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951.
952.
Chlo Baum Yu-Cheng Lin Alexey Fomenkov Brian
P Anton Lixin Chen Bo Yan Thomas C Evans Jr Richard
J Roberts Andrew
C Tolonen Laurence Ettwiller 《Nucleic acids research》2021,49(19):e113
DNA methylation is widespread amongst eukaryotes and prokaryotes to modulate gene expression and confer viral resistance. 5-Methylcytosine (m5C) methylation has been described in genomes of a large fraction of bacterial species as part of restriction-modification systems, each composed of a methyltransferase and cognate restriction enzyme. Methylases are site-specific and target sequences vary across organisms. High-throughput methods, such as bisulfite-sequencing can identify m5C at base resolution but require specialized library preparations and single molecule, real-time (SMRT) sequencing usually misses m5C. Here, we present a new method called RIMS-seq (rapid identification of methylase specificity) to simultaneously sequence bacterial genomes and determine m5C methylase specificities using a simple experimental protocol that closely resembles the DNA-seq protocol for Illumina. Importantly, the resulting sequencing quality is identical to DNA-seq, enabling RIMS-seq to substitute standard sequencing of bacterial genomes. Applied to bacteria and synthetic mixed communities, RIMS-seq reveals new methylase specificities, supporting routine study of m5C methylation while sequencing new genomes. 相似文献
953.
Nick G.C. Smith Robert Knight Laurence D. Hurst 《BioEssays : news and reviews in molecular, cellular and developmental biology》1999,21(8):697-703
In vertebrates it is often found that if one considers a group of genes clustered on a certain chromosome, then the homologues of those genes often form another cluster on a different chromosome. There are four explanations, not necessarily mutually exclusive, to explain how such homologous clusters appeared. Homologous clusters are expected at a low probability even if genes are distributed at random. The duplication of a subset of the genome might create homologous clusters, as would a duplication of the entire genome. Alternatively, it may be adaptive for certain combinations of genes to cluster, although clearly the genes must have duplicated prior to rearrangement into clusters. Molecular phylogenetics provides a means to examine the origins of homologous clusters, although it is difficult to discriminate between the different explanations using current data. However, with more extensive sequencing and mapping of vertebrate genomes, especially those of the early diverging chordates, it should soon become possible to resolve the origins of homologous clusters. BioEssays 21:697–703, 1999. © 1999 John Wiley & Sons, Inc. 相似文献
954.
Blubber cortisol qualitatively reflects circulating cortisol concentrations in bottlenose dolphins
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![点击此处可从《Marine Mammal Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Cory D. Champagne Nicholas M. Kellar Daniel E. Crocker Samuel K. Wasser Rebecca K. Booth Marisa L. Trego Dorian S. Houser 《Marine Mammal Science》2017,33(1):134-153
Stress hormones, released into circulation as a consequence of disturbance, are classically assayed from blood samples but may also be detected in a variety of matrices. Blubber and fecal samples can be remotely collected from free‐ranging cetaceans without the confounding hormone elevations associated with chase, capture, and handling required to collect blood samples. The relationship between cortisol concentrations in circulation with that of blubber and feces, however, is unknown. To assess these associations, we elevated cortisol by orally administering hydrocortisone for five days in five bottlenose dolphins. Voluntary blood and fecal samples were collected daily; blubber biopsies were collected on day one, just prior to hydrocortisone administration, and days three and five of hydrocortisone administration. We evaluated subsequent changes in several circulating stress hormones as well as cortisol and glucocorticoid metabolites in blubber and feces, respectively. There was a significant association between cortisol levels in serum and in blubber (F1,12.7 = 14.3, P < 0.01, mR2 = 0.57) despite substantial variability in blubber cortisol levels. Counterintuitively, fecal cortisol metabolite levels were inversely related to serum cortisol. The relationship between serum and blubber cortisol levels suggests blubber samples from remote sampling may be useful to detect stress loads in this species. 相似文献
955.
TgPL2, a patatin‐like phospholipase domain‐containing protein,is involved in the maintenance of apicoplast lipids homeostasis in Toxoplasma
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![点击此处可从《Molecular microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Maude F. Lévêque Laurence Berry Yoshiki Yamaryo‐Botté Hoa Mai Nguyen Marine Galera Cyrille Y. Botté Sébastien Besteiro 《Molecular microbiology》2017,105(1):158-174
Patatin‐like phospholipases are involved in numerous cellular functions, including lipid metabolism and membranes remodeling. The patatin‐like catalytic domain, whose phospholipase activity relies on a serine‐aspartate dyad and an anion binding box, is widely spread among prokaryotes and eukaryotes. We describe TgPL2, a novel patatin‐like phospholipase domain‐containing protein from the parasitic protist Toxoplasma gondii. TgPL2 is a large protein, in which the key motifs for enzymatic activity are conserved in the patatin‐like domain. Using immunofluorescence assays and immunoelectron microscopy analysis, we have shown that TgPL2 localizes to the apicoplast, a non‐photosynthetic plastid found in most apicomplexan parasites. This plastid hosts several important biosynthetic pathways, which makes it an attractive organelle for identifying new potential drug targets. We thus addressed TgPL2 function by generating a conditional knockdown mutant and demonstrated it has an essential contribution for maintaining the integrity of the plastid. In absence of TgPL2, the organelle is rapidly lost and remaining apicoplasts appear enlarged, with an abnormal accumulation of membranous structures, suggesting a defect in lipids homeostasis. More precisely, analyses of lipid content upon TgPL2 depletion suggest this protein is important for maintaining levels of apicoplast‐generated fatty acids, and also regulating phosphatidylcholine and lysophosphatidylcholine levels in the parasite. 相似文献
956.
Brigitte Gouesnard Sandra Negro Amélie Laffray Jeff Glaubitz Albrecht Melchinger Pedro Revilla Jesus Moreno-Gonzalez Delphine Madur Valérie Combes Christine Tollon-Cordet Jacques Laborde Dominique Kermarrec Cyril Bauland Laurence Moreau Alain Charcosset Stéphane Nicolas 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(10):2165-2189
Key message
Genotyping by sequencing is suitable for analysis of global diversity in maize. We showed the distinctiveness of flint maize inbred lines of interest to enrich the diversity of breeding programs.Abstract
Genotyping-by-sequencing (GBS) is a highly cost-effective procedure that permits the analysis of large collections of inbred lines. We used it to characterize diversity in 1191 maize flint inbred lines from the INRA collection, the European Cornfed association panel, and lines recently derived from landraces. We analyzed the properties of GBS data obtained with different imputation methods, through comparison with a 50 K SNP array. We identified seven ancestral groups within the Flint collection (dent, Northern flint, Italy, Pyrenees–Galicia, Argentina, Lacaune, Popcorn) in agreement with breeding knowledge. Analysis highlighted many crosses between different origins and the improvement of flint germplasm with dent germplasm. We performed association studies on different agronomic traits, revealing SNPs associated with cob color, kernel color, and male flowering time variation. We compared the diversity of both our collection and the USDA collection which has been previously analyzed by GBS. The population structure of the 4001 inbred lines confirmed the influence of the historical inbred lines (B73, A632, Oh43, Mo17, W182E, PH207, and Wf9) within the dent group. It showed distinctly different tropical and popcorn groups, a sweet-Northern flint group and a flint group sub-structured in Italian and European flint (Pyrenees–Galicia and Lacaune) groups. Interestingly, we identified several selective sweeps between dent, flint, and tropical inbred lines that co-localized with SNPs associated with flowering time variation. The joint analysis of collections by GBS offers opportunities for a global diversity analysis of maize inbred lines.957.
Shyamesh Kumar Hannah Laurence Michael A. Owston R. Mark Sharp Priscilla Williams Robert E. Lanford Gene B. Hubbard Edward J. Dick Jr. 《Journal of medical primatology》2017,46(5):271-290
We present the spontaneous pathological lesions identified as a result of necropsy or biopsy for 245 chimpanzees (Pan troglodytes) over a 35‐year period. A review of the pathology database was performed for all diagnoses on chimpanzees from 1980 to 2014. All morphologic diagnoses, associated system, organ, etiology, and demographic information were reviewed and analyzed. Cardiomyopathy was the most frequent lesion observed followed by hemosiderosis, hyperplasia, nematodiasis, edema, and hemorrhage. The most frequently affected systems were the gastrointestinal, cardiovascular, urogenital, respiratory, and lymphatic/hematopoietic systems. The most common etiology was undetermined, followed by degenerative, physiologic, neoplastic, parasitic, and bacterial. Perinatal and infant animals were mostly affected by physiologic etiologies and chimpanzee‐induced trauma. Bacterial and physiologic etiologies were more common in juvenile animals. Degenerative and physiologic (and neoplastic in geriatric animals) etiologies predominated in adult, middle aged, and geriatric chimpanzees. 相似文献
958.
959.
960.
Atomic Layer Deposition of Functional Layers for on Chip 3D Li‐Ion All Solid State Microbattery
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Manon Létiche Etienne Eustache Jeremy Freixas Arnaud Demortière Vincent De Andrade Laurence Morgenroth Pascal Tilmant François Vaurette David Troadec Pascal Roussel Thierry Brousse Christophe Lethien 《Liver Transplantation》2017,7(2)
Nowadays, millimeter scale power sources are key devices for providing autonomy to smart, connected, and miniaturized sensors. However, until now, planar solid state microbatteries do not yet exhibit a sufficient surface energy density. In that context, architectured 3D microbatteries appear therefore to be a good solution to improve the material mass loading while keeping small the footprint area. Beside the design itself of the 3D microbaterry, one important technological barrier to address is the conformal deposition of thin films (lithiated or not) on 3D structures. For that purpose, atomic layer deposition (ALD) technology is a powerful technique that enables conformal coatings of thin film on complex substrate. An original, robust, and highly efficient 3D scaffold is proposed to significantly improve the geometrical surface of miniaturized 3D microbattery. Four functional layers composing the 3D lithium ion microbattery stacking has been successfully deposited on simple and double microtubes 3D templates. In depth synchrotron X‐ray nanotomography and high angle annular dark field transmission electron microscope analyses are used to study the interface between each layer. For the first time, using ALD, anatase TiO2 negative electrode is coated on 3D tubes with Li3PO4 lithium phosphate as electrolyte, opening the way to all solid‐state 3D microbatteries. The surface capacity is significantly increased by the proposed topology (high area enlargement factor – “thick” 3D layer), from 3.5 μA h cm?2 for a planar layer up to 0.37 mA h cm?2 for a 3D thin film (105 times higher). 相似文献