Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
2.
Chemistry ; 27(72): 18118-18128, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34747070

RESUMO

Recognition-driven modification has been emerging as a novel approach to modifying biomolecular targets of interest site-specifically and efficiently. To this end, protein modular adaptors (MAs) are the ideal reaction model for recognition-driven modification of DNA as they consist of both a sequence-specific DNA-binding domain (DBD) and a self-ligating protein-tag. Coupling DNA recognition by DBD and the chemoselective reaction of the protein tag could provide a highly efficient sequence-specific reaction. However, combining an MA consisting of a reactive protein-tag and its substrate, for example, SNAP-tag and benzyl guanine (BG), revealed rather nonselective reaction with DNA. Therefore new substrates of SNAP-tag have been designed to realize sequence-selective rapid crosslinking reactions of MAs with SNAP-tag. The reactions of substrates with SNAP-tag were verified by kinetic analyses to enable the sequence-selective crosslinking reaction of MA. The new substrate enables the distinctive orthogonality of SNAP-tag against CLIP-tag to achieve orthogonal DNA-protein crosslinking by six unique MAs.


Assuntos
Corantes Fluorescentes , O(6)-Metilguanina-DNA Metiltransferase , DNA , Guanina , Proteínas
3.
Nature ; 527(7579): 459-65, 2015 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-26580012

RESUMO

Acorn worms, also known as enteropneust (literally, 'gut-breathing') hemichordates, are marine invertebrates that share features with echinoderms and chordates. Together, these three phyla comprise the deuterostomes. Here we report the draft genome sequences of two acorn worms, Saccoglossus kowalevskii and Ptychodera flava. By comparing them with diverse bilaterian genomes, we identify shared traits that were probably inherited from the last common deuterostome ancestor, and then explore evolutionary trajectories leading from this ancestor to hemichordates, echinoderms and chordates. The hemichordate genomes exhibit extensive conserved synteny with amphioxus and other bilaterians, and deeply conserved non-coding sequences that are candidates for conserved gene-regulatory elements. Notably, hemichordates possess a deuterostome-specific genomic cluster of four ordered transcription factor genes, the expression of which is associated with the development of pharyngeal 'gill' slits, the foremost morphological innovation of early deuterostomes, and is probably central to their filter-feeding lifestyle. Comparative analysis reveals numerous deuterostome-specific gene novelties, including genes found in deuterostomes and marine microbes, but not other animals. The putative functions of these genes can be linked to physiological, metabolic and developmental specializations of the filter-feeding ancestor.


Assuntos
Cordados não Vertebrados/genética , Evolução Molecular , Genoma/genética , Animais , Cordados não Vertebrados/classificação , Sequência Conservada/genética , Equinodermos/classificação , Equinodermos/genética , Família Multigênica/genética , Filogenia , Transdução de Sinais , Sintenia/genética , Fator de Crescimento Transformador beta
4.
Parasitol Res ; 120(3): 949-962, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33426572

RESUMO

Foodborne zoonotic trematode (FZT) infections are common neglected tropical diseases in Southeast Asia. Their complicated life cycles involve freshwater snails as intermediate hosts. A cross-sectional study was conducted in Yen Bai and Thanh Hoa provinces in North and Central Vietnam, to investigate the diversity of cercariae of potential FZT and to construct the phylogenetic relationship of trematode cercariae based on the Internal Transcribed Spacer 2 (ITS2) region. Among 17 snail species collected from various habitats, 13 were infected by 10 cercarial groups among which parapleurolophocercous, pleurolophocercous, and echinostome cercariae were of zoonotic importance. The monophyletic tree separated cercarial sequences into different groups following the description of the cercariae families in which Haplorchidae, Opisthorchiidae, Echinochasmidae, and Echinostomatidae are important families of FZT. The overall prevalence was different among snail species and habitats and showed a seasonal trend. Parapleurolophocercous and echinostome cercariae emerged as the most common cercariae in snails in Yen Bai, while monostome, echinostome, and megalura cercariae were most common in Thanh Hoa. Using a molecular approach, we identified Parafossarulus striatulus as the first intermediate snail host of Clonorchis sinensis in Thac Ba Lake. Melanoides tuberculata and Bithynia fuchsiana were we identified preferred intermediate snail hosts of a diverse range of trematode species including intestinal flukes (i.e., Haplorchis pumilio and Echinochasmus japonicus) in Yen Bai and Thanh Hoa, respectively.


Assuntos
Doenças Transmitidas por Alimentos/parasitologia , Caramujos/parasitologia , Trematódeos/isolamento & purificação , Infecções por Trematódeos/parasitologia , Zoonoses/parasitologia , Animais , Cercárias/classificação , Cercárias/genética , Cercárias/crescimento & desenvolvimento , Cercárias/isolamento & purificação , Estudos Transversais , Doenças Transmitidas por Alimentos/epidemiologia , Água Doce/parasitologia , Filogenia , Prevalência , Caramujos/classificação , Trematódeos/classificação , Trematódeos/genética , Trematódeos/crescimento & desenvolvimento , Infecções por Trematódeos/epidemiologia , Vietnã/epidemiologia , Zoonoses/epidemiologia , Zoonoses/transmissão
5.
BMC Biol ; 18(1): 142, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33070780

RESUMO

BACKGROUND: The western flower thrips, Frankliniella occidentalis (Pergande), is a globally invasive pest and plant virus vector on a wide array of food, fiber, and ornamental crops. The underlying genetic mechanisms of the processes governing thrips pest and vector biology, feeding behaviors, ecology, and insecticide resistance are largely unknown. To address this gap, we present the F. occidentalis draft genome assembly and official gene set. RESULTS: We report on the first genome sequence for any member of the insect order Thysanoptera. Benchmarking Universal Single-Copy Ortholog (BUSCO) assessments of the genome assembly (size = 415.8 Mb, scaffold N50 = 948.9 kb) revealed a relatively complete and well-annotated assembly in comparison to other insect genomes. The genome is unusually GC-rich (50%) compared to other insect genomes to date. The official gene set (OGS v1.0) contains 16,859 genes, of which ~ 10% were manually verified and corrected by our consortium. We focused on manual annotation, phylogenetic, and expression evidence analyses for gene sets centered on primary themes in the life histories and activities of plant-colonizing insects. Highlights include the following: (1) divergent clades and large expansions in genes associated with environmental sensing (chemosensory receptors) and detoxification (CYP4, CYP6, and CCE enzymes) of substances encountered in agricultural environments; (2) a comprehensive set of salivary gland genes supported by enriched expression; (3) apparent absence of members of the IMD innate immune defense pathway; and (4) developmental- and sex-specific expression analyses of genes associated with progression from larvae to adulthood through neometaboly, a distinct form of maturation differing from either incomplete or complete metamorphosis in the Insecta. CONCLUSIONS: Analysis of the F. occidentalis genome offers insights into the polyphagous behavior of this insect pest that finds, colonizes, and survives on a widely diverse array of plants. The genomic resources presented here enable a more complete analysis of insect evolution and biology, providing a missing taxon for contemporary insect genomics-based analyses. Our study also offers a genomic benchmark for molecular and evolutionary investigations of other Thysanoptera species.


Assuntos
Genoma de Inseto , Características de História de Vida , Tisanópteros/fisiologia , Transcriptoma , Animais , Produtos Agrícolas , Comportamento Alimentar , Cadeia Alimentar , Imunidade Inata/genética , Percepção , Filogenia , Reprodução/genética , Tisanópteros/genética , Tisanópteros/imunologia
7.
BMC Genomics ; 21(1): 227, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171258

RESUMO

BACKGROUND: Halyomorpha halys (Stål), the brown marmorated stink bug, is a highly invasive insect species due in part to its exceptionally high levels of polyphagy. This species is also a nuisance due to overwintering in human-made structures. It has caused significant agricultural losses in recent years along the Atlantic seaboard of North America and in continental Europe. Genomic resources will assist with determining the molecular basis for this species' feeding and habitat traits, defining potential targets for pest management strategies. RESULTS: Analysis of the 1.15-Gb draft genome assembly has identified a wide variety of genetic elements underpinning the biological characteristics of this formidable pest species, encompassing the roles of sensory functions, digestion, immunity, detoxification and development, all of which likely support H. halys' capacity for invasiveness. Many of the genes identified herein have potential for biomolecular pesticide applications. CONCLUSIONS: Availability of the H. halys genome sequence will be useful for the development of environmentally friendly biomolecular pesticides to be applied in concert with more traditional, synthetic chemical-based controls.


Assuntos
Heterópteros/genética , Proteínas de Insetos/genética , Resistência a Inseticidas , Sequenciamento Completo do Genoma/métodos , Animais , Ecossistema , Transferência Genética Horizontal , Tamanho do Genoma , Heterópteros/classificação , Espécies Introduzidas , Filogenia
8.
Bioorg Med Chem ; 27(22): 115120, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31627975

RESUMO

Ribulose-1,5-biphosphate carboxylase/oxygenase (RuBisCO), an enzyme in the Calvin-Benson-Bassham cycle of photosynthesis, catalyzes the first step of CO2 fixation in plants, algae, and photosynthetic bacteria. Despite of the important function in the global carbon cycle, RuBisCO suffers from a slow reaction rate and a competing reaction with O2 which draw attentions to improve the enzyme efficiency. In this study, a RuBisCO dimer from Rhodospirillum rubrum was assembled on a DNA scaffold using a dimeric DNA binding protein as an adaptor. The enzyme assembly was characterized by atomic force microscopy and RuBisCO assembled on the DNA scaffold showed avid enzymatic activity with retaining its parent carboxylase function. To mimic the environment of the natural microcompartment in cyanobacterial carboxysome that encapsulate the second enzyme carbonic anhydrase (CA) with RuBisCO, RuBisCO was next co-assembled with CA on the DNA scaffold. Although the natural carboxysome assembly is believed to enhance the RuBisCO activity, the co-assembly of RuBisCO and CA reduced the RuBisCO activity, suggesting that the preferential CO2 dehydration by CA reduced the RuBisCO reaction rate. In line with the recent study, our results suggest that the proximity in the interenzyme distance of RuBisCO and CA is not the crucial determinant for the enhanced RuBisCO activity in carboxysome. The assembly of RuBisCO and CA on DNA scaffold provides a platform for further study on the spatial control of RuBisCO and associating enzymes.


Assuntos
Proteínas de Ligação a DNA/química , Ribulose-Bifosfato Carboxilase/química , Humanos
9.
BMC Biol ; 16(1): 54, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776407

RESUMO

BACKGROUND: Trichogrammatids are minute parasitoid wasps that develop within other insect eggs. They are less than half a millimeter long, smaller than some protozoans. The Trichogrammatidae are one of the earliest branching families of Chalcidoidea: a diverse superfamily of approximately half a million species of parasitoid wasps, proposed to have evolved from a miniaturized ancestor. Trichogramma are frequently used in agriculture, released as biological control agents against major moth and butterfly pests. Additionally, Trichogramma are well known for their symbiotic bacteria that induce asexual reproduction in infected females. Knowledge of the genome sequence of Trichogramma is a major step towards further understanding its biology and potential applications in pest control. RESULTS: We report the 195-Mb genome sequence of Trichogramma pretiosum and uncover signatures of miniaturization and adaptation in Trichogramma and related parasitoids. Comparative analyses reveal relatively rapid evolution of proteins involved in ribosome biogenesis and function, transcriptional regulation, and ploidy regulation. Chalcids also show loss or especially rapid evolution of 285 gene clusters conserved in other Hymenoptera, including many that are involved in signal transduction and embryonic development. Comparisons between sexual and asexual lineages of Trichogramma pretiosum reveal that there is no strong evidence for genome degradation (e.g., gene loss) in the asexual lineage, although it does contain a lower repeat content than the sexual lineage. Trichogramma shows particularly rapid genome evolution compared to other hymenopterans. We speculate these changes reflect adaptations to miniaturization, and to life as a specialized egg parasitoid. CONCLUSIONS: The genomes of Trichogramma and related parasitoids are a valuable resource for future studies of these diverse and economically important insects, including explorations of parasitoid biology, symbiosis, asexuality, biological control, and the evolution of miniaturization. Understanding the molecular determinants of parasitism can also inform mass rearing of Trichogramma and other parasitoids for biological control.


Assuntos
Evolução Molecular , Controle Biológico de Vetores , Vespas/classificação , Vespas/genética , Animais , Genômica , Mariposas/parasitologia , Filogenia , Vespas/patogenicidade , Sequenciamento Completo do Genoma/métodos
10.
BMC Genomics ; 19(1): 832, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30463532

RESUMO

BACKGROUND: Having conquered water surfaces worldwide, the semi-aquatic bugs occupy ponds, streams, lakes, mangroves, and even open oceans. The diversity of this group has inspired a range of scientific studies from ecology and evolution to developmental genetics and hydrodynamics of fluid locomotion. However, the lack of a representative water strider genome hinders our ability to more thoroughly investigate the molecular mechanisms underlying the processes of adaptation and diversification within this group. RESULTS: Here we report the sequencing and manual annotation of the Gerris buenoi (G. buenoi) genome; the first water strider genome to be sequenced thus far. The size of the G. buenoi genome is approximately 1,000 Mb, and this sequencing effort has recovered 20,949 predicted protein-coding genes. Manual annotation uncovered a number of local (tandem and proximal) gene duplications and expansions of gene families known for their importance in a variety of processes associated with morphological and physiological adaptations to a water surface lifestyle. These expansions may affect key processes associated with growth, vision, desiccation resistance, detoxification, olfaction and epigenetic regulation. Strikingly, the G. buenoi genome contains three insulin receptors, suggesting key changes in the rewiring and function of the insulin pathway. Other genomic changes affecting with opsin genes may be associated with wavelength sensitivity shifts in opsins, which is likely to be key in facilitating specific adaptations in vision for diverse water habitats. CONCLUSIONS: Our findings suggest that local gene duplications might have played an important role during the evolution of water striders. Along with these findings, the sequencing of the G. buenoi genome now provides us the opportunity to pursue exciting research opportunities to further understand the genomic underpinnings of traits associated with the extreme body plan and life history of water striders.


Assuntos
Genoma , Heterópteros/genética , Heterópteros/fisiologia , Proteínas de Insetos/genética , Adaptação Fisiológica , Animais , Evolução Molecular , Genômica , Heterópteros/classificação , Fenótipo , Filogenia
11.
Mol Biol Evol ; 34(8): 1838-1862, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460028

RESUMO

Chemosensory-related gene (CRG) families have been studied extensively in insects, but their evolutionary history across the Arthropoda had remained relatively unexplored. Here, we address current hypotheses and prior conclusions on CRG family evolution using a more comprehensive data set. In particular, odorant receptors were hypothesized to have proliferated during terrestrial colonization by insects (hexapods), but their association with other pancrustacean clades and with independent terrestrial colonizations in other arthropod subphyla have been unclear. We also examine hypotheses on which arthropod CRG family is most ancient. Thus, we reconstructed phylogenies of CRGs, including those from new arthropod genomes and transcriptomes, and mapped CRG gains and losses across arthropod lineages. Our analysis was strengthened by including crustaceans, especially copepods, which reside outside the hexapod/branchiopod clade within the subphylum Pancrustacea. We generated the first high-resolution genome sequence of the copepod Eurytemora affinis and annotated its CRGs. We found odorant receptors and odorant binding proteins present only in hexapods (insects) and absent from all other arthropod lineages, indicating that they are not universal adaptations to land. Gustatory receptors likely represent the oldest chemosensory receptors among CRGs, dating back to the Placozoa. We also clarified and confirmed the evolutionary history of antennal ionotropic receptors across the Arthropoda. All antennal ionotropic receptors in E. affinis were expressed more highly in males than in females, suggestive of an association with male mate-recognition behavior. This study is the most comprehensive comparative analysis to date of CRG family evolution across the largest and most speciose metazoan phylum Arthropoda.


Assuntos
Artrópodes/genética , Receptores Odorantes/genética , Animais , Células Quimiorreceptoras/fisiologia , Copépodes/genética , Crustáceos/genética , Bases de Dados de Ácidos Nucleicos , Evolução Molecular , Genoma/genética , Insetos/genética , Família Multigênica/genética , Filogenia
12.
Environ Sci Technol ; 52(10): 6009-6022, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29634279

RESUMO

Hyalella azteca is a cryptic species complex of epibenthic amphipods of interest to ecotoxicology and evolutionary biology. It is the primary crustacean used in North America for sediment toxicity testing and an emerging model for molecular ecotoxicology. To provide molecular resources for sediment quality assessments and evolutionary studies, we sequenced, assembled, and annotated the genome of the H. azteca U.S. Lab Strain. The genome quality and completeness is comparable with other ecotoxicological model species. Through targeted investigation and use of gene expression data sets of H. azteca exposed to pesticides, metals, and other emerging contaminants, we annotated and characterized the major gene families involved in sequestration, detoxification, oxidative stress, and toxicant response. Our results revealed gene loss related to light sensing, but a large expansion in chemoreceptors, likely underlying sensory shifts necessary in their low light habitats. Gene family expansions were also noted for cytochrome P450 genes, cuticle proteins, ion transporters, and include recent gene duplications in the metal sequestration protein, metallothionein. Mapping of differentially expressed transcripts to the genome significantly increased the ability to functionally annotate toxicant responsive genes. The H. azteca genome will greatly facilitate development of genomic tools for environmental assessments and promote an understanding of how evolution shapes toxicological pathways with implications for environmental and human health.


Assuntos
Anfípodes , Poluentes Químicos da Água , Animais , Ecotoxicologia , Sedimentos Geológicos , América do Norte , Testes de Toxicidade
13.
BMC Biol ; 15(1): 62, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28756775

RESUMO

BACKGROUND: The duplication of genes can occur through various mechanisms and is thought to make a major contribution to the evolutionary diversification of organisms. There is increasing evidence for a large-scale duplication of genes in some chelicerate lineages including two rounds of whole genome duplication (WGD) in horseshoe crabs. To investigate this further, we sequenced and analyzed the genome of the common house spider Parasteatoda tepidariorum. RESULTS: We found pervasive duplication of both coding and non-coding genes in this spider, including two clusters of Hox genes. Analysis of synteny conservation across the P. tepidariorum genome suggests that there has been an ancient WGD in spiders. Comparison with the genomes of other chelicerates, including that of the newly sequenced bark scorpion Centruroides sculpturatus, suggests that this event occurred in the common ancestor of spiders and scorpions, and is probably independent of the WGDs in horseshoe crabs. Furthermore, characterization of the sequence and expression of the Hox paralogs in P. tepidariorum suggests that many have been subject to neo-functionalization and/or sub-functionalization since their duplication. CONCLUSIONS: Our results reveal that spiders and scorpions are likely the descendants of a polyploid ancestor that lived more than 450 MYA. Given the extensive morphological diversity and ecological adaptations found among these animals, rivaling those of vertebrates, our study of the ancient WGD event in Arachnopulmonata provides a new comparative platform to explore common and divergent evolutionary outcomes of polyploidization events across eukaryotes.


Assuntos
Evolução Molecular , Duplicação Gênica , Genoma , Aranhas/genética , Animais , Feminino , Masculino , Sintenia
14.
Angew Chem Int Ed Engl ; 57(10): 2586-2591, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29341462

RESUMO

In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K+ channel proteins are assembled through zinc-finger protein (ZFP)-adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP-fused Kir3 channels and ZFP-based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K+ channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells.

15.
J Am Chem Soc ; 139(25): 8487-8496, 2017 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-28521084

RESUMO

Simultaneous formation of specific covalent linkages at nucleotides in given DNA sequences demand distinct orthogonal reactivity of DNA modification agents. Such highly specific reactions require well-balanced reactivity and affinity of the DNA modification agents. Conjugation of a sequence-specific DNA binding zinc finger protein and a self-ligating protein tag provides a modular adaptor that expedites formation of a covalent bond between the protein tag and a substrate-modified nucleotide at a specific DNA sequence. The modular adaptor stably locates a protein of interest fused to it at the target position on DNA scaffold in its functional form. Modular adaptors with orthogonal selectivity and fast reaction kinetics to specific DNA sequences enable site-specific location of different protein molecules simultaneously. Three different modular adaptors consisting of zinc finger proteins with distinct DNA sequence specificities and self-ligating protein tags with different substrate specificities achieved orthogonal covalent bond formation at respective sequences on the same DNA scaffold with an overall coassembly yield over 90%. Application of this unique set of orthogonal modular adaptors enabled construction of a cascade reaction of three enzymes from xylose metabolic pathway on DNA scaffold.


Assuntos
Sequência de Bases , Proteínas de Ligação a DNA/química , Desenho de Fármacos , Sequência de Bases/genética , Proteínas de Ligação a DNA/genética , Estrutura Molecular , Especificidade por Substrato
16.
Nature ; 469(7331): 529-33, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21270892

RESUMO

'Orang-utan' is derived from a Malay term meaning 'man of the forest' and aptly describes the southeast Asian great apes native to Sumatra and Borneo. The orang-utan species, Pongo abelii (Sumatran) and Pongo pygmaeus (Bornean), are the most phylogenetically distant great apes from humans, thereby providing an informative perspective on hominid evolution. Here we present a Sumatran orang-utan draft genome assembly and short read sequence data from five Sumatran and five Bornean orang-utan genomes. Our analyses reveal that, compared to other primates, the orang-utan genome has many unique features. Structural evolution of the orang-utan genome has proceeded much more slowly than other great apes, evidenced by fewer rearrangements, less segmental duplication, a lower rate of gene family turnover and surprisingly quiescent Alu repeats, which have played a major role in restructuring other primate genomes. We also describe a primate polymorphic neocentromere, found in both Pongo species, emphasizing the gradual evolution of orang-utan genome structure. Orang-utans have extremely low energy usage for a eutherian mammal, far lower than their hominid relatives. Adding their genome to the repertoire of sequenced primates illuminates new signals of positive selection in several pathways including glycolipid metabolism. From the population perspective, both Pongo species are deeply diverse; however, Sumatran individuals possess greater diversity than their Bornean counterparts, and more species-specific variation. Our estimate of Bornean/Sumatran speciation time, 400,000 years ago, is more recent than most previous studies and underscores the complexity of the orang-utan speciation process. Despite a smaller modern census population size, the Sumatran effective population size (N(e)) expanded exponentially relative to the ancestral N(e) after the split, while Bornean N(e) declined over the same period. Overall, the resources and analyses presented here offer new opportunities in evolutionary genomics, insights into hominid biology, and an extensive database of variation for conservation efforts.


Assuntos
Variação Genética , Genoma/genética , Pongo abelii/genética , Pongo pygmaeus/genética , Animais , Centrômero/genética , Cerebrosídeos/metabolismo , Cromossomos , Evolução Molecular , Feminino , Rearranjo Gênico/genética , Especiação Genética , Genética Populacional , Humanos , Masculino , Filogenia , Densidade Demográfica , Dinâmica Populacional , Especificidade da Espécie
17.
PLoS Genet ; 9(4): e1003443, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23593035

RESUMO

We report on results from whole-exome sequencing (WES) of 1,039 subjects diagnosed with autism spectrum disorders (ASD) and 870 controls selected from the NIMH repository to be of similar ancestry to cases. The WES data came from two centers using different methods to produce sequence and to call variants from it. Therefore, an initial goal was to ensure the distribution of rare variation was similar for data from different centers. This proved straightforward by filtering called variants by fraction of missing data, read depth, and balance of alternative to reference reads. Results were evaluated using seven samples sequenced at both centers and by results from the association study. Next we addressed how the data and/or results from the centers should be combined. Gene-based analyses of association was an obvious choice, but should statistics for association be combined across centers (meta-analysis) or should data be combined and then analyzed (mega-analysis)? Because of the nature of many gene-based tests, we showed by theory and simulations that mega-analysis has better power than meta-analysis. Finally, before analyzing the data for association, we explored the impact of population structure on rare variant analysis in these data. Like other recent studies, we found evidence that population structure can confound case-control studies by the clustering of rare variants in ancestry space; yet, unlike some recent studies, for these data we found that principal component-based analyses were sufficient to control for ancestry and produce test statistics with appropriate distributions. After using a variety of gene-based tests and both meta- and mega-analysis, we found no new risk genes for ASD in this sample. Our results suggest that standard gene-based tests will require much larger samples of cases and controls before being effective for gene discovery, even for a disorder like ASD.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Exoma , Estudo de Associação Genômica Ampla , Estudos de Casos e Controles , Criança , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Predisposição Genética para Doença , Variação Genética , Humanos , Controle da População , Análise de Sequência de DNA , Software
18.
Nature ; 452(7190): 949-55, 2008 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-18362917

RESUMO

Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes. Development in Tribolium is more representative of other insects than is Drosophila, a fact reflected in gene content and function. For example, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, some being expressed in the growth zone crucial for axial elongation in short-germ development. Systemic RNA interference in T. castaneum functions differently from that in Caenorhabditis elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control.


