RESUMEN
Identifying functional enhancer elements in metazoan systems is a major challenge. Large-scale validation of enhancers predicted by ENCODE reveal false-positive rates of at least 70%. We used the pregrastrula-patterning network of Drosophila melanogaster to demonstrate that loss in accuracy in held-out data results from heterogeneity of functional signatures in enhancer elements. We show that at least two classes of enhancers are active during early Drosophila embryogenesis and that by focusing on a single, relatively homogeneous class of elements, greater than 98% prediction accuracy can be achieved in a balanced, completely held-out test set. The class of well-predicted elements is composed predominantly of enhancers driving multistage segmentation patterns, which we designate segmentation driving enhancers (SDE). Prediction is driven by the DNA occupancy of early developmental transcription factors, with almost no additional power derived from histone modifications. We further show that improved accuracy is not a property of a particular prediction method: after conditioning on the SDE set, naïve Bayes and logistic regression perform as well as more sophisticated tools. Applying this method to a genome-wide scan, we predict 1,640 SDEs that cover 1.6% of the genome. An analysis of 32 SDEs using whole-mount embryonic imaging of stably integrated reporter constructs chosen throughout our prediction rank-list showed >90% drove expression patterns. We achieved 86.7% precision on a genome-wide scan, with an estimated recall of at least 98%, indicating high accuracy and completeness in annotating this class of functional elements.
Asunto(s)
Proteínas de Drosophila , Embrión no Mamífero/embriología , Desarrollo Embrionario/fisiología , Elementos de Facilitación Genéticos/fisiología , Análisis de Secuencia de ADN , Factores de Transcripción , Animales , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Estudio de Asociación del Genoma Completo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Parental occupational exposures to pesticides, animals and organic dust have been associated with an increased risk of childhood cancer based mostly on case-control studies. We prospectively evaluated parental occupational exposures and risk of childhood leukemia and central nervous system (CNS) tumors in the International Childhood Cancer Cohort Consortium. We pooled data on 329,658 participants from birth cohorts in five countries (Australia, Denmark, Israel, Norway and United Kingdom). Parental occupational exposures during pregnancy were estimated by linking International Standard Classification of Occupations-1988 job codes to the ALOHA+ job exposure matrix. Risk of childhood (<15 years) acute lymphoblastic leukemia (ALL; n = 129), acute myeloid leukemia (AML; n = 31) and CNS tumors (n = 158) was estimated using Cox proportional hazards models to generate hazard ratios (HR) and 95% confidence intervals (CI). Paternal exposures to pesticides and animals were associated with increased risk of childhood AML (herbicides HR = 3.22, 95% CI = 0.97-10.68; insecticides HR = 2.86, 95% CI = 0.99-8.23; animals HR = 3.89, 95% CI = 1.18-12.90), but not ALL or CNS tumors. Paternal exposure to organic dust was positively associated with AML (HR = 2.38 95% CI = 1.12-5.07), inversely associated with ALL (HR = 0.55, 95% CI = 0.31-0.99) and not associated with CNS tumors. Low exposure prevalence precluded evaluation of maternal pesticide and animal exposures; we observed no significant associations with organic dust exposure. This first prospective analysis of pooled birth cohorts and parental occupational exposures provides evidence for paternal agricultural exposures as childhood AML risk factors. The different risks for childhood ALL associated with maternal and paternal organic dust exposures should be investigated further.
Asunto(s)
Neoplasias del Sistema Nervioso Central/epidemiología , Leucemia Mieloide Aguda/epidemiología , Exposición Materna/efectos adversos , Exposición Profesional/efectos adversos , Exposición Paterna/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Adolescente , Adulto , Animales , Animales Domésticos , Australia/epidemiología , Neoplasias del Sistema Nervioso Central/etiología , Niño , Preescolar , Dinamarca/epidemiología , Polvo , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Israel/epidemiología , Leucemia Mieloide Aguda/etiología , Masculino , Noruega/epidemiología , Plaguicidas/toxicidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Estudios Prospectivos , Factores de Riesgo , Reino Unido/epidemiología , Adulto JovenRESUMEN
The transcriptome is the readout of the genome. Identifying common features in it across distant species can reveal fundamental principles. To this end, the ENCODE and modENCODE consortia have generated large amounts of matched RNA-sequencing data for human, worm and fly. Uniform processing and comprehensive annotation of these data allow comparison across metazoan phyla, extending beyond earlier within-phylum transcriptome comparisons and revealing ancient, conserved features. Specifically, we discover co-expression modules shared across animals, many of which are enriched in developmental genes. Moreover, we use expression patterns to align the stages in worm and fly development and find a novel pairing between worm embryo and fly pupae, in addition to the embryo-to-embryo and larvae-to-larvae pairings. Furthermore, we find that the extent of non-canonical, non-coding transcription is similar in each organism, per base pair. Finally, we find in all three organisms that the gene-expression levels, both coding and non-coding, can be quantitatively predicted from chromatin features at the promoter using a 'universal model' based on a single set of organism-independent parameters.
Asunto(s)
Caenorhabditis elegans/genética , Drosophila melanogaster/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Animales , Caenorhabditis elegans/embriología , Caenorhabditis elegans/crecimiento & desarrollo , Cromatina/genética , Análisis por Conglomerados , Drosophila melanogaster/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica/genética , Histonas/metabolismo , Humanos , Larva/genética , Larva/crecimiento & desarrollo , Modelos Genéticos , Anotación de Secuencia Molecular , Regiones Promotoras Genéticas/genética , Pupa/genética , Pupa/crecimiento & desarrollo , ARN no Traducido/genética , Análisis de Secuencia de ARNRESUMEN
BACKGROUND: Virtually all anesthesiologists care for patients who sustain traumatic injuries; however, the frequency with which operative anesthesia care is provided to this specific patient population is unclear. We sought to better understand the degree to which anesthesia providers participate in operative trauma care and how this differs by trauma center designation (levels I-V), using data from a comprehensive, regional database-the Washington State Trauma Registry (WSTR). We also sought to specifically assess operative anesthesia care frequency vis a vis the American College of Surgeons guidelines for continuous anesthesiology coverage for Level II trauma center accreditation. METHODS: We conducted a retrospective analysis measuring the frequency of operative anesthesia care among patients enrolled in the WSTR. Univariate comparisons were made between trauma patients who had surgery during their admission and those who did not (medical management only). In addition, clinical factors associated with surgical intervention were measured. We also measured the average times from hospital admission to surgery and compared these times across trauma centers, grouped level I, II, and III-V. RESULTS: From 2004 to 2014, there were approximately 176,000 encounters meeting WSTR inclusion criteria. Approximately 60% of these trauma encounters included exposure to operative anesthesia during the admission. Among all surgical procedures during the trauma admission, approximately 33% occurred within a level I trauma center, 23% occurred within a level II trauma center, and 44% occurred in a trauma center with a III, IV, or V designation. The predominant procedure category during a trauma admission was orthopedic. The presence of hypotension on admission (P < .01), increasing injury severity score (P < .01) and higher emergency department Glasgow Coma Score (P < .01) were all associated with surgical intervention during the trauma hospitalization, after adjustment for potential confounders. In level I trauma centers, for general surgical procedures, the median time to surgery was 2.5 hours; in level II trauma centers, the median time was 1.7 hours. CONCLUSIONS: This study highlights the frequent role anesthesiologists play in caring for patients who sustain traumatic injuries, in trauma centers levels I-V. In level II trauma centers, in-house anesthesiology coverage might have benefit for those patients requiring surgery within 1 hour, whereas the former American College of Surgeons requirement of 30-minute response time for out-of-hospital anesthesiology coverage is likely sufficient to provide satisfactory care to patients requiring surgery within 3 hours. Whether the increased cost of such in-house anesthesiology coverage at level II trauma centers is justified by its clinical benefit remains an unanswered question.
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Anestesia/tendencias , Anestesiólogos/tendencias , Cuidados Intraoperatorios/tendencias , Grupo de Atención al Paciente/tendencias , Pautas de la Práctica en Medicina/tendencias , Heridas y Lesiones/cirugía , Adulto , Anciano , Anestesia/efectos adversos , Femenino , Humanos , Cuidados Intraoperatorios/efectos adversos , Masculino , Persona de Mediana Edad , Quirófanos , Tempo Operativo , Rol del Médico , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Cirujanos , Factores de Tiempo , Centros Traumatológicos , Resultado del Tratamiento , WashingtónRESUMEN
Alternative splicing is regulated by RNA binding proteins (RBPs) that recognize pre-mRNA sequence elements and activate or repress adjacent exons. Here, we used RNA interference and RNA-seq to identify splicing events regulated by 56 Drosophila proteins, some previously unknown to regulate splicing. Nearly all proteins affected alternative first exons, suggesting that RBPs play important roles in first exon choice. Half of the splicing events were regulated by multiple proteins, demonstrating extensive combinatorial regulation. We observed that SR and hnRNP proteins tend to act coordinately with each other, not antagonistically. We also identified a cross-regulatory network where splicing regulators affected the splicing of pre-mRNAs encoding other splicing regulators. This large-scale study substantially enhances our understanding of recent models of splicing regulation and provides a resource of thousands of exons that are regulated by 56 diverse RBPs.
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Empalme Alternativo , Proteínas de Drosophila/genética , Drosophila/genética , Proteínas de Unión al ARN/genética , Factores Asociados con la Proteína de Unión a TATA/genética , Animales , Proteínas de Drosophila/metabolismo , Exones , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Interferencia de ARN , Precursores del ARN/genética , Precursores del ARN/metabolismo , Proteínas de Unión al ARN/metabolismo , Análisis de Secuencia de ARN , Factores Asociados con la Proteína de Unión a TATA/metabolismoRESUMEN
Drosophila melanogaster plays an important role in molecular, genetic, and genomic studies of heredity, development, metabolism, behavior, and human disease. The initial reference genome sequence reported more than a decade ago had a profound impact on progress in Drosophila research, and improving the accuracy and completeness of this sequence continues to be important to further progress. We previously described improvement of the 117-Mb sequence in the euchromatic portion of the genome and 21 Mb in the heterochromatic portion, using a whole-genome shotgun assembly, BAC physical mapping, and clone-based finishing. Here, we report an improved reference sequence of the single-copy and middle-repetitive regions of the genome, produced using cytogenetic mapping to mitotic and polytene chromosomes, clone-based finishing and BAC fingerprint verification, ordering of scaffolds by alignment to cDNA sequences, incorporation of other map and sequence data, and validation by whole-genome optical restriction mapping. These data substantially improve the accuracy and completeness of the reference sequence and the order and orientation of sequence scaffolds into chromosome arm assemblies. Representation of the Y chromosome and other heterochromatic regions is particularly improved. The new 143.9-Mb reference sequence, designated Release 6, effectively exhausts clone-based technologies for mapping and sequencing. Highly repeat-rich regions, including large satellite blocks and functional elements such as the ribosomal RNA genes and the centromeres, are largely inaccessible to current sequencing and assembly methods and remain poorly represented. Further significant improvements will require sequencing technologies that do not depend on molecular cloning and that produce very long reads.
Asunto(s)
Drosophila melanogaster/genética , Genoma , Animales , Mapeo Cromosómico , Cromosomas Artificiales Bacterianos , Biología Computacional , Mapeo Contig , Secuenciación de Nucleótidos de Alto Rendimiento , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Cromosomas Politénicos , Mapeo RestrictivoRESUMEN
Drosophila melanogaster is one of the most well studied genetic model organisms; nonetheless, its genome still contains unannotated coding and non-coding genes, transcripts, exons and RNA editing sites. Full discovery and annotation are pre-requisites for understanding how the regulation of transcription, splicing and RNA editing directs the development of this complex organism. Here we used RNA-Seq, tiling microarrays and cDNA sequencing to explore the transcriptome in 30 distinct developmental stages. We identified 111,195 new elements, including thousands of genes, coding and non-coding transcripts, exons, splicing and editing events, and inferred protein isoforms that previously eluded discovery using established experimental, prediction and conservation-based approaches. These data substantially expand the number of known transcribed elements in the Drosophila genome and provide a high-resolution view of transcriptome dynamics throughout development.
Asunto(s)
Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/genética , Transcripción Genética/genética , Empalme Alternativo/genética , Animales , Secuencia de Bases , Proteínas de Drosophila/genética , Drosophila melanogaster/embriología , Exones/genética , Femenino , Genes de Insecto/genética , Genoma de los Insectos/genética , Masculino , MicroARNs/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Isoformas de Proteínas/genética , Edición de ARN/genética , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Pequeño no Traducido/análisis , ARN Pequeño no Traducido/genética , Análisis de Secuencia , Caracteres SexualesRESUMEN
BACKGROUND: Parental occupational and childhood exposures to farm animals have been positively associated with childhood brain tumors, whereas associations with childhood leukemia are equivocal. The developing immune system may be influenced by allergen, virus, or other exposures from animal sources, which may contribute to childhood cancer incidence. METHODS: Incident cancers (acute lymphoblastic leukemia [ALL], acute myeloid leukemia [AML], central nervous system [CNS], peripheral nervous system [PNS]) for children aged 0-4 diagnosed between 2003 and 2008 were obtained from nine National Cancer Institute Surveillance, Epidemiology and End Results (SEER) registries and were linked to U.S. Census of Agriculture data from 2002 and 2007 by county of diagnosis. Animal densities (animal units [AU]/km2; one animal unit is 1000 pounds of animal weight) were estimated for hogs, cattle, chickens (layers and broilers, separately), equine (horses, ponies, mules, burros, donkeys), goats, sheep, turkeys, and total animals. Animal density was examined in models as both continuous (AU per km2) and categorical variables (quartiles). Animal operation densities (per km2) by size of operation (cattle, hogs, chickens, sheep) were modeled continuously. Rate ratios and 95% confidence intervals were estimated using Poisson regression. RESULTS: We found positive associations between AML and broiler chicken densities (RRper 10AU/km2 = 1.14, 95% CI = 1.02-1.26). ALL rates increased with densities of hog operations (RRper operation/100km2 = 1.06, 95% CI = 1.02-1.11). PNS cancer rates were inversely associated with layer chicken density (RRper log of AU/km2 = 0.94, 95% CI = 0.89-0.99). No association was found between any cancer type and densities of cattle, equine, or goats. CONCLUSIONS: Although limited by the ecologic study design, some of our findings are novel and should be examined in epidemiological studies with individual level data.
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Ganado , Neoplasias/epidemiología , Aves de Corral , Animales , Neoplasias del Sistema Nervioso Central/epidemiología , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Leucemia Mieloide Aguda/epidemiología , Masculino , Neoplasias del Sistema Nervioso Periférico/epidemiología , Densidad de Población , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Características de la Residencia , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Few studies have evaluated environmental chemical exposures in relation to ovarian cancer. We previously found an increased risk of ovarian cancer among postmenopausal women in Iowa associated with higher nitrate levels in public water supplies (PWS). However, elevated nitrate levels may reflect the presence of other agricultural chemicals, such as atrazine, one of the most commonly detected pesticides in Iowa PWS. METHODS: We evaluated the association between atrazine in drinking water and incident ovarian cancer (N=145, 1986-2010) among 13â 041 postmenopausal women in the Iowa Women's Health Study who used their PWS for ≥11â years as reported in 1989. Average levels of atrazine (1986-1987), nitrate-nitrogen (NO3-N, 1955-1988) and estimated levels of total trihalomethanes (TTHM, 1955-1988) from PWS monitoring data were linked to the participants' cities of residence. We computed HRs and 95% CIs by categories of the average atrazine level (not detected, ≤ or >0.37 parts per billion=median) using Cox proportional hazards regression adjusting for ovarian cancer risk factors. RESULTS: Atrazine was detected in water samples from 69 cities where 4155 women (32%) lived and levels were moderately correlated with NO3-N (ρ=0.35) and TTHM (ρ=0.24). Atrazine levels were not associated with ovarian cancer risk with or without adjusting for NO3-N and TTHM levels (p-trend=0.50 and 0.81, respectively). Further, there was no evidence for effect modification of the atrazine association by NO3-N or TTHM levels. CONCLUSIONS: In our study with low atrazine detection rates, we found no association between atrazine in PWS and postmenopausal ovarian cancer risk.
Asunto(s)
Atrazina/efectos adversos , Agua Potable/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Herbicidas/efectos adversos , Neoplasias Ováricas/inducido químicamente , Neoplasias Ováricas/epidemiología , Anciano , Atrazina/análisis , Agua Potable/análisis , Femenino , Humanos , Iowa/epidemiología , Persona de Mediana Edad , Nitratos/efectos adversos , Posmenopausia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Trihalometanos/efectos adversos , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua , Salud de la MujerRESUMEN
BACKGROUND: There is limited evidence for an association between agricultural pesticide exposure and certain types of childhood cancers. Numerous studies have evaluated exposure to pesticides and childhood cancer and found positive associations. However, few studies have examined the density of agricultural land use as a surrogate for residential exposure to agricultural pesticides and results are mixed. We examined the association of county level agricultural land use and the incidence of specific childhood cancers. METHODS: We linked county-level agricultural census data (2002 and 2007) and cancer incidence data for children ages 0-4 diagnosed between 2004 and 2008 from cancer registries in six Midwestern states. Crop density (percent of county area that was harvested) was estimated for total agricultural land, barley, dry beans, corn, hay, oats, sorghum, soybeans, sugar beets, and wheat. Rate ratios and 95% confidence intervals were estimated using generalized estimating equation Poisson regression models and were adjusted for race, sex, year of diagnosis, median household income, education, and population density. RESULTS: We found statistically significant exposure-response relationships for dry beans and total leukemias (RR per 1% increase in crop density = 1.09, 95% CI = 1.03-1.14) and acute lymphoid leukemias (ALL) (RR = 1.10, 95% CI = 1.04-1.16); oats and acute myeloid leukemias (AML) (RR = 2.03, 95% CI = 1.25, 3.28); and sugar beets and total leukemias (RR = 1.11, 95% CI = 1.04, 1.19) and ALL (RR = 1.11, 95% CI = 1.02, 1.21). State-level analyses revealed some additional positive associations for total leukemia and CNS tumors and differences among states for several crop density-cancer associations. However, some of these analyses were limited by low crop prevalence and low cancer incidence. CONCLUSIONS: Publicly available data sources not originally intended to be used for health research can be useful for generating hypotheses about environmental exposures and health outcomes. The associations observed in this study need to be confirmed by analytic epidemiologic studies using individual level exposure data and accounting for potential confounders that could not be taken into account in this ecologic study.
Asunto(s)
Neoplasias del Sistema Nervioso Central/epidemiología , Productos Agrícolas , Leucemia/epidemiología , Neoplasias del Sistema Nervioso Periférico/epidemiología , Neoplasias del Sistema Nervioso Central/etiología , Preescolar , Productos Agrícolas/clasificación , Femenino , Geografía , Humanos , Incidencia , Lactante , Recién Nacido , Leucemia/etiología , Masculino , Medio Oeste de Estados Unidos/epidemiología , Neoplasias del Sistema Nervioso Periférico/etiología , Factores de RiesgoRESUMEN
BACKGROUND: Recent meta-analyses demonstrate an association between self-reported residential pesticide use and childhood leukemia risk. Self-reports may suffer from recall bias and provide information only on broad pesticide categories. We compared parental self-reported home and garden pest treatments to pesticides measured in carpet dust. METHODS: Parents of 277 children with leukemia and 306 controls in Northern and Central California (2001-2007) were asked about insect and weed treatments during the previous year. Carpet dust samples were analyzed for 47 pesticides. We present results for the 7 insecticides (carbaryl, propoxur, chlorpyrifos, diazinon, cyfluthrin, cypermethrin, permethrin), 5 herbicides (2,4-dichlorophenoxyacetic acid [2,4-D], chlorthal, dicamba, mecoprop, simazine), and 1 synergist (piperonyl butoxide) that were present in home and garden products during the study period and were detected in ≥25% of carpet dust samples. We constructed linear regression models for the relative change in pesticide concentrations associated with self-reported treatment of pest types in cases and controls separately and combined, adjusting for demographics, housing characteristics, and nearby agricultural pesticide applications. RESULTS: Several self-reported treatments were associated with pesticide concentrations in dust. For example, households with flea/tick treatments had 2.3 (95% Confidence Interval [CI]: 1.4, 3.7) times higher permethrin concentrations than households not reporting this treatment. Households reporting treatment for ants/cockroaches had 2.5 (95% CI: 1.5, 4.2) times higher cypermethrin levels than households not reporting this treatment. Weed treatment by a household member was associated with 1.9 (1.4, 2.6), 2.2 (1.6, 3.1), and 2.8 (2.1, 3.7) times higher dust concentrations of dicamba, mecoprop, and 2,4-D, respectively. Weed treatments by professional applicators were null/inversely associated with herbicide concentrations in dust. Associations were generally similar between cases and controls and were consistent with pesticide active ingredients in these products during the study time period. CONCLUSIONS: Consistency between self-reported pest treatments, concentrations in dust, and pesticides in products lends credibility to the exposure assessment methods and suggests that differential recall by case-control status is minimal.
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Polvo/análisis , Exposición a Riesgos Ambientales , Leucemia/epidemiología , Control de Plagas , Residuos de Plaguicidas/análisis , Adolescente , California/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Pisos y Cubiertas de Piso , Humanos , Lactante , Recién Nacido , Leucemia/inducido químicamente , Masculino , Control de Plagas/estadística & datos numéricos , Prevalencia , Medición de Riesgo , AutoinformeRESUMEN
Core promoters are critical regions for gene regulation in higher eukaryotes. However, the boundaries of promoter regions, the relative rates of initiation at the transcription start sites (TSSs) distributed within them, and the functional significance of promoter architecture remain poorly understood. We produced a high-resolution map of promoters active in the Drosophila melanogaster embryo by integrating data from three independent and complementary methods: 21 million cap analysis of gene expression (CAGE) tags, 1.2 million RNA ligase mediated rapid amplification of cDNA ends (RLM-RACE) reads, and 50,000 cap-trapped expressed sequence tags (ESTs). We defined 12,454 promoters of 8037 genes. Our analysis indicates that, due to non-promoter-associated RNA background signal, previous studies have likely overestimated the number of promoter-associated CAGE clusters by fivefold. We show that TSS distributions form a complex continuum of shapes, and that promoters active in the embryo and adult have highly similar shapes in 95% of cases. This suggests that these distributions are generally determined by static elements such as local DNA sequence and are not modulated by dynamic signals such as histone modifications. Transcription factor binding motifs are differentially enriched as a function of promoter shape, and peaked promoter shape is correlated with both temporal and spatial regulation of gene expression. Our results contribute to the emerging view that core promoters are functionally diverse and control patterning of gene expression in Drosophila and mammals.
Asunto(s)
Biología Computacional , Drosophila melanogaster/genética , Genoma de los Insectos/genética , Regiones Promotoras Genéticas , Regiones no Traducidas 3'/genética , Animales , Mapeo Cromosómico , Drosophila melanogaster/embriología , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/genética , Estudio de Asociación del Genoma Completo , Sitio de Iniciación de la TranscripciónRESUMEN
Synthetic biology is creating genetically engineered organisms at an increasing rate for many potentially valuable applications, but this potential comes with the risk of misuse or accidental release. To begin to address this issue, we have developed a system called GUARDIAN that can automatically detect signatures of engineering in DNA sequencing data, and we have conducted a blinded test of this system using a curated Test and Evaluation (T&E) data set. GUARDIAN uses an ensemble approach based on the guiding principle that no single approach is likely to be able to detect engineering with perfect accuracy. Critically, ensembling enables GUARDIAN to detect sequence inserts in 13 target organisms with a high degree of specificity that requires no subject matter expert (SME) review.
Asunto(s)
ADN , Análisis de Secuencia de ADN , ADN/genéticaRESUMEN
Transcription factors (TFs) play a key role in development and in cellular responses to the environment by activating or repressing the transcription of target genes in precise spatial and temporal patterns. In order to develop a catalog of target genes of Drosophila melanogaster TFs, the modERN consortium systematically knocked down the expression of TFs using RNAi in whole embryos followed by RNA-seq. We generated data for 45 TFs which have 18 different DNA-binding domains and are expressed in 15 of the 16 organ systems. The range of inactivation of the targeted TFs by RNAi ranged from log2fold change -3.52 to +0.49. The TFs also showed remarkable heterogeneity in the numbers of candidate target genes identified, with some generating thousands of candidates and others only tens. We present detailed analysis from five experiments, including those for three TFs that have been the focus of previous functional studies (ERR, sens, and zfh2) and two previously uncharacterized TFs (sens-2 and CG32006), as well as short vignettes for selected additional experiments to illustrate the utility of this resource. The RNA-seq datasets are available through the ENCODE DCC (http://encodeproject.org) and the Sequence Read Archive (SRA). TF and target gene expression patterns can be found here: https://insitu.fruitfly.org. These studies provide data that facilitate scientific inquiries into the functions of individual TFs in key developmental, metabolic, defensive, and homeostatic regulatory pathways, as well as provide a broader perspective on how individual TFs work together in local networks during embryogenesis.
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Proteínas de Drosophila , Drosophila , Animales , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Interferencia de ARN , Factores de Transcripción/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Proteínas de Unión al ADN/genéticaRESUMEN
Microbacterium sp. BDGP8 is a species of facultative anaerobic gram-positive bacterium of the family Microbacteriaceae. The complete genome consists of a single circular chromosome of 3,293,567 bp with a G + C content of 69.84% and two plasmids of 49,365 bp and 32,884 bp.
RESUMEN
Generating reference maps of interactome networks illuminates genetic studies by providing a protein-centric approach to finding new components of existing pathways, complexes, and processes. We apply state-of-the-art methods to identify binary protein-protein interactions (PPIs) for Drosophila melanogaster. Four all-by-all yeast two-hybrid (Y2H) screens of > 10,000 Drosophila proteins result in the 'FlyBi' dataset of 8723 PPIs among 2939 proteins. Testing subsets of data from FlyBi and previous PPI studies using an orthogonal assay allows for normalization of data quality; subsequent integration of FlyBi and previous data results in an expanded binary Drosophila reference interaction network, DroRI, comprising 17,232 interactions among 6511 proteins. We use FlyBi data to generate an autophagy network, then validate in vivo using autophagy-related assays. The deformed wings (dwg) gene encodes a protein that is both a regulator and a target of autophagy. Altogether, these resources provide a foundation for building new hypotheses regarding protein networks and function.
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Proteínas de Drosophila , Mapas de Interacción de Proteínas , Animales , Mapas de Interacción de Proteínas/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Drosophila/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Mapeo de Interacción de Proteínas/métodos , Técnicas del Sistema de Dos HíbridosRESUMEN
The gut microbiome produces vitamins, nutrients, and neurotransmitters, and helps to modulate the host immune system-and also plays a major role in the metabolism of many exogenous compounds, including drugs and chemical toxicants. However, the extent to which specific microbial species or communities modulate hazard upon exposure to chemicals remains largely opaque. Focusing on the effects of collateral dietary exposure to the widely used herbicide atrazine, we applied integrated omics and phenotypic screening to assess the role of the gut microbiome in modulating host resilience in Drosophila melanogaster. Transcriptional and metabolic responses to these compounds are sex-specific and depend strongly on the presence of the commensal microbiome. Sequencing the genomes of all abundant microbes in the fly gut revealed an enzymatic pathway responsible for atrazine detoxification unique to Acetobacter tropicalis. We find that Acetobacter tropicalis alone, in gnotobiotic animals, is sufficient to rescue increased atrazine toxicity to wild-type, conventionally reared levels. This work points toward the derivation of biotic strategies to improve host resilience to environmental chemical exposures, and illustrates the power of integrative omics to identify pathways responsible for adverse health outcomes.
Asunto(s)
Atrazina/toxicidad , Drosophila melanogaster/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Interacciones Microbiota-Huesped/efectos de los fármacos , Insecticidas/toxicidad , Acetobacter/genética , Acetobacter/metabolismo , Animales , Drosophila melanogaster/microbiología , Femenino , Inactivación Metabólica , MasculinoRESUMEN
Lactobacillus brevis Oregon-R-modENCODE strain BDGP6 was isolated from the gut of Drosophila melanogaster for functional host-microbial interaction studies. The bacterial chromosome is a single circular DNA molecule of 2,785,111 bp with a G+C content of 46%.
RESUMEN
Citrobacter freundii is a species of facultative anaerobic Gram-negative bacteria of the family Enterobacteriaceae The complete genome is composed of a single chromosomal circle of 4,957,773 bp with a G+C content of 52%.
RESUMEN
BACKGROUND: Spatial access to primary care has been associated with late-stage and fatal breast cancer, but less is known about its relation to outcomes of other screening-preventable cancers such as colorectal cancer. This population-based retrospective cohort study examined whether spatial access to primary care providers associates with colorectal cancer-specific survival. METHODS: Approximately 26 600 incident colorectal cancers diagnosed between 2000 and 2008 in adults residing in Cook County, Illinois were identified through the state cancer registry and georeferenced to the census tract of residence at diagnosis. An enhanced two-step floating catchment area method measured tract-level access to primary care physicians (PCPs) in the year of diagnosis using practice locations obtained from the American Medical Association. Vital status and underlying cause of death were determined using the National Death Index. Fine-Gray proportional subdistribution hazard models analyzed the association between tract-level PCP access scores and colorectal cancer-specific survival after accounting for tract-level socioeconomic status, case demographics, tumor characteristics, and other factors. RESULTS: Increased tract-level access to PCPs was associated with a lower risk of death from colorectal cancer (hazard ratio [HR], 95% confidence interval [CI]) = 0.87 [0.79, 0.96], P = .008, highest vs lowest quintile), especially among persons diagnosed with regional-stage tumors (HR, 95% CI = 0.80 [0.69, 0.93], P = .004, highest vs lowest quintile). CONCLUSIONS: Spatial access to primary care providers is a predictor of colorectal cancer-specific survival in Cook County, Illinois. Future research is needed to determine which areas within the cancer care continuum are most affected by spatial accessibility to primary care such as referral for screening, accessibility of screening and diagnostic testing, referral for treatment, and access to appropriate survivorship-related care.