos , Variação Genética , Genoma Humano/genética , Neoplasias/genética , Linhagem Celular Tumoral , Aberrações Cromossômicas , Fusão Gênica , Rearranjo Gênico , Haplótipos , Humanos , Modelos Genéticos , Análise de Sequência de DNA/métodos
7.
J Clin Densitom ; 22(1): 52-58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29111198

RESUMO

This study aims to quantitatively evaluate the cumulative effective dose and associated cancer risk of pediatric patients of US and Hong Kong population undergoing repetitive whole-body scans with dual-energy X-ray absorptiometry (DXA) during their diagnosis and follow-up periods. Organ-absorbed doses of pediatric patients undergoing DXA whole-body scan have been computer simulated using patient imaging parameters input to the Monte Carlo software PCXMC. Gender- and age-specific effective doses have been calculated with the simulated organ-absorbed doses using the ICRP-103 approach. The associated radiation-induced cancer risk, expressed as lifetime attributable cancer risk (LAR), has been estimated according to the method introduced in the Biological Effects of Ionizing Radiation VII report. Mathematical fitting for effective dose and for LAR, as a function of age at exposure, has been analytically obtained to quantitatively estimate the cumulated effective dose and LAR for pediatric patients of US and Hong Kong population with repetitive DXA whole-body scan during their follow-up period. The effective dose of a single DXA whole-body scan for patients exposed at the age between 5 and 18 years was calculated as 8.47-17.68 µSv. The corresponding LAR for US and Hong Kong population was between the range of 4.57 × 10-7 and 7.14 × 10-7. The cumulative effective dose of DXA whole-body scan for patients exposed annually at age between 5 and 18 years was calculated as 180 µSv for girls and 168 µSv for boys. The corresponding cumulative LAR for US and Hong Kong population was calculated as 3.77 × 10-6 to 5.48 × 10-6. Girls would be at a statistically significant higher cumulated cancer risk than boys under the same whole-body DXA protocol (p = 0.03). The probability of cumulative LAR for pediatric populations undergoing annual DXA whole-body scan is regarded as minimal. We demonstrate the use of computer simulation and analytic formulation to quantitatively obtain the cumulated effective dose and cancer risk at any age of exposure, which are useful information for medical personnel to track patient radiation dose and to alleviate patients' parents concern about radiation safety in repetitive whole-body scan using DXA.


Assuntos
Absorciometria de Fóton , Neoplasias Induzidas por Radiação/epidemiologia , Doses de Radiação , Irradiação Corporal Total , Adolescente , Criança , Pré-Escolar , Simulação por Computador , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Método de Monte Carlo , Medição de Risco , Estados Unidos/epidemiologia
8.
Prostate ; 78(1): 25-31, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29134670

RESUMO

BACKGROUND: Mitochondrial genome (mtDNA) content is depleted in many cancers. In prostate cancer, there is intra-glandular as well as inter-patient mtDNA copy number variation. In this study, we determine if mtDNA content can be used as a predictor for prostate cancer staging and outcomes. METHODS: Fresh prostate cancer biopsies from 115 patients were obtained at time of surgery. All cores underwent pathological review, followed by isolation of cancer and normal tissue. DNA was extracted and qPCR performed to quantify the total amount of mtDNA as a ratio to genomic DNA. Differences in mtDNA content were compared for prostate cancer pathology features and disease outcomes. RESULTS: We showed a significantly reduced mtDNA content in prostate cancer compared with normal adjacent prostate tissue (mean difference 1.73-fold, P-value <0.001). Prostate cancer with increased mtDNA content showed unfavorable pathologic characteristics including, higher disease stage (PT2 vs PT3 P-value = 0.018), extracapsular extension (P-value = 0.02) and a trend toward an increased Gleason score (P-value = 0.064). No significant association was observed between changes in mtDNA content and biochemical recurrence (median follow up of 107 months). CONCLUSIONS: Contrary to other cancer types, prostate cancer tissue shows no universally depleted mtDNA content. Rather, the change in mtDNA content is highly variable, mirroring known prostate cancer genome heterogeneity. Patients with high mtDNA content have an unfavorable pathology, while a high mtDNA content in normal adjacent prostate tissue is associated with worse prognosis.


Assuntos
Adenocarcinoma/genética , Variações do Número de Cópias de DNA , DNA Mitocondrial , Genoma Mitocondrial , Próstata/patologia , Neoplasias da Próstata/genética , Adenocarcinoma/patologia , Idoso , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/patologia
9.
J Med Ultrasound ; 26(1): 42-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30065512

RESUMO

OBJECTIVE: The objective of the study was to perform quantitative failure and fault analysis to the diagnostic ultrasound (US) scanners in a radiology department after the implementation of the predictive maintenance (PdM) method; to study the reduction trend of machine failure; to understand machine operating parameters affecting the failure; to further optimize the method to maximize the machine clinically service time. MATERIALS AND METHODS: The PdM method has been implemented to the 5 US machines since 2013. Log books were used to record machine failures and their root causes together with the time spent on repair, all of which were retrieved, categorized, and analyzed for the period between 2013 and 2016. RESULTS: There were a total of 108 cases of failure occurred in these 5 US machines during the 4-year study period. The average number of failure per month for all these machines was 2.4. Failure analysis showed that there were 33 cases (30.5%) due to software, 44 cases (40.7%) due to hardware, and 31 cases (28.7%) due to US probe. There was a statistically significant negative correlation between the time spent on regular quality assurance (QA) by hospital physicists with the time spent on faulty parts replacement over the study period (P = 0.007). However, there was no statistically significant correlation between regular QA time and total yearly breakdown case (P = 0.12), although there has been a decreasing trend observed in the yearly total breakdown. CONCLUSION: There has been a significant improvement on the machine failure of US machines attributed to the concerted effort of sonographers and physicists in our department to practice the PdM method, in that system component repair time has been reduced, and a decreasing trend in the number of system breakdown has been observed.

10.
Prostate ; 76(4): 349-58, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26660354

RESUMO

BACKGROUND: Prostate cancer incidence and mortality rates are significantly increased in African-American men, but limited studies have been performed within Sub-Saharan African populations. As mitochondria control energy metabolism and apoptosis we speculate that somatic mutations within mitochondrial genomes are candidate drivers of aggressive prostate carcinogenesis. METHODS: We used matched blood and prostate tissue samples from 87 South African men (77 with African ancestry) to perform deep sequencing of complete mitochondrial genomes. Clinical presentation was biased toward aggressive disease (Gleason score >7, 64%), and compared with men without prostate cancer either with or without benign prostatic hyperplasia. RESULTS: We identified 144 somatic mtDNA single nucleotide variants (SNVs), of which 80 were observed in 39 men presenting with aggressive disease. Both the number and frequency of somatic mtDNA SNVs were associated with higher pathological stage. CONCLUSIONS: Besides doubling the total number of somatic PCa-associated mitochondrial genome mutations identified to date, we associate mutational load with aggressive prostate cancer status in men of African ancestry.


Assuntos
DNA Mitocondrial/genética , Variação Genética/genética , Genoma Mitocondrial/genética , Neoplasias da Próstata/genética , Idoso , Idoso de 80 Anos ou mais , População Negra , DNA Mitocondrial/química , Predisposição Genética para Doença , Genótipo , Humanos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Mutação/genética , Gradação de Tumores , Polimorfismo de Nucleotídeo Único/genética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , África do Sul , População Branca
11.
PLoS Biol ; 9(8): e1001125, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21857804

RESUMO

BACKGROUND: Genome-wide association (GWA) is gaining popularity as a means to study the architecture of complex quantitative traits, partially due to the improvement of high-throughput low-cost genotyping and phenotyping technologies. Glucosinolate (GSL) secondary metabolites within Arabidopsis spp. can serve as a model system to understand the genomic architecture of adaptive quantitative traits. GSL are key anti-herbivory defenses that impart adaptive advantages within field trials. While little is known about how variation in the external or internal environment of an organism may influence the efficiency of GWA, GSL variation is known to be highly dependent upon the external stresses and developmental processes of the plant lending it to be an excellent model for studying conditional GWA. METHODOLOGY/PRINCIPAL FINDINGS: To understand how development and environment can influence GWA, we conducted a study using 96 Arabidopsis thaliana accessions, >40 GSL phenotypes across three conditions (one developmental comparison and one environmental comparison) and ∼230,000 SNPs. Developmental stage had dramatic effects on the outcome of GWA, with each stage identifying different loci associated with GSL traits. Further, while the molecular bases of numerous quantitative trait loci (QTL) controlling GSL traits have been identified, there is currently no estimate of how many additional genes may control natural variation in these traits. We developed a novel co-expression network approach to prioritize the thousands of GWA candidates and successfully validated a large number of these genes as influencing GSL accumulation within A. thaliana using single gene isogenic lines. CONCLUSIONS/SIGNIFICANCE: Together, these results suggest that complex traits imparting environmentally contingent adaptive advantages are likely influenced by up to thousands of loci that are sensitive to fluctuations in the environment or developmental state of the organism. Additionally, while GWA is highly conditional upon genetics, the use of additional genomic information can rapidly identify causal loci en masse.


Assuntos
Arabidopsis/genética , Estudo de Associação Genômica Ampla/métodos , Glucosinolatos/genética , Mapeamento Cromossômico , Locos de Características Quantitativas/genética
12.
Gigascience ; 132024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38837943

RESUMO

Genomic information is increasingly used to inform medical treatments and manage future disease risks. However, any personal and societal gains must be carefully balanced against the risk to individuals contributing their genomic data. Expanding our understanding of actionable genomic insights requires researchers to access large global datasets to capture the complexity of genomic contribution to diseases. Similarly, clinicians need efficient access to a patient's genome as well as population-representative historical records for evidence-based decisions. Both researchers and clinicians hence rely on participants to consent to the use of their genomic data, which in turn requires trust in the professional and ethical handling of this information. Here, we review existing and emerging solutions for secure and effective genomic information management, including storage, encryption, consent, and authorization that are needed to build participant trust. We discuss recent innovations in cloud computing, quantum-computing-proof encryption, and self-sovereign identity. These innovations can augment key developments from within the genomics community, notably GA4GH Passports and the Crypt4GH file container standard. We also explore how decentralized storage as well as the digital consenting process can offer culturally acceptable processes to encourage data contributions from ethnic minorities. We conclude that the individual and their right for self-determination needs to be put at the center of any genomics framework, because only on an individual level can the received benefits be accurately balanced against the risk of exposing private information.


Assuntos
Genômica , Humanos , Genômica/métodos , Genômica/ética , Segurança Computacional , Computação em Nuvem , Consentimento Livre e Esclarecido
13.
PLoS Genet ; 6(11): e1001198, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21079692

RESUMO

Discovering links between the genotype of an organism and its metabolite levels can increase our understanding of metabolism, its controls, and the indirect effects of metabolism on other quantitative traits. Recent technological advances in both DNA sequencing and metabolite profiling allow the use of broad-spectrum, untargeted metabolite profiling to generate phenotypic data for genome-wide association studies that investigate quantitative genetic control of metabolism within species. We conducted a genome-wide association study of natural variation in plant metabolism using the results of untargeted metabolite analyses performed on a collection of wild Arabidopsis thaliana accessions. Testing 327 metabolites against >200,000 single nucleotide polymorphisms identified numerous genotype-metabolite associations distributed non-randomly within the genome. These clusters of genotype-metabolite associations (hotspots) included regions of the A. thaliana genome previously identified as subject to recent strong positive selection (selective sweeps) and regions showing trans-linkage to these putative sweeps, suggesting that these selective forces have impacted genome-wide control of A. thaliana metabolism. Comparing the metabolic variation detected within this collection of wild accessions to a laboratory-derived population of recombinant inbred lines (derived from two of the accessions used in this study) showed that the higher level of genetic variation present within the wild accessions did not correspond to higher variance in metabolic phenotypes, suggesting that evolutionary constraints limit metabolic variation. While a major goal of genome-wide association studies is to develop catalogues of intraspecific variation, the results of multiple independent experiments performed for this study showed that the genotype-metabolite associations identified are sensitive to environmental fluctuations. Thus, studies of intraspecific variation conducted via genome-wide association will require analyses of genotype by environment interaction. Interestingly, the network structure of metabolite linkages was also sensitive to environmental differences, suggesting that key aspects of network architecture are malleable.


Assuntos
Arabidopsis/genética , Metaboloma/genética , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Padrões de Herança/genética , Desequilíbrio de Ligação/genética , Redes e Vias Metabólicas/genética
14.
bioRxiv ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36747621

RESUMO

Background: One difficulty in testing the hypothesis that the Australasian dingo is a functional intermediate between wild wolves and domesticated breed dogs is that there is no reference specimen. Here we link a high-quality de novo long read chromosomal assembly with epigenetic footprints and morphology to describe the Alpine dingo female named Cooinda. It was critical to establish an Alpine dingo reference because this ecotype occurs throughout coastal eastern Australia where the first drawings and descriptions were completed. Findings: We generated a high-quality chromosome-level reference genome assembly (Canfam_ADS) using a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. Compared to the previously published Desert dingo assembly, there are large structural rearrangements on Chromosomes 11, 16, 25 and 26. Phylogenetic analyses of chromosomal data from Cooinda the Alpine dingo and nine previously published de novo canine assemblies show dingoes are monophyletic and basal to domestic dogs. Network analyses show that the mtDNA genome clusters within the southeastern lineage, as expected for an Alpine dingo. Comparison of regulatory regions identified two differentially methylated regions within glucagon receptor GCGR and histone deacetylase HDAC4 genes that are unmethylated in the Alpine dingo genome but hypermethylated in the Desert dingo. Morphological data, comprising geometric morphometric assessment of cranial morphology place dingo Cooinda within population-level variation for Alpine dingoes. Magnetic resonance imaging of brain tissue show she had a larger cranial capacity than a similar-sized domestic dog. Conclusions: These combined data support the hypothesis that the dingo Cooinda fits the spectrum of genetic and morphological characteristics typical of the Alpine ecotype. We propose that she be considered the archetype specimen for future research investigating the evolutionary history, morphology, physiology, and ecology of dingoes. The female has been taxidermically prepared and is now at the Australian Museum, Sydney.

15.
Gigascience ; 122023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36994871

RESUMO

BACKGROUND: One difficulty in testing the hypothesis that the Australasian dingo is a functional intermediate between wild wolves and domesticated breed dogs is that there is no reference specimen. Here we link a high-quality de novo long-read chromosomal assembly with epigenetic footprints and morphology to describe the Alpine dingo female named Cooinda. It was critical to establish an Alpine dingo reference because this ecotype occurs throughout coastal eastern Australia where the first drawings and descriptions were completed. FINDINGS: We generated a high-quality chromosome-level reference genome assembly (Canfam_ADS) using a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. Compared to the previously published Desert dingo assembly, there are large structural rearrangements on chromosomes 11, 16, 25, and 26. Phylogenetic analyses of chromosomal data from Cooinda the Alpine dingo and 9 previously published de novo canine assemblies show dingoes are monophyletic and basal to domestic dogs. Network analyses show that the mitochondrial DNA genome clusters within the southeastern lineage, as expected for an Alpine dingo. Comparison of regulatory regions identified 2 differentially methylated regions within glucagon receptor GCGR and histone deacetylase HDAC4 genes that are unmethylated in the Alpine dingo genome but hypermethylated in the Desert dingo. Morphologic data, comprising geometric morphometric assessment of cranial morphology, place dingo Cooinda within population-level variation for Alpine dingoes. Magnetic resonance imaging of brain tissue shows she had a larger cranial capacity than a similar-sized domestic dog. CONCLUSIONS: These combined data support the hypothesis that the dingo Cooinda fits the spectrum of genetic and morphologic characteristics typical of the Alpine ecotype. We propose that she be considered the archetype specimen for future research investigating the evolutionary history, morphology, physiology, and ecology of dingoes. The female has been taxidermically prepared and is now at the Australian Museum, Sydney.


Assuntos
Canidae , Genoma Mitocondrial , Lobos , Cães , Animais , Feminino , Epigenoma , Filogenia , Austrália , Canidae/genética , Lobos/genética , Cromossomos
16.
PLoS Pathog ; 6(4): e1000861, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20419157

RESUMO

Despite the described central role of jasmonate signaling in plant defense against necrotrophic pathogens, the existence of intraspecific variation in pathogen capacity to activate or evade plant jasmonate-mediated defenses is rarely considered. Experimental infection of jasmonate-deficient and jasmonate-insensitive Arabidopsis thaliana with diverse isolates of the necrotrophic fungal pathogen Botrytis cinerea revealed pathogen variation for virulence inhibition by jasmonate-mediated plant defenses and induction of plant defense metabolites. Comparison of the transcriptional effects of infection by two distinct B. cinerea isolates showed only minor differences in transcriptional responses of wild-type plants, but notable isolate-specific transcript differences in jasmonate-insensitive plants. These transcriptional differences suggest B. cinerea activation of plant defenses that require plant jasmonate signaling for activity in response to only one of the two B. cinerea isolates tested. Thus, similar infection phenotypes observed in wild-type plants result from different signaling interactions with the plant that are likely integrated by jasmonate signaling.


Assuntos
Arabidopsis/imunologia , Ciclopentanos/imunologia , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Parasita/imunologia , Micoses/imunologia , Oxilipinas/imunologia , Arabidopsis/parasitologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Proteínas de Arabidopsis/metabolismo , Botrytis/genética , Botrytis/imunologia , Botrytis/patogenicidade , Ciclopentanos/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Indóis/imunologia , Indóis/metabolismo , Micoses/genética , Micoses/metabolismo , Oxilipinas/metabolismo , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/imunologia , Tiazóis/imunologia , Tiazóis/metabolismo
17.
Theor Appl Genet ; 125(8): 1603-18, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22875176

RESUMO

The first single-nucleotide polymorphism (SNP) maps for watermelon [Citrullus lanatus (Thunb.) Matsum. et Nakai] were constructed and compared. Three populations were developed from crosses between two elite cultivars, Klondike Black Seeded × New Hampshire Midget (KBS × NHM), an elite cultivar and wild egusi accession, Strain II × PI 560023 (SII × Egusi) and an elite cultivar and a wild citron accession, ZWRM50 × PI 244019 (ZWRM × Citroides). The SII × Egusi and ZWRM × Citroides F(2) populations consisted of 187 and 182 individuals respectively while the KBS × NHM recombinant inbred line (RIL) population consisted of 164 lines. The length of the genetic maps were 1,438, 1,514 and 1,144 cM with average marker distances of 3.8, 4.2, and 3.4 cM for the KBS × NHM, SII × Egusi and ZWRM × Citroides populations, respectively. Shared markers were used to align the three maps so that the linkage groups (LGs) represented the 11 chromosomes of the species. Marker segregation distortion were observed in all three populations, but was highest (12.7 %) in the ZWRM × Citroides population, where Citroides alleles were favored. The three maps were used to construct a consensus map containing 378 SNP markers with an average distance of 5.1 cM between markers. Phenotypic data was collected for fruit weight (FWT), fruit length (FL), fruit width (FWD), fruit shape index (FSI), rind thickness (RTH) and Brix (BRX) and analyzed for quantitative trait loci (QTL) associated with these traits. A total of 40 QTL were identified in the three populations, including major QTL for fruit size and shape that were stable across genetic backgrounds and environments. The present study reports the first SNP maps for Citrullus and the first map constructed using two elite parents. We also report the first stable QTL associated with fruit size and shape in Citrullus lanatus. These maps, QTL and SNPs should be useful for the watermelon community and represent a significant step towards the potential use of molecular tools in watermelon breeding.


Assuntos
Mapeamento Cromossômico/métodos , Citrullus/genética , Frutas/anatomia & histologia , Frutas/genética , Genética Populacional , Genoma de Planta/genética , Tamanho do Órgão/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável
18.
Genome Med ; 14(1): 100, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045381

RESUMO

BACKGROUND: African ancestry is a significant risk factor for advanced prostate cancer (PCa). Mortality rates in sub-Saharan Africa are 2.5-fold greater than global averages. However, the region has largely been excluded from the benefits of whole genome interrogation studies. Additionally, while structural variation (SV) is highly prevalent, PCa genomic studies are still biased towards small variant interrogation. METHODS: Using whole genome sequencing and best practice workflows, we performed a comprehensive analysis of SVs for 180 (predominantly Gleason score ≥ 8) prostate tumours derived from 115 African, 61 European and four ancestrally admixed patients. We investigated the landscape and relationship of somatic SVs in driving ethnic disparity (African versus European), with a focus on African men from southern Africa. RESULTS: Duplication events showed the greatest ethnic disparity, with a 1.6- (relative frequency) to 2.5-fold (count) increase in African-derived tumours. Furthermore, we found duplication events to be associated with CDK12 inactivation and MYC copy number gain, and deletion events associated with SPOP mutation. Overall, African-derived tumours were 2-fold more likely to present with a hyper-SV subtype. In addition to hyper-duplication and deletion subtypes, we describe a new hyper-translocation subtype. While we confirm a lower TMPRSS2-ERG fusion-positive rate in tumours from African cases (10% versus 33%), novel African-specific PCa ETS family member and TMPRSS2 fusion partners were identified, including LINC01525, FBXO7, GTF3C2, NTNG1 and YPEL5. Notably, we found 74 somatic SV hotspots impacting 18 new candidate driver genes, with CADM2, LSAMP, PTPRD, PDE4D and PACRG having therapeutic implications for African patients. CONCLUSIONS: In this first African-inclusive SV study for high-risk PCa, we demonstrate the power of SV interrogation for the identification of novel subtypes, oncogenic drivers and therapeutic targets. Identifying a novel spectrum of SVs in tumours derived from African patients provides a mechanism that may contribute, at least in part, to the observed ethnic disparity in advanced PCa presentation in men of African ancestry.


Assuntos
Neoplasias da Próstata , População Negra/genética , Carcinogênese/genética , Humanos , Masculino , Mutação , Gradação de Tumores , Proteínas Nucleares/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Repressoras/genética
19.
NPJ Regen Med ; 7(1): 31, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710627

RESUMO

The impact of aging on intestinal stem cells (ISCs) has not been fully elucidated. In this study, we identified widespread epigenetic and transcriptional alterations in old ISCs. Using a reprogramming algorithm, we identified a set of key transcription factors (Egr1, Irf1, FosB) that drives molecular and functional differences between old and young states. Overall, by dissecting the molecular signature of aged ISCs, our study identified transcription factors that enhance the regenerative capacity of ISCs.

20.
Sci Adv ; 8(16): eabm5944, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35452284

RESUMO

Dogs are uniquely associated with human dispersal and bring transformational insight into the domestication process. Dingoes represent an intriguing case within canine evolution being geographically isolated for thousands of years. Here, we present a high-quality de novo assembly of a pure dingo (CanFam_DDS). We identified large chromosomal differences relative to the current dog reference (CanFam3.1) and confirmed no expanded pancreatic amylase gene as found in breed dogs. Phylogenetic analyses using variant pairwise matrices show that the dingo is distinct from five breed dogs with 100% bootstrap support when using Greenland wolf as the outgroup. Functionally, we observe differences in methylation patterns between the dingo and German shepherd dog genomes and differences in serum biochemistry and microbiome makeup. Our results suggest that distinct demographic and environmental conditions have shaped the dingo genome. In contrast, artificial human selection has likely shaped the genomes of domestic breed dogs after divergence from the dingo.


Assuntos
Canidae , Lobos , Animais , Austrália , Cruzamento , Canidae/genética , Cães , Filogenia , Lobos/genética
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