Assuntos
Genes de Insetos/genética , Genoma de Inseto/genética , Tribolium/genética , Animais , Composição de Bases , Padronização Corporal/genética , Sistema Enzimático do Citocromo P-450/genética , Elementos de DNA Transponíveis/genética , Crescimento e Desenvolvimento/genética , Humanos , Inseticidas/farmacologia , Neurotransmissores/genética , Oogênese/genética , Filogenia , Proteoma/genética , Interferência de RNA , Receptores Acoplados a Proteínas G/genética , Receptores Odorantes/genética , Sequências Repetitivas de Ácido Nucleico/genética , Paladar/genética , Telômero/genética , Tribolium/classificação , Tribolium/embriologia , Tribolium/fisiologia , Visão Ocular/genética
19.
N Engl J Med ; 362(13): 1181-91, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20220177

RESUMO

BACKGROUND: Whole-genome sequencing may revolutionize medical diagnostics through rapid identification of alleles that cause disease. However, even in cases with simple patterns of inheritance and unambiguous diagnoses, the relationship between disease phenotypes and their corresponding genetic changes can be complicated. Comprehensive diagnostic assays must therefore identify all possible DNA changes in each haplotype and determine which are responsible for the underlying disorder. The high number of rare, heterogeneous mutations present in all humans and the paucity of known functional variants in more than 90% of annotated genes make this challenge particularly difficult. Thus, the identification of the molecular basis of a genetic disease by means of whole-genome sequencing has remained elusive. We therefore aimed to assess the usefulness of human whole-genome sequencing for genetic diagnosis in a patient with Charcot-Marie-Tooth disease. METHODS: We identified a family with a recessive form of Charcot-Marie-Tooth disease for which the genetic basis had not been identified. We sequenced the whole genome of the proband, identified all potential functional variants in genes likely to be related to the disease, and genotyped these variants in the affected family members. RESULTS: We identified and validated compound, heterozygous, causative alleles in SH3TC2 (the SH3 domain and tetratricopeptide repeats 2 gene), involving two mutations, in the proband and in family members affected by Charcot-Marie-Tooth disease. Separate subclinical phenotypes segregated independently with each of the two mutations; heterozygous mutations confer susceptibility to neuropathy, including the carpal tunnel syndrome. CONCLUSIONS: As shown in this study of a family with Charcot-Marie-Tooth disease, whole-genome sequencing can identify clinically relevant variants and provide diagnostic information to inform the care of patients.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Estudos de Associação Genética , Genoma Humano , Adulto , Idoso , Idoso de 80 Anos ou mais , Códon sem Sentido , Feminino , Genes Recessivos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
20.
Blood ; 118(22): 5813-23, 2011 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-21860022

RESUMO

IL-36α (IL-1F6), IL-36ß (IL-1F8), and IL-36γ (IL-1F9) are members of the IL-1 family of cytokines. These cytokines bind to IL-36R (IL-1Rrp2) and IL-1RAcP, activating similar intracellular signals as IL-1, whereas IL-36Ra (IL-1F5) acts as an IL-36R antagonist (IL-36Ra). In this study, we show that both murine bone marrow-derived dendritic cells (BMDCs) and CD4(+) T lymphocytes constitutively express IL-36R and respond to IL-36α, IL-36ß, and IL-36γ. IL-36 induced the production of proinflammatory cytokines, including IL-12, IL-1ß, IL-6, TNF-α, and IL-23 by BMDCs with a more potent stimulatory effect than that of other IL-1 cytokines. In addition, IL-36ß enhanced the expression of CD80, CD86, and MHC class II by BMDCs. IL-36 also induced the production of IFN-γ, IL-4, and IL-17 by CD4(+) T cells and cultured splenocytes. These stimulatory effects were antagonized by IL-36Ra when used in 100- to 1000-fold molar excess. The immunization of mice with IL-36ß significantly and specifically promoted Th1 responses. Our data thus indicate a critical role of IL-36R ligands in the interface between innate and adaptive immunity, leading to the stimulation of T helper responses.


Assuntos
Células Dendríticas/efeitos dos fármacos , Ligantes , Receptores de Interleucina-1/agonistas , Receptores de Interleucina/agonistas , Linfócitos T/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/fisiologia , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/fisiologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Interleucina-1/farmacologia , Interleucina-1/fisiologia , Interleucinas/farmacologia , Interleucinas/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina/antagonistas & inibidores , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Linfócitos T/metabolismo , Linfócitos T/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA