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1.
NPJ Microgravity ; 10(1): 56, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744887

RESUMEN

The increasing accessibility of commercial and private space travel necessitates a profound understanding of its impact on human health. The NASA Open Science Data Repository (OSDR) provides transparent and FAIR access to biological studies, notably the SpaceX Inspiration4 (I4) mission, which amassed extensive data from civilian astronauts. This dataset encompasses omics and clinical assays, facilitating comprehensive research on space-induced biological responses. These data allow for multi-modal, longitudinal assessments, bridging the gap between human and model organism studies. Crucially, community-driven data standards established by NASA's OSDR Analysis Working Groups empower artificial intelligence and machine learning to glean invaluable insights, guiding future mission planning and health risk mitigation. This article presents a concise guide to access and analyze I4 data in OSDR, including programmatic access through GLOpenAPI. This pioneering effort establishes a precedent for post-mission health monitoring programs within space agencies, propelling research in the burgeoning field of commercial space travel's impact on human physiology.

2.
Precis Clin Med ; 7(1): pbae007, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38634106

RESUMEN

Background: The Inspiration4 (I4) mission, the first all-civilian orbital flight mission, investigated the physiological effects of short-duration spaceflight through a multi-omic approach. Despite advances, there remains much to learn about human adaptation to spaceflight's unique challenges, including microgravity, immune system perturbations, and radiation exposure. Methods: To provide a detailed genetics analysis of the mission, we collected dried blood spots pre-, during, and post-flight for DNA extraction. Telomere length was measured by quantitative PCR, while whole genome and cfDNA sequencing provided insight into genomic stability and immune adaptations. A robust bioinformatic pipeline was used for data analysis, including variant calling to assess mutational burden. Result: Telomere elongation occurred during spaceflight and shortened after return to Earth. Cell-free DNA analysis revealed increased immune cell signatures post-flight. No significant clonal hematopoiesis of indeterminate potential (CHIP) or whole-genome instability was observed. The long-term gene expression changes across immune cells suggested cellular adaptations to the space environment persisting months post-flight. Conclusion: Our findings provide valuable insights into the physiological consequences of short-duration spaceflight, with telomere dynamics and immune cell gene expression adapting to spaceflight and persisting after return to Earth. CHIP sequencing data will serve as a reference point for studying the early development of CHIP in astronauts, an understudied phenomenon as previous studies have focused on career astronauts. This study will serve as a reference point for future commercial and non-commercial spaceflight, low Earth orbit (LEO) missions, and deep-space exploration.

3.
Genome Res ; 31(7): 1269-1279, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34162698

RESUMEN

Telomeres are regions of repetitive nucleotide sequences capping the ends of eukaryotic chromosomes that protect against deterioration, and whose lengths can be correlated with age and adverse health risk factors. Yet, given their length and repetitive nature, telomeric regions are not easily reconstructed from short-read sequencing, thus making telomere sequencing, mapping, and variant resolution challenging problems. Recently, long-read sequencing, with read lengths measuring in hundreds of kilobase pairs, has made it possible to routinely read into telomeric regions and inspect their sequence structure. Here, we describe a framework for extracting telomeric reads from whole-genome single-molecule sequencing experiments, including de novo identification of telomere repeat motifs and repeat types, and also describe their sequence variation. We find that long, complex telomeric stretches and repeats can be accurately captured with long-read sequencing, observe extensive sequence heterogeneity of human telomeres, discover and localize noncanonical telomere sequence motifs (both previously reported, as well as novel), and validate them in short-read sequence data. These data reveal extensive intra- and inter-population diversity of repeats in telomeric haplotypes, reveal higher paternal inheritance of telomeric variants, and represent the first motif composition maps of multi-kilobase-pair human telomeric haplotypes across three distinct ancestries (Ashkenazi, Chinese, and Utah), which can aid in future studies of genetic variation, aging, and genome biology.

4.
Nucleic Acids Res ; 49(D1): D1515-D1522, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33080015

RESUMEN

The mission of NASA's GeneLab database (https://genelab.nasa.gov/) is to collect, curate, and provide access to the genomic, transcriptomic, proteomic and metabolomic (so-called 'omics') data from biospecimens flown in space or exposed to simulated space stressors, maximizing their utilization. This large collection of data enables the exploration of molecular network responses to space environments using a systems biology approach. We review here the various components of the GeneLab platform, including the new data repository web interface, and the GeneLab Online Data Entry (GEODE) web portal, which will support the expansion of the database in the future to include companion non-omics assay data. We discuss our design for GEODE, particularly how it promotes investigators providing more accurate metadata, reducing the curation effort required of GeneLab staff. We also introduce here a new GeneLab Application Programming Interface (API) specifically designed to support tools for the visualization of processed omics data. We review the outreach efforts by GeneLab to utilize the spaceflight data in the repository to generate novel discoveries and develop new hypotheses, including spearheading data analysis working groups, and a high school student training program. All these efforts are aimed ultimately at supporting precision risk management for human space exploration.


Asunto(s)
Bases de Datos Genéticas , Genoma , Programas Informáticos , Ingravidez , Animales , Astronautas , Bacterias/genética , Bacterias/metabolismo , Peces/genética , Peces/metabolismo , Regulación de la Expresión Génica , Humanos , Difusión de la Información , Insectos/genética , Insectos/metabolismo , Internet , Ratones , Nematodos/genética , Nematodos/metabolismo , Plantas/genética , Plantas/metabolismo , Vuelo Espacial , Simulación de Ingravidez
5.
iScience ; 23(12): 101844, 2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33376973

RESUMEN

Liquid biopsies based on cell-free DNA (cfDNA) or exosomes provide a noninvasive approach to monitor human health and disease but have not been utilized for astronauts. Here, we profile cfDNA characteristics, including fragment size, cellular deconvolution, and nucleosome positioning, in an astronaut during a year-long mission on the International Space Station, compared to his identical twin on Earth and healthy donors. We observed a significant increase in the proportion of cell-free mitochondrial DNA (cf-mtDNA) inflight, and analysis of post-flight exosomes in plasma revealed a 30-fold increase in circulating exosomes and patient-specific protein cargo (including brain-derived peptides) after the year-long mission. This longitudinal analysis of astronaut cfDNA during spaceflight and the exosome profiles highlights their utility for astronaut health monitoring, as well as cf-mtDNA levels as a potential biomarker for physiological stress or immune system responses related to microgravity, radiation exposure, and the other unique environmental conditions of spaceflight.

6.
Cell Rep ; 33(10): 108441, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33242404

RESUMEN

Understanding the impact of space exploration remains biologically elusive. Cell Press is dedicating this month to spaceflight (Afshinnekoo et al., 2020), with the open science NASA GeneLab database enabling the study revealing mitochondria as a key biological feature from spaceflight (da Silveira et al., 2020).


Asunto(s)
Difusión de la Información/métodos , Vuelo Espacial/métodos , Vuelo Espacial/tendencias , Bases de Datos Factuales , Humanos
7.
Cell Rep ; 33(10): 108435, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33242411

RESUMEN

Telomeres, repetitive terminal features of chromosomes essential for maintaining genome integrity, shorten with cell division, lifestyle factors and stresses, and environmental exposures, and so they provide a robust biomarker of health, aging, and age-related diseases. We assessed telomere length dynamics (changes over time) in three unrelated astronauts before, during, and after 1-year or 6-month missions aboard the International Space Station (ISS). Similar to our results for National Aeronautics and Space Administration's (NASA's) One-Year Mission twin astronaut (Garrett-Bakelman et al., 2019), significantly longer telomeres were observed during spaceflight for two 6-month mission astronauts. Furthermore, telomere length shortened rapidly after return to Earth for all three crewmembers and, overall, telomere length tended to be shorter after spaceflight than before spaceflight. Consistent with chronic exposure to the space radiation environment, signatures of persistent DNA damage responses were also detected, including mitochondrial and oxidative stress, inflammation, and telomeric and chromosomal aberrations, which together provide potential mechanistic insight into spaceflight-specific telomere elongation.


Asunto(s)
Daño del ADN/genética , Reparación del ADN/fisiología , Telómero/genética , Adulto , Astronautas , ADN/genética , ADN/efectos de la radiación , Roturas del ADN de Doble Cadena , Daño del ADN/efectos de la radiación , Reparación del ADN/genética , Reparación del ADN/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Medio Ambiente Extraterrestre , Femenino , Humanos , Masculino , Vuelo Espacial , Telómero/metabolismo , Telómero/efectos de la radiación , Factores de Tiempo , Ingravidez/efectos adversos
8.
Nature ; 569(7757): 576-580, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31092926

RESUMEN

Genetic and epigenetic intra-tumoral heterogeneity cooperate to shape the evolutionary course of cancer1. Chronic lymphocytic leukaemia (CLL) is a highly informative model for cancer evolution as it undergoes substantial genetic diversification and evolution after therapy2,3. The CLL epigenome is also an important disease-defining feature4,5, and growing populations of cells in CLL diversify by stochastic changes in DNA methylation known as epimutations6. However, previous studies using bulk sequencing methods to analyse the patterns of DNA methylation were unable to determine whether epimutations affect CLL populations homogeneously. Here, to measure the epimutation rate at single-cell resolution, we applied multiplexed single-cell reduced-representation bisulfite sequencing to B cells from healthy donors and patients with CLL. We observed that the common clonal origin of CLL results in a consistently increased epimutation rate, with low variability in the cell-to-cell epimutation rate. By contrast, variable epimutation rates across healthy B cells reflect diverse evolutionary ages across the trajectory of B cell differentiation, consistent with epimutations serving as a molecular clock. Heritable epimutation information allowed us to reconstruct lineages at high-resolution with single-cell data, and to apply this directly to patient samples. The CLL lineage tree shape revealed earlier branching and longer branch lengths than in normal B cells, reflecting rapid drift after the initial malignant transformation and a greater proliferative history. Integration of single-cell bisulfite sequencing analysis with single-cell transcriptomes and genotyping confirmed that genetic subclones mapped to distinct clades, as inferred solely on the basis of epimutation information. Finally, to examine potential lineage biases during therapy, we profiled serial samples during ibrutinib-associated lymphocytosis, and identified clades of cells that were preferentially expelled from the lymph node after treatment, marked by distinct transcriptional profiles. The single-cell integration of genetic, epigenetic and transcriptional information thus charts the lineage history of CLL and its evolution with therapy.


Asunto(s)
Linaje de la Célula , Epigénesis Genética , Evolución Molecular , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Secuencia de Bases , Relojes Biológicos , Linaje de la Célula/genética , Metilación de ADN , Epigenoma/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Leucemia Linfocítica Crónica de Células B/metabolismo , Tasa de Mutación , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcripción Genética
9.
Nat Commun ; 10(1): 579, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718479

RESUMEN

The DNA base modification N6-methyladenine (m6A) is involved in many pathways related to the survival of bacteria and their interactions with hosts. Nanopore sequencing offers a new, portable method to detect base modifications. Here, we show that a neural network can improve m6A detection at trained sequence contexts compared to previously published methods using deviations between measured and expected current values as each adenine travels through a pore. The model, implemented as the mCaller software package, can be extended to detect known or confirm suspected methyltransferase target motifs based on predictions of methylation at untrained contexts. We use PacBio, Oxford Nanopore, methylated DNA immunoprecipitation sequencing (MeDIP-seq), and whole-genome bisulfite sequencing data to generate and orthogonally validate methylomes for eight microbial reference species. These well-characterized microbial references can serve as controls in the development and evaluation of future methods for the identification of base modifications from single-molecule sequencing data.


Asunto(s)
Adenosina/análogos & derivados , Metilación de ADN/fisiología , Análisis de Secuencia de ADN/métodos , Adenosina/análisis , Algoritmos , Metilación de ADN/genética , Inmunoprecipitación , Programas Informáticos
10.
Genes (Basel) ; 10(1)2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30654561

RESUMEN

Islands have been used as model systems for studies of speciation and extinction since Darwin published his observations about finches found on the Galapagos. Amazon parrots inhabiting the Greater Antillean Islands represent a fascinating model of species diversification. Unfortunately, many of these birds are threatened as a result of human activity and some, like the Puerto Rican parrot, are now critically endangered. In this study we used a combination of de novo and reference-assisted assembly methods, integrating it with information obtained from related genomes to perform genome reconstruction of three amazon species. First, we used whole genome sequencing data to generate a new de novo genome assembly for the Puerto Rican parrot (Amazona vittata). We then improved the obtained assembly using transcriptome data from Amazona ventralis and used the resulting sequences as a reference to assemble the genomes Hispaniolan (A. ventralis) and Cuban (Amazona leucocephala) parrots. Finally, we, annotated genes and repetitive elements, estimated genome sizes and current levels of heterozygosity, built models of demographic history and provided interpretation of our findings in the context of parrot evolution in the Caribbean.


Asunto(s)
Especies en Peligro de Extinción , Genoma , Loros/genética , Animales , Islas , Loros/clasificación , Transcriptoma
11.
Gigascience ; 7(6)2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29718205

RESUMEN

Solenodons are insectivores that live in Hispaniola and Cuba. They form an isolated branch in the tree of placental mammals that are highly divergent from other eulipothyplan insectivores The history, unique biology, and adaptations of these enigmatic venomous species could be illuminated by the availability of genome data. However, a whole genome assembly for solenodons has not been previously performed, partially due to the difficulty in obtaining samples from the field. Island isolation and reduced numbers have likely resulted in high homozygosity within the Hispaniolan solenodon (Solenodon paradoxus). Thus, we tested the performance of several assembly strategies on the genome of this genetically impoverished species. The string graph-based assembly strategy seemed a better choice compared to the conventional de Bruijn graph approach due to the high levels of homozygosity, which is often a hallmark of endemic or endangered species. A consensus reference genome was assembled from sequences of 5 individuals from the southern subspecies (S. p. woodi). In addition, we obtained an additional sequence from 1 sample of the northern subspecies (S. p. paradoxus). The resulting genome assemblies were compared to each other and annotated for genes, with an emphasis on venom genes, repeats, variable microsatellite loci, and other genomic variants. Phylogenetic positioning and selection signatures were inferred based on 4,416 single-copy orthologs from 10 other mammals. We estimated that solenodons diverged from other extant mammals 73.6 million years ago. Patterns of single-nucleotide polymorphism variation allowed us to infer population demography, which supported a subspecies split within the Hispaniolan solenodon at least 300 thousand years ago.


Asunto(s)
Evolución Biológica , Secuencia Conservada/genética , Especies en Peligro de Extinción , Islas , Mamíferos/genética , Análisis de Secuencia de ADN/métodos , Animales , Cuba , Genoma , Heterocigoto , Especificidad de la Especie
12.
Neurotoxicol Teratol ; 66: 125-131, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29247702

RESUMEN

Epigenetic regulation plays an important role in development, at the embryonic stages and later during the lifespan. Some epigenetic marks are highly conserved throughout the lifespan whereas others are closely associated with specific age periods and/or particular environmental factors. Little is known about the dynamics of epigenetic regulation during childhood, especially during the period of rapid early development. Our study was aimed to determine whether the developmental program at the early stages of human development is accompanied by significant changes in the systems of genome regulation, specifically, by genome-wide changes in DNA methylation. Using a sequencing approach (MBD-seq) we investigated genome-wide DNA methylation patterns in the T-lymphocytes of three healthy toddlers at two timepoints within the second year of life. Pairwise comparison of the methylation patterns across the individuals and time points was conducted to determine common longitudinal changes in the DNA methylation patterns. Despite relatively high interindividual variability in their epigenetic profiles and the dynamics of these profiles during the second year of life, all children showed consistent changes in the DNA methylation patterns of genes involved in the control of the immune system and genes related to the development of the CNS. Thereby, we provide evidence that early development might be accompanied by epigenetic changes in specific functional groups of genes; many such epigenetic changes appear to be related to the rapid development of the CNS.


Asunto(s)
Desarrollo Infantil , Metilación de ADN/genética , Epigénesis Genética , Linfocitos T/metabolismo , Preescolar , Humanos , Lactante , Estudios Longitudinales , Masculino
13.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(5): 662-670, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-27159724

RESUMEN

Solenodons are insectivores found only in Hispaniola and Cuba, with a Mesozoic divergence date versus extant mainland mammals. Solenodons are the oldest lineage of living eutherian mammal for which a mitogenome sequence has not been reported. We determined complete mitogenome sequences for six Hispaniolan solenodons (Solenodon paradoxus) using next-generation sequencing. The solenodon mitogenomes were 16,454-16,457 bp long and carried the expected repertoire of genes. A mitogenomic phylogeny confirmed the basal position of solenodons relative to shrews and moles, with solenodon mitogenomes estimated to have diverged from those of other mammals ca. 78 Mya. Control region sequences of solenodons from the northern (n = 3) and southern (n = 5) Dominican Republic grouped separately in a network, with FST = 0.72 (p = 0.036) between north and south. This regional genetic divergence supports previous morphological and genetic reports recognizing northern (S. p. paradoxus) and southern (S. p. woodi) subspecies in need of separate conservation plans.


Asunto(s)
Eulipotyphla/clasificación , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mitocondrias/genética , Análisis de Secuencia de ADN/métodos , Animales , Eulipotyphla/genética , Evolución Molecular , Tamaño del Genoma , Genoma Mitocondrial , Filogenia
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