Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros

Banco de datos
Tipo de estudio
País/Región como asunto
Tipo del documento
Asunto de la revista
País de afiliación
Intervalo de año de publicación
1.
Nature ; 463(7283): 943-7, 2010 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-20164927

RESUMEN

The genetic structure of the indigenous hunter-gatherer peoples of southern Africa, the oldest known lineage of modern human, is important for understanding human diversity. Studies based on mitochondrial and small sets of nuclear markers have shown that these hunter-gatherers, known as Khoisan, San, or Bushmen, are genetically divergent from other humans. However, until now, fully sequenced human genomes have been limited to recently diverged populations. Here we present the complete genome sequences of an indigenous hunter-gatherer from the Kalahari Desert and a Bantu from southern Africa, as well as protein-coding regions from an additional three hunter-gatherers from disparate regions of the Kalahari. We characterize the extent of whole-genome and exome diversity among the five men, reporting 1.3 million novel DNA differences genome-wide, including 13,146 novel amino acid variants. In terms of nucleotide substitutions, the Bushmen seem to be, on average, more different from each other than, for example, a European and an Asian. Observed genomic differences between the hunter-gatherers and others may help to pinpoint genetic adaptations to an agricultural lifestyle. Adding the described variants to current databases will facilitate inclusion of southern Africans in medical research efforts, particularly when family and medical histories can be correlated with genome-wide data.


Asunto(s)
Población Negra/genética , Etnicidad/genética , Genoma Humano/genética , Pueblo Asiatico/genética , Exones/genética , Genética Médica , Humanos , Filogenia , Polimorfismo de Nucleótido Simple/genética , Sudáfrica/etnología , Población Blanca/genética
2.
Mycologia ; 116(2): 267-290, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38275281

RESUMEN

The entomopathogenic fungus Conoideocrella luteorostrata has recently been implicated in natural epizootics among exotic elongate hemlock scale (EHS) insects in Christmas tree farms in the eastern United States. Since 1913, C. luteorostrata has been reported from various plant feeding Hemiptera in the southeastern United States, but comprehensive morphological and phylogenetic studies of U.S. populations are lacking. The recovery of multiple strains of C. luteorostrata from mycosed EHS in North Carolina provided an opportunity to conduct pathogenicity assays and morphological and phylogenetic studies to investigate genus- and species-level boundaries among the Clavicipitaceae. Pathogenicity assays confirmed that C. luteorostrata causes mortality of EHS crawlers, an essential first step in developing this fungus as a biocontrol. Morphological studies revealed that conidia aligned with previous measurements of the Paecilomyces-like asexual state of C. luteorostrata, with conidiophore morphology consistent with historical observations. Additionally, a Hirsutella-like synanamorph was observed in select C. luteorostrata strains. In both a four-locus, 54-taxon Clavicipitaceae-wide phylogenetic analysis including D1-D2 domains of the nuclear 28S rRNA region (28S), elongation factor 1 alpha (EF1-α), DNA-directed RNA polymerase II subunit 1 (RPB1), and DNA-directed RNA polymerase II subunit 2 (RPB2) and a two-locus, 38-taxon (28S and EF1-α) phylogenetic analysis, all three Conoideocrella species were resolved as strongly supported monophyletic lineages across all loci and both methods (maximum likelihood and Bayesian inference) of phylogenetic inference except for 28S for C. tenuis. Despite the strong support for individual Conoideocrella species, none of the analyses supported the monophyly of Conoideocrella with the inclusion of Dussiella. Due to the paucity of RPB1 and RPB2 sequence data, EF1-α provided superior delimitation of intraspecies groupings for Conoideocrella and should be used in future studies. Further development of C. luteorostrata as a biocontrol against EHS will require additional surveys across diverse Hemiptera and expanded pathogenicity testing to clarify host range and efficacy of this fungus.


Asunto(s)
Hemípteros , Hypocreales , Animales , Estados Unidos , Filogenia , Teorema de Bayes , Hemípteros/microbiología , ARN Polimerasas Dirigidas por ADN/genética , North Carolina
3.
Artículo en Inglés | MEDLINE | ID: mdl-30701257

RESUMEN

Verticillium nonalfalfae, a cosmopolitan soil-borne phytopathogen, causes vascular wilt in agricultural crops and perennial woody plants. Select strains of V. nonalfalfae can cause lethal disease in the invasive tree Ailanthus altissima and several have since been utilized as a biological control (biocontrol) against this widespread invader. Here, we report the genome sequence and annotation of V. nonalfalfae strain VnAa140/NRRL 66861.

4.
PLoS One ; 5(10): e13432, 2010 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-20976145

RESUMEN

The ongoing emergence of human infections originating from wildlife highlights the need for better knowledge of the microbial community in wildlife species where traditional diagnostic approaches are limited. Here we evaluate the microbial biota in healthy mule deer (Odocoileus hemionus) by analyses of lymph node meta-transcriptomes. cDNA libraries from five individuals and two pools of samples were prepared from retropharyngeal lymph node RNA enriched for polyadenylated RNA and sequenced using Roche-454 Life Sciences technology. Protein-coding and 16S ribosomal RNA (rRNA) sequences were taxonomically profiled using protein and rRNA specific databases. Representatives of all bacterial phyla were detected in the seven libraries based on protein-coding transcripts indicating that viable microbiota were present in lymph nodes. Residents of skin and rumen, and those ubiquitous in mule deer habitat dominated classifiable bacterial species. Based on detection of both rRNA and protein-coding transcripts, we identified two new proteobacterial species; a Helicobacter closely related to Helicobacter cetorum in the Helicobacter pylori/Helicobacter acinonychis complex and an Acinetobacter related to Acinetobacter schindleri. Among viruses, a novel gamma retrovirus and other members of the Poxviridae and Retroviridae were identified. We additionally evaluated bacterial diversity by amplicon sequencing the hypervariable V6 region of 16S rRNA and demonstrate that overall taxonomic diversity is higher with the meta-transcriptomic approach. These data provide the most complete picture to date of the microbial diversity within a wildlife host. Our research advances the use of meta-transcriptomics to study microbiota in wildlife tissues, which will facilitate detection of novel organisms with pathogenic potential to human and animals.


Asunto(s)
Ciervos/microbiología , Perfilación de la Expresión Génica , Ganglios Linfáticos/microbiología , Animales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA