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1.
Cell ; 173(3): 595-610.e11, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29656894

RESUMO

The evolutionary features of clear-cell renal cell carcinoma (ccRCC) have not been systematically studied to date. We analyzed 1,206 primary tumor regions from 101 patients recruited into the multi-center prospective study, TRACERx Renal. We observe up to 30 driver events per tumor and show that subclonal diversification is associated with known prognostic parameters. By resolving the patterns of driver event ordering, co-occurrence, and mutual exclusivity at clone level, we show the deterministic nature of clonal evolution. ccRCC can be grouped into seven evolutionary subtypes, ranging from tumors characterized by early fixation of multiple mutational and copy number drivers and rapid metastases to highly branched tumors with >10 subclonal drivers and extensive parallel evolution associated with attenuated progression. We identify genetic diversity and chromosomal complexity as determinants of patient outcome. Our insights reconcile the variable clinical behavior of ccRCC and suggest evolutionary potential as a biomarker for both intervention and surveillance.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Biomarcadores Tumorais , Cromossomos , Evolução Clonal , Progressão da Doença , Evolução Molecular , Feminino , Heterogeneidade Genética , Variação Genética , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Mutação , Metástase Neoplásica , Fenótipo , Filogenia , Prognóstico , Estudos Prospectivos , Análise de Sequência de DNA
2.
Nat Immunol ; 20(3): 374, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30733606

RESUMO

In the version of this article initially published, the Supplementary Data file was an incorrect version. The correct version is now provided. The error has been corrected in the HTML and PDF version of the article.

3.
Nat Immunol ; 19(5): 497-507, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29662170

RESUMO

The transcription factor c-Maf induces the anti-inflammatory cytokine IL-10 in CD4+ T cells in vitro. However, the global effects of c-Maf on diverse immune responses in vivo are unknown. Here we found that c-Maf regulated IL-10 production in CD4+ T cells in disease models involving the TH1 subset of helper T cells (malaria), TH2 cells (allergy) and TH17 cells (autoimmunity) in vivo. Although mice with c-Maf deficiency targeted to T cells showed greater pathology in TH1 and TH2 responses, TH17 cell-mediated pathology was reduced in this context, with an accompanying decrease in TH17 cells and increase in Foxp3+ regulatory T cells. Bivariate genomic footprinting elucidated the c-Maf transcription-factor network, including enhanced activity of NFAT; this led to the identification and validation of c-Maf as a negative regulator of IL-2. The decreased expression of the gene encoding the transcription factor RORγt (Rorc) that resulted from c-Maf deficiency was dependent on IL-2, which explained the in vivo observations. Thus, c-Maf is a positive and negative regulator of the expression of cytokine-encoding genes, with context-specific effects that allow each immune response to occur in a controlled yet effective manner.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Redes Reguladoras de Genes/imunologia , Interleucina-2/biossíntese , Proteínas Proto-Oncogênicas c-maf/imunologia , Animais , Interleucina-2/imunologia , Camundongos
4.
Nature ; 611(7934): 105-114, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36198798

RESUMO

DNA transfer from cytoplasmic organelles to the cell nucleus is a legacy of the endosymbiotic event-the majority of nuclear-mitochondrial segments (NUMTs) are thought to be ancient, preceding human speciation1-3. Here we analyse whole-genome sequences from 66,083 people-including 12,509 people with cancer-and demonstrate the ongoing transfer of mitochondrial DNA into the nucleus, contributing to a complex NUMT landscape. More than 99% of individuals had at least one of 1,637 different NUMTs, with 1 in 8 individuals having an ultra-rare NUMT that is present in less than 0.1% of the population. More than 90% of the extant NUMTs that we evaluated inserted into the nuclear genome after humans diverged from apes. Once embedded, the sequences were no longer under the evolutionary constraint seen within the mitochondrion, and NUMT-specific mutations had a different mutational signature to mitochondrial DNA. De novo NUMTs were observed in the germline once in every 104 births and once in every 103 cancers. NUMTs preferentially involved non-coding mitochondrial DNA, linking transcription and replication to their origin, with nuclear insertion involving multiple mechanisms including double-strand break repair associated with PR domain zinc-finger protein 9 (PRDM9) binding. The frequency of tumour-specific NUMTs differed between cancers, including a probably causal insertion in a myxoid liposarcoma. We found evidence of selection against NUMTs on the basis of size and genomic location, shaping a highly heterogenous and dynamic human NUMT landscape.


