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101.
Total duplication of the small single copy region in the angiosperm plastome: Rearrangement and inverted repeat instability in Asarum 下载免费PDF全文
Brandon T. Sinn Dylan D. Sedmak Lawrence M. Kelly John V. Freudenstein 《American journal of botany》2018,105(1):71-84
Premise of the Study
As more plastomes are assembled, it is evident that rearrangements, losses, intergenic spacer expansion and contraction, and syntenic breaks within otherwise functioning plastids are more common than was thought previously, and such changes have developed independently in disparate lineages. However, to date, the magnoliids remain characterized by their highly conserved plastid genomes (plastomes).Methods
Illumina HiSeq and MiSeq platforms were used to sequence the plastomes of Saruma henryi and those of representative species from each of the six taxonomic sections of Asarum. Sequenced plastomes were compared in a phylogenetic context provided by maximum likelihood and parsimony inferences made using an additional 18 publicly available plastomes from early‐diverging angiosperm lineages.Key Results
In contrast to previously published magnoliid plastomes and the newly sequenced Saruma henryi plastome published here, Asarum plastomes have undergone extensive disruption and contain extremely lengthy AT‐repeat regions. The entirety of the small single copy region (SSC) of A. canadense and A. sieboldii var. sieboldii has been incorporated into the inverted repeat regions (IR), and the SSC of A. delavayi is only 14 bp long. All sampled Asarum plastomes share an inversion of a large portion of the large single copy region (LSC) such that trnE‐UUC is adjacent to the LSC‐IR boundary.Conclusions
Plastome divergence in Asarum appears to be consistent with trends seen in highly rearranged plastomes of the monocots and eudicots. We propose that plastome instability in Asarum is due to repetitive motifs that serve as recombinatory substrates and reduce genome stability. 相似文献102.
Decoupled genomic elements and the evolution of partner quality in nitrogen‐fixing rhizobia 下载免费PDF全文
Benjamin R. Gordon Christie R. Klinger Dylan J. Weese Jennifer A. Lau Patricia V. Burke Bryn T. M. Dentinger Katy D. Heath 《Ecology and evolution》2016,6(5):1317-1327
Understanding how mutualisms evolve in response to a changing environment will be critical for predicting the long‐term impacts of global changes, such as increased N (nitrogen) deposition. Bacterial mutualists in particular might evolve quickly, thanks to short generation times and the potential for independent evolution of plasmids through recombination and/or HGT (horizontal gene transfer). In a previous work using the legume/rhizobia mutualism, we demonstrated that long‐term nitrogen fertilization caused the evolution of less‐mutualistic rhizobia. Here, we use our 63 previously isolated rhizobium strains in comparative phylogenetic and quantitative genetic analyses to determine the degree to which variation in partner quality is attributable to phylogenetic relationships among strains versus recent genetic changes in response to N fertilization. We find evidence of distinct evolutionary relationships between chromosomal and pSym genes, and broad similarity between pSym genes. We also find that nifD has a unique evolutionary history that explains much of the variation in partner quality, and suggest MoFe subunit interaction sites in the evolution of less‐mutualistic rhizobia. These results provide insight into the mechanisms behind the evolutionary response of rhizobia to long‐term N fertilization, and we discuss the implications of our results for the evolution of the mutualism. 相似文献
103.
Simon I. Hay Katherine E. Battle David M. Pigott David L. Smith Catherine L. Moyes Samir Bhatt John S. Brownstein Nigel Collier Monica F. Myers Dylan B. George Peter W. Gething 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1614)
The primary aim of this review was to evaluate the state of knowledge of the geographical distribution of all infectious diseases of clinical significance to humans. A systematic review was conducted to enumerate cartographic progress, with respect to the data available for mapping and the methods currently applied. The results helped define the minimum information requirements for mapping infectious disease occurrence, and a quantitative framework for assessing the mapping opportunities for all infectious diseases. This revealed that of 355 infectious diseases identified, 174 (49%) have a strong rationale for mapping and of these only 7 (4%) had been comprehensively mapped. A variety of ambitions, such as the quantification of the global burden of infectious disease, international biosurveillance, assessing the likelihood of infectious disease outbreaks and exploring the propensity for infectious disease evolution and emergence, are limited by these omissions. An overview of the factors hindering progress in disease cartography is provided. It is argued that rapid improvement in the landscape of infectious diseases mapping can be made by embracing non-conventional data sources, automation of geo-positioning and mapping procedures enabled by machine learning and information technology, respectively, in addition to harnessing labour of the volunteer ‘cognitive surplus’ through crowdsourcing. 相似文献
104.
105.
Drake PM Schilling B Niles RK Prakobphol A Li B Jung K Cho W Braten M Inerowicz HD Williams K Albertolle M Held JM Iacovides D Sorensen DJ Griffith OL Johansen E Zawadzka AM Cusack MP Allen S Gormley M Hall SC Witkowska HE Gray JW Regnier F Gibson BW Fisher SJ 《Journal of proteome research》2012,11(4):2508-2520
We used a lectin chromatography/MS-based approach to screen conditioned medium from a panel of luminal (less aggressive) and triple negative (more aggressive) breast cancer cell lines (n=5/subtype). The samples were fractionated using the lectins Aleuria aurantia (AAL) and Sambucus nigra agglutinin (SNA), which recognize fucose and sialic acid, respectively. The bound fractions were enzymatically N-deglycosylated and analyzed by LC-MS/MS. In total, we identified 533 glycoproteins, ~90% of which were components of the cell surface or extracellular matrix. We observed 1011 glycosites, 100 of which were solely detected in ≥3 triple negative lines. Statistical analyses suggested that a number of these glycosites were triple negative-specific and thus potential biomarkers for this tumor subtype. An analysis of RNaseq data revealed that approximately half of the mRNAs encoding the protein scaffolds that carried potential biomarker glycosites were up-regulated in triple negative vs luminal cell lines, and that a number of genes encoding fucosyl- or sialyltransferases were differentially expressed between the two subtypes, suggesting that alterations in glycosylation may also drive candidate identification. Notably, the glycoproteins from which these putative biomarker candidates were derived are involved in cancer-related processes. Thus, they may represent novel therapeutic targets for this aggressive tumor subtype. 相似文献
106.
Expanding on previous research investigating the link between dreams and attachment, participants in committed dating relationships were recruited to fill out dream diaries for 1 week. It was hypothesized that when dreaming about romantic partners (attachment figures), dream content would vary by attachment style, such that insecurely attached individuals would experience a different quality of dream, emotionally and cognitively. At Time 1, participants completed a self-report measure of attachment style, and then completed a dream diary at home each morning for 7 days. Dreams that contained romantic partners were coded by double-blind research assistants for emotional content, with a focus on attachment-related emotions and stressful expressions. Anxious-attached and avoidant-attached participants experienced significantly more stress and conflict, and scored significantly higher on specific emotions such as anxiety and jealousy in such dreams. Secure scores did not correlate with any specific or general emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
108.
Deangelis KM D'Haeseleer P Chivian D Fortney JL Khudyakov J Simmons B Woo H Arkin AP Davenport KW Goodwin L Chen A Ivanova N Kyrpides NC Mavromatis K Woyke T Hazen TC 《Standards in genomic sciences》2011,5(1):69-85
In an effort to discover anaerobic bacteria capable of lignin degradation, we isolated "Enterobacter lignolyticus" SCF1 on minimal media with alkali lignin as the sole source of carbon. This organism was isolated anaerobically from tropical forest soils collected from the Short Cloud Forest site in the El Yunque National Forest in Puerto Rico, USA, part of the Luquillo Long-Term Ecological Research Station. At this site, the soils experience strong fluctuations in redox potential and are net methane producers. Because of its ability to grow on lignin anaerobically, we sequenced the genome. The genome of "E. lignolyticus" SCF1 is 4.81 Mbp with no detected plasmids, and includes a relatively small arsenal of lignocellulolytic carbohydrate active enzymes. Lignin degradation was observed in culture, and the genome revealed two putative laccases, a putative peroxidase, and a complete 4-hydroxyphenylacetate degradation pathway encoded in a single gene cluster. 相似文献
109.
Gary C. du Moulin Zorina Pitkin Yuan-Jin Shen Evelyn Conti Jean Ko Stewart Carla Charles Dylan Hamilton 《Cytotechnology》1994,15(1-3):365-372
Somatic cell and gene therapy involve the application of biological technologies to an individual patient through the use of living cells which provide a therapeutic benefit (Aliski, 1991). Various forms of cellular and gene therapies are being developed and evaluated in an increasing number of clinical trials for congential and acquired disorders. The potential and progress of these therapeutic applications have resulted in an increasing effort by the Food and Drug Administration (FDA) to develop the regulatory framework under which these therapeutic approaches would insure safety and efficacy, the primary mandate of the FDA.Over five years ago Cellcor began to define the parameters, specifications, and conditions relevant to a Quality Assurance/Quality Control (QA/QC) program that has evolved to insure safety and maximize the efficacy of applications of the company'sex vivo technology, autolymphocyte therapy. Autolymphocyte therapy is an outpatient form of somatic cell immunotherapy based upon the infusion of T cells that have been activatedex vivo using a combination of previously generated autologous cytokines and an anti-CD3 monoclonal antibody.We have been able to demonstrate the feasibility for the safe, controlled, and consistent preparation and delivery of a cellular therapy by application of relevant GMP regulations. This presentation reviews aspects of this program and chronicles our experience which at present amounts to over 4400 infusions for over 700 patients. This program provides a high degree of assurance that a cellular therapy program can be carried out in a multisite mode involving hundreds of patients through the strict adherence to cGMP as set forth in existing regulations. It would be prudent that developers of cellular andex vivo gene therapies establish a similar cell processing and QA/QC infrastructure at an early developmental stage to optimize safety and reproducibility and facilitate regulatory review. 相似文献