Assuntos
Núcleo Celular , DNA Mitocondrial , Genoma Humano , Humanos , Núcleo Celular/genética , Núcleo Celular/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Genoma Humano/genética , Mitocôndrias/genética , Filogenia , Análise de Sequência de DNA , Mutação , Lipossarcoma Mixoide/genética , Neoplasias/genética , Mutação em Linhagem Germinativa , Quebras de DNA de Cadeia Dupla , Reparo do DNA
5.
Nature ; 607(7917): 97-103, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255492

RESUMO

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2-4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes-including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)-in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease.


Assuntos
COVID-19 , Estado Terminal , Genoma Humano , Interações Hospedeiro-Patógeno , Sequenciamento Completo do Genoma , Transportadores de Cassetes de Ligação de ATP , COVID-19/genética , COVID-19/mortalidade , COVID-19/patologia , COVID-19/virologia , Moléculas de Adesão Celular , Cuidados Críticos , Estado Terminal/mortalidade , Selectina E , Fator VIII , Fucosiltransferases , Genoma Humano/genética , Estudo de Associação Genômica Ampla , Interações Hospedeiro-Patógeno/genética , Humanos , Subunidade beta de Receptor de Interleucina-10 , Lectinas Tipo C , Mucina-1 , Proteínas do Tecido Nervoso , Proteínas de Transferência de Fosfolipídeos , Receptores de Superfície Celular , Proteínas Repressoras , SARS-CoV-2/patogenicidade , Galactosídeo 2-alfa-L-Fucosiltransferase
6.
J Transl Med ; 21(1): 825, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978513

RESUMO

BACKGROUND: Causative genetic variants cannot yet be found for many disorders with a clear heritable component, including chronic fatigue disorders like myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). These conditions may involve genes in difficult-to-align genomic regions that are refractory to short read approaches. Structural variants in these regions can be particularly hard to detect or define with short reads, yet may account for a significant number of cases. Long read sequencing can overcome these difficulties but so far little data is available regarding the specific analytical challenges inherent in such regions, which need to be taken into account to ensure that variants are correctly identified. Research into chronic fatigue disorders faces the additional challenge that the heterogeneous patient populations likely encompass multiple aetiologies with overlapping symptoms, rather than a single disease entity, such that each individual abnormality may lack statistical significance within a larger sample. Better delineation of patient subgroups is needed to target research and treatment. METHODS: We use nanopore sequencing in a case of unexplained severe fatigue to identify and fully characterise a large inversion in a highly homologous region spanning the AKR1C gene locus, which was indicated but could not be resolved by short-read sequencing. We then use GC-MS/MS serum steroid analysis to investigate the functional consequences. RESULTS: Several commonly used bioinformatics tools are confounded by the homology but a combined approach including visual inspection allows the variant to be accurately resolved. The DNA inversion appears to increase the expression of AKR1C2 while limiting AKR1C1 activity, resulting in a relative increase of inhibitory GABAergic neurosteroids and impaired progesterone metabolism which could suppress neuronal activity and interfere with cellular function in a wide range of tissues. CONCLUSIONS: This study provides an example of how long read sequencing can improve diagnostic yield in research and clinical care, and highlights some of the analytical challenges presented by regions containing tandem arrays of genes. It also proposes a novel gene associated with a novel disease aetiology that may be an underlying cause of complex chronic fatigue. It reveals biomarkers that could now be assessed in a larger cohort, potentially identifying a subset of patients who might respond to treatments suggested by the aetiology.


Assuntos
Síndrome de Fadiga Crônica , Humanos , Espectrometria de Massas em Tandem , Biomarcadores , Hidroxiesteroide Desidrogenases
7.
Brain ; 144(2): 584-600, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33559681

RESUMO

The extracellular matrix comprises a network of macromolecules such as collagens, proteoglycans and glycoproteins. VWA1 (von Willebrand factor A domain containing 1) encodes a component of the extracellular matrix that interacts with perlecan/collagen VI, appears to be involved in stabilizing extracellular matrix structures, and demonstrates high expression levels in tibial nerve. Vwa1-deficient mice manifest with abnormal peripheral nerve structure/function; however, VWA1 variants have not previously been associated with human disease. By interrogating the genome sequences of 74 180 individuals from the 100K Genomes Project in combination with international gene-matching efforts and targeted sequencing, we identified 17 individuals from 15 families with an autosomal-recessive, non-length dependent, hereditary motor neuropathy and rare biallelic variants in VWA1. A single disease-associated allele p.(G25Rfs*74), a 10-bp repeat expansion, was observed in 14/15 families and was homozygous in 10/15. Given an allele frequency in European populations approaching 1/1000, the seven unrelated homozygote individuals ascertained from the 100K Genomes Project represents a substantial enrichment above expected. Haplotype analysis identified a shared 220 kb region suggesting that this founder mutation arose >7000 years ago. A wide age-range of patients (6-83 years) helped delineate the clinical phenotype over time. The commonest disease presentation in the cohort was an early-onset (mean 2.0 ± 1.4 years) non-length-dependent axonal hereditary motor neuropathy, confirmed on electrophysiology, which will have to be differentiated from other predominantly or pure motor neuropathies and neuronopathies. Because of slow disease progression, ambulation was largely preserved. Neurophysiology, muscle histopathology, and muscle MRI findings typically revealed clear neurogenic changes with single isolated cases displaying additional myopathic process. We speculate that a few findings of myopathic changes might be secondary to chronic denervation rather than indicating an additional myopathic disease process. Duplex reverse transcription polymerase chain reaction and immunoblotting using patient fibroblasts revealed that the founder allele results in partial nonsense mediated decay and an absence of detectable protein. CRISPR and morpholino vwa1 modelling in zebrafish demonstrated reductions in motor neuron axonal growth, synaptic formation in the skeletal muscles and locomotive behaviour. In summary, we estimate that biallelic variants in VWA1 may be responsible for up to 1% of unexplained hereditary motor neuropathy cases in Europeans. The detailed clinical characterization provided here will facilitate targeted testing on suitable patient cohorts. This novel disease gene may have previously evaded detection because of high GC content, consequential low coverage and computational difficulties associated with robustly detecting repeat-expansions. Reviewing previously unsolved exomes using lower QC filters may generate further diagnoses.


Assuntos
Proteínas da Matriz Extracelular/genética , Neuropatia Hereditária Motora e Sensorial/genética , Adulto , Idoso , Animais , Comportamento Animal/fisiologia , Criança , Feminino , Neuropatia Hereditária Motora e Sensorial/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Mutação , Linhagem , Adulto Jovem , Peixe-Zebra
8.
Genet Med ; 23(9): 1636-1647, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34145395

RESUMO

PURPOSE: Much of the heredity of melanoma remains unexplained. We sought predisposing germline copy-number variants using a rare disease approach. METHODS: Whole-genome copy-number findings in patients with melanoma predisposition syndrome congenital melanocytic nevus were extrapolated to a sporadic melanoma cohort. Functional effects of duplications in PPP2R3B were investigated using immunohistochemistry, transcriptomics, and stable inducible cellular models, themselves characterized using RNAseq, quantitative real-time polymerase chain reaction (qRT-PCR), reverse phase protein arrays, immunoblotting, RNA interference, immunocytochemistry, proliferation, and migration assays. RESULTS: We identify here a previously unreported genetic susceptibility to melanoma and melanocytic nevi, familial duplications of gene PPP2R3B. This encodes PR70, a regulatory unit of critical phosphatase PP2A. Duplications increase expression of PR70 in human nevus, and increased expression in melanoma tissue correlates with survival via a nonimmunological mechanism. PPP2R3B overexpression induces pigment cell switching toward proliferation and away from migration. Importantly, this is independent of the known microphthalmia-associated transcription factor (MITF)-controlled switch, instead driven by C21orf91. Finally, C21orf91 is demonstrated to be downstream of MITF as well as PR70. CONCLUSION: This work confirms the power of a rare disease approach, identifying a previously unreported copy-number change predisposing to melanocytic neoplasia, and discovers C21orf91 as a potentially targetable hub in the control of phenotype switching.


Assuntos
Melanoma , Nevo , Neoplasias Cutâneas , Humanos , Imuno-Histoquímica , Melanoma/genética , Fenótipo , Neoplasias Cutâneas/genética
9.
Nucleic Acids Res ; 45(22): 12808-12815, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29106596

RESUMO

All DNA polymerases misincorporate ribonucleotides despite their preference for deoxyribonucleotides, and analysis of cultured cells indicates that mammalian mitochondrial DNA (mtDNA) tolerates such replication errors. However, it is not clear to what extent misincorporation occurs in tissues, or whether this plays a role in human disease. Here, we show that mtDNA of solid tissues contains many more embedded ribonucleotides than that of cultured cells, consistent with the high ratio of ribonucleotide to deoxynucleotide triphosphates in tissues, and that riboadenosines account for three-quarters of them. The pattern of embedded ribonucleotides changes in a mouse model of Mpv17 deficiency, which displays a marked increase in rGMPs in mtDNA. However, while the mitochondrial dGTP is low in the Mpv17-/- liver, the brain shows no change in the overall dGTP pool, leading us to suggest that Mpv17 determines the local concentration or quality of dGTP. Embedded rGMPs are expected to distort the mtDNA and impede its replication, and elevated rGMP incorporation is associated with early-onset mtDNA depletion in liver and late-onset multiple deletions in brain of Mpv17-/- mice. These findings suggest aberrant ribonucleotide incorporation is a primary mtDNA abnormality that can result in pathology.


Assuntos
DNA Mitocondrial/genética , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Ribonucleotídeos/genética , Deleção de Sequência , Animais , Sequência de Bases , Encéfalo/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Fígado/metabolismo , Proteínas de Membrana/deficiência , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Proteínas Mitocondriais/deficiência
10.
PLoS Genet ; 12(1): e1005779, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26760297

RESUMO

MPV17 is a mitochondrial inner membrane protein whose dysfunction causes mitochondrial DNA abnormalities and disease by an unknown mechanism. Perturbations of deoxynucleoside triphosphate (dNTP) pools are a recognized cause of mitochondrial genomic instability; therefore, we determined DNA copy number and dNTP levels in mitochondria of two models of MPV17 deficiency. In Mpv17 ablated mice, liver mitochondria showed substantial decreases in the levels of dGTP and dTTP and severe mitochondrial DNA depletion, whereas the dNTP pool was not significantly altered in kidney and brain mitochondria that had near normal levels of DNA. The shortage of mitochondrial dNTPs in Mpv17-/- liver slows the DNA replication in the organelle, as evidenced by the elevated level of replication intermediates. Quiescent fibroblasts of MPV17-mutant patients recapitulate key features of the primary affected tissue of the Mpv17-/- mice, displaying virtual absence of the protein, decreased dNTP levels and mitochondrial DNA depletion. Notably, the mitochondrial DNA loss in the patients' quiescent fibroblasts was prevented and rescued by deoxynucleoside supplementation. Thus, our study establishes dNTP insufficiency in the mitochondria as the cause of mitochondrial DNA depletion in MPV17 deficiency, and identifies deoxynucleoside supplementation as a potential therapeutic strategy for MPV17-related disease. Moreover, changes in the expression of factors involved in mitochondrial deoxynucleotide homeostasis indicate a remodeling of nucleotide metabolism in MPV17 disease models, which suggests mitochondria lacking functional MPV17 have a restricted purine mitochondrial salvage pathway.


Assuntos
Replicação do DNA/genética , DNA Mitocondrial/genética , Proteínas de Membrana/genética , Mitocôndrias Hepáticas/genética , Animais , Nucleotídeos de Desoxiguanina/genética , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas de Membrana/deficiência , Camundongos , Mitocôndrias Hepáticas/metabolismo , Transdução de Sinais , Nucleotídeos de Timina/genética
11.
Nature ; 487(7406): 254-8, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22722828

RESUMO

In female (XX) mammals, one of the two X chromosomes is inactivated to ensure an equal dose of X-linked genes with males (XY). X-chromosome inactivation in eutherian mammals is mediated by the non-coding RNA Xist. Xist is not found in metatherians (marsupials), and how X-chromosome inactivation is initiated in these mammals has been the subject of speculation for decades. Using the marsupial Monodelphis domestica, here we identify Rsx (RNA-on-the-silent X), an RNA that has properties consistent with a role in X-chromosome inactivation. Rsx is a large, repeat-rich RNA that is expressed only in females and is transcribed from, and coats, the inactive X chromosome. In female germ cells, in which both X chromosomes are active, Rsx is silenced, linking Rsx expression to X-chromosome inactivation and reactivation. Integration of an Rsx transgene on an autosome in mouse embryonic stem cells leads to gene silencing in cis. Our findings permit comparative studies of X-chromosome inactivation in mammals and pose questions about the mechanisms by which X-chromosome inactivation is achieved in eutherians.


Assuntos
Monodelphis/genética , Monodelphis/metabolismo , RNA/genética , RNA/metabolismo , Inativação do Cromossomo X , Cromossomo X/genética , Cromossomo X/metabolismo , Animais , Feminino , Regulação da Expressão Gênica , Inativação Gênica , Camundongos , Transgenes
12.
PLoS Genet ; 9(11): e1003904, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24282393

RESUMO

Urochordates are the closest relatives of vertebrates and at the larval stage, possess a characteristic bilateral chordate body plan. In vertebrates, the genes that orchestrate embryonic patterning are in part regulated by highly conserved non-coding elements (CNEs), yet these elements have not been identified in urochordate genomes. Consequently the evolution of the cis-regulatory code for urochordate development remains largely uncharacterised. Here, we use genome-wide comparisons between C. intestinalis and C. savignyi to identify putative urochordate cis-regulatory sequences. Ciona conserved non-coding elements (ciCNEs) are associated with largely the same key regulatory genes as vertebrate CNEs. Furthermore, some of the tested ciCNEs are able to activate reporter gene expression in both zebrafish and Ciona embryos, in a pattern that at least partially overlaps that of the gene they associate with, despite the absence of sequence identity. We also show that the ability of a ciCNE to up-regulate gene expression in vertebrate embryos can in some cases be localised to short sub-sequences, suggesting that functional cross-talk may be defined by small regions of ancestral regulatory logic, although functional sub-sequences may also be dispersed across the whole element. We conclude that the structure and organisation of cis-regulatory modules is very different between vertebrates and urochordates, reflecting their separate evolutionary histories. However, functional cross-talk still exists because the same repertoire of transcription factors has likely guided their parallel evolution, exploiting similar sets of binding sites but in different combinations.


Assuntos
Ciona intestinalis/genética , Evolução Molecular , Redes Reguladoras de Genes , Peixe-Zebra/genética , Animais , Sequência Conservada , Regulação da Expressão Gênica , Urocordados , Vertebrados/genética
13.
Dev Dyn ; 244(5): 681-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25715918

RESUMO

BACKGROUND: GLI2, a zinc finger transcription factor, mediates Sonic hedgehog signaling, a critical pathway in vertebrate embryogenesis. GLI2 has been implicated in diverse set of embryonic developmental processes, including patterning of central nervous system and limbs. In humans, mutations in GLI2 are associated with several developmental defects, including holoprosencephaly and polydactyly. RESULTS: Here, we demonstrate in transient transgenic zebrafish assays, the potential of a subset of tetrapod-teleost conserved non-coding elements (CNEs) residing within human GLI2 intronic intervals to induce reporter gene expression at known regions of endogenous GLI2 transcription. The regulatory activities of these elements are observed in several embryonic domains, including neural tube and pectoral fin. Moreover, our data reveal an overlapping expression profile of duplicated copies of an enhancer during zebrafish evolution. CONCLUSIONS: Our data suggest that during vertebrate history GLI2 acquired a high level of complexity in the genetic mechanisms regulating its expression during spatiotemporal patterning of the central nervous system (CNS) and limbs.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição Kruppel-Like/biossíntese , Botões de Extremidades/embriologia , Tubo Neural/embriologia , Proteínas Nucleares/biossíntese , Fatores de Transcrição/biossíntese , Proteínas de Peixe-Zebra/biossíntese , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Humanos , Fatores de Transcrição Kruppel-Like/genética , Botões de Extremidades/citologia , Tubo Neural/citologia , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Transcrição Gênica , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteína Gli2 com Dedos de Zinco
14.
Dev Biol ; 390(2): 261-72, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24680932

RESUMO

Vertebrate genomes share numerous conserved non-coding elements, many of which function as enhancer elements and are hypothesised to be under evolutionary constraint due to a need to be bound by combinations of sequence-specific transcription factors. In contrast, few such conserved elements can be detected between vertebrates and their closest invertebrate relatives. Despite this lack of sequence identity, cross-species transgenesis has identified some cases where non-coding DNA from invertebrates drives reporter gene expression in transgenic vertebrates in patterns reminiscent of the expression of vertebrate orthologues. Such instances are presumed to reflect the presence of conserved suites of binding sites in the regulatory regions of invertebrate and vertebrate orthologues, such that both regulatory elements can correctly interpret the trans-activating environment. Shuffling of binding sites has been suggested to lie behind loss of sequence conservation; however this has not been experimentally tested. Here we examine the underlying basis of enhancer activity for the Ciona intestinalis ßγ-crystallin gene, which drives expression in the lens of transgenic vertebrates despite the Ciona lineage predating the evolution of the lens. We construct an interactive gene regulatory network (GRN) for vertebrate lens development, allowing network interactions to be robustly catalogued and conserved network components and features to be identified. We show that a small number of binding motifs are necessary for Ciona ßγ-crystallin expression, and narrow down the likely factors that bind to these motifs. Several of these overlap with the conserved core of the vertebrate lens GRN, implicating these sites in cross species function. However when we test these motifs in a transgenic vertebrate they prove to be dispensable for reporter expression in the lens. These results show that current models depicting cross species enhancer function as dependent on conserved binding sites can be overly simplistic, with sound evolutionary inference requiring detailed dissection of underlying mechanisms.


Assuntos
Evolução Biológica , Ciona intestinalis/genética , Elementos Facilitadores Genéticos/genética , Redes Reguladoras de Genes/genética , Cristalino/embriologia , Fatores de Transcrição/metabolismo , Animais , Galinhas , Cristalinas/genética , Análise Mutacional de DNA , Eletroporação , Técnicas de Transferência de Genes , Cristalino/metabolismo , Camundongos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , Especificidade da Espécie , Fatores de Transcrição/genética , Xenopus laevis , Peixe-Zebra
15.
Dev Growth Differ ; 57(8): 570-80, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26464005

RESUMO

The zinc-finger transcription factor GLI3 acts as a primary transducer of Sonic hedgehog (Shh) signaling in a context-dependent combinatorial fashion. GLI3 participates in the patterning and growth of many organs, including the central nervous system (CNS) and limbs. Previously, we reported a subset of human intronic cis-regulators controlling many known aspects of endogenous Gli3 expression in mouse and zebrafish. Here we demonstrate in a transgenic zebrafish assay the potential of two novel tetrapod-teleost conserved non-coding elements (CNEs) docking within GLI3 intronic intervals (intron 3 and 4) to induce reporter gene expression at known sites of endogenous Gli3 transcription in embryonic domains such as the central nervous system (CNS) and limbs. Interestingly, the cell culture based assays reveal harmony with the context dependent dual nature of intra-GLI3 conserved elements. Furthermore, a transgenic zebrafish assay of previously reported limb-specific GLI3 transcriptional enhancers (previously tested in mice and chicken limb buds) induced reporter gene expression in zebrafish blood precursor cells and notochord instead of fin. These results demonstrate that the appendage-specific activity of a subset of GLI3-associated enhancers might be a tetrapod innovation. Taken together with our recent data, these results suggest that during the course of vertebrate evolution Gli3 expression control acquired a complex cis-regulatory landscape for spatiotemporal patterning of CNS and limbs. Comparative data from fish and mice suggest that the functional aspects of a subset of these cis-regulators have diverged significantly between these two lineages.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fatores de Transcrição/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Elementos Facilitadores Genéticos/genética , Elementos Facilitadores Genéticos/fisiologia , Humanos , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição/genética , Peixe-Zebra/genética , Proteína Gli3 com Dedos de Zinco
16.
Development ; 138(5): 879-84, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21247963

RESUMO

Within the vertebrate lineage, a high proportion of duplicate genes have been retained after whole genome duplication (WGD) events. It has been proposed that many of these duplicate genes became indispensable because the ancestral gene function was divided between them. In addition, novel functions may have evolved, owing to changes in cis-regulatory elements. Functional analysis of the PAX2/5/8 gene subfamily appears to support at least the first part of this hypothesis. The collective role of these genes has been widely retained, but sub-functions have been differentially partitioned between the genes in different vertebrates. Conserved non-coding elements (CNEs) represent an interesting and readily identifiable class of putative cis-regulatory elements that have been conserved from fish to mammals, an evolutionary distance of 450 million years. Within the PAX2/5/8 gene subfamily, PAX2 is associated with the highest number of CNEs. An additional WGD experienced in the teleost lineage led to two copies of pax2, each of which retained a large proportion of these CNEs. Using a reporter gene assay in zebrafish embryos, we have exploited this rich collection of regulatory elements in order to determine whether duplicate CNEs have evolved different functions. Remarkably, we find that even highly conserved sequences exhibit more functional differences than similarities. We also discover that short flanking sequences can have a profound impact on CNE function. Therefore, if CNEs are to be used as candidate enhancers for transgenic studies or for multi-species comparative analyses, it is paramount that the CNEs are accurately delineated.


Assuntos
Sequência Conservada , Elementos Facilitadores Genéticos/fisiologia , Genes Duplicados , Genoma/genética , Animais , Biologia Computacional , Embrião não Mamífero , Genes Reporter , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/fisiologia , Fator de Transcrição PAX5 , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados , Pesquisa/normas , Peixe-Zebra , Proteínas de Peixe-Zebra
17.
Genes (Basel) ; 15(7)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39062704

RESUMO

The identification of structural variants (SVs) in genomic data represents an ongoing challenge because of difficulties in reliable SV calling leading to reduced sensitivity and specificity. We prepared high-quality DNA from 9 parent-child trios, who had previously undergone short-read whole-genome sequencing (Illumina platform) as part of the Genomics England 100,000 Genomes Project. We reanalysed the genomes using both Bionano optical genome mapping (OGM; 8 probands and one trio) and Nanopore long-read sequencing (Oxford Nanopore Technologies [ONT] platform; all samples). To establish a "truth" dataset, we asked whether rare proband SV calls (n = 234) made by the Bionano Access (version 1.6.1)/Solve software (version 3.6.1_11162020) could be verified by individual visualisation using the Integrative Genomics Viewer with either or both of the Illumina and ONT raw sequence. Of these, 222 calls were verified, indicating that Bionano OGM calls have high precision (positive predictive value 95%). We then asked what proportion of the 222 true Bionano SVs had been identified by SV callers in the other two datasets. In the Illumina dataset, sensitivity varied according to variant type, being high for deletions (115/134; 86%) but poor for insertions (13/58; 22%). In the ONT dataset, sensitivity was generally poor using the original Sniffles variant caller (48% overall) but improved substantially with use of Sniffles2 (36/40; 90% and 17/23; 74% for deletions and insertions, respectively). In summary, we show that the precision of OGM is very high. In addition, when applying the Sniffles2 caller, the sensitivity of SV calling using ONT long-read sequence data outperforms Illumina sequencing for most SV types.


Assuntos
Benchmarking , Sequenciamento por Nanoporos , Sequenciamento Completo do Genoma , Humanos , Sequenciamento Completo do Genoma/métodos , Sequenciamento Completo do Genoma/normas , Sequenciamento por Nanoporos/métodos , Benchmarking/métodos , Variação Estrutural do Genoma/genética , Mapeamento Cromossômico/métodos , Genoma Humano/genética , Genômica/métodos , Software , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/normas , Feminino , Nanoporos , Masculino , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/normas
18.
Nat Commun ; 15(1): 7731, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39231944

RESUMO

Whole genome sequencing (WGS) provides comprehensive, individualised cancer genomic information. However, routine tumour biopsies are formalin-fixed and paraffin-embedded (FFPE), damaging DNA, historically limiting their use in WGS. Here we analyse FFPE cancer WGS datasets from England's 100,000 Genomes Project, comparing 578 FFPE samples with 11,014 fresh frozen (FF) samples across multiple tumour types. We use an approach that characterises rather than discards artefacts. We identify three artefactual signatures, including one known (SBS57) and two previously uncharacterised (SBS FFPE, ID FFPE), and develop an "FFPEImpact" score that quantifies sample artefacts. Despite inferior sequencing quality, FFPE-derived data identifies clinically-actionable variants, mutational signatures and permits algorithmic stratification. Matched FF/FFPE validation cohorts shows good concordance while acknowledging SBS, ID and copy-number artefacts. While FF-derived WGS data remains the gold standard, FFPE-samples can be used for WGS if required, using analytical advancements developed here, potentially democratising whole cancer genomics to many.


Assuntos
Formaldeído , Neoplasias , Inclusão em Parafina , Fixação de Tecidos , Sequenciamento Completo do Genoma , Humanos , Inclusão em Parafina/métodos , Neoplasias/genética , Neoplasias/patologia , Sequenciamento Completo do Genoma/métodos , Fixação de Tecidos/métodos , Genômica/métodos , Mutação , Genoma Humano , Artefatos
19.
J Clin Oncol ; : JCO2302761, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39481076

RESUMO

PURPOSE: As part of the 100,000 Genomes Project, we set out to assess the potential viability and clinical impact of reporting genetic variants associated with drug-induced toxicity for patients with cancer recruited for whole-genome sequencing (WGS) as part of a genomic medicine service. METHODS: Germline WGS from 76,805 participants was analyzed for pharmacogenetic (PGx) variants in four genes (DPYD, NUDT15, TPMT, UGT1A1) associated with toxicity induced by five drugs used in cancer treatment (capecitabine, fluorouracil, mercaptopurine, thioguanine, irinotecan). Linking genomic data with prescribing and hospital incidence records, a phenome-wide association study (PheWAS) was performed to identify whether phenotypes indicative of adverse drug reactions (ADRs) were enriched in drug-exposed individuals with the relevant PGx variants. In a subset of 7,081 patients with cancer, DPYD variants were reported back to clinicians and outcomes were collected. RESULTS: We identified clinically relevant PGx variants across the four genes in 62.7% of participants in our cohort. Extending this to annual prescription numbers in England for the drugs affected by these PGx variants, approximately 14,540 patients per year could potentially benefit from a reduced dose or alternative drug to reduce the risk of ADRs. Validating PGx associations in a real-world data set, we found a significant association between PGx variants in DPYD and toxicity-related phenotypes in patients treated with capecitabine or fluorouracil. Reported DPYD variants were deemed informative for clinical decision making in a majority of cases. CONCLUSION: Reporting PGx variants from germline WGS relevant to patients with cancer alongside primary findings related to their cancer can be clinically informative, informing prescribing to reduce the risk of ADRs. Extending the range of actionable variants to those found in patients of non-European ancestry is important and will extend the potential clinical impact.

20.
Dev Biol ; 365(1): 310-8, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22387845

RESUMO

Highly conserved non-coding elements (CNEs) linked to genes involved in embryonic development have been hypothesised to correspond to cis-regulatory modules due to their ability to induce tissue-specific expression patterns. However, attempts to prove their requirement for normal development or for the correct expression of the genes they are associated with have yielded conflicting results. Here, we show that CNEs at the vertebrate Sox21 locus are crucial for Sox21 expression in the embryonic lens and that loss of Sox21 function interferes with normal lens development. Using different expression assays in zebrafish we find that two CNEs linked to Sox21 in all vertebrates contain lens enhancers and that their removal from a reporter BAC abolishes lens expression. Furthermore inhibition of Sox21 function after the injection of a sox21b morpholino into zebrafish leads to defects in lens development. These findings identify a direct link between sequence conservation and genomic function of regulatory sequences. In addition to this we provide evidence that putative Sox binding sites in one of the CNEs are essential for induction of lens expression as well as enhancer function in the CNS. Our results show that CNEs identified in pufferfish-mammal whole-genome comparisons are crucial developmental enhancers and hence essential components of gene regulatory networks underlying vertebrate embryogenesis.


Assuntos
Cristalino/embriologia , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição SOXB2/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Animais , Sequência Conservada , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Cristalino/fisiologia
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