Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nat Genet ; 51(6): 1052-1059, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31152161

RESUMO

Maize is one of the most important crops globally, and it shows remarkable genetic diversity. Knowledge of this diversity could help in crop improvement; however, gold-standard genomes have been elucidated only for modern temperate varieties. Here, we present a high-quality reference genome (contig N50 of 15.78 megabases) of the maize small-kernel inbred line, which is derived from a tropical landrace. Using haplotype maps derived from B73, Mo17 and SK, we identified 80,614 polymorphic structural variants across 521 diverse lines. Approximately 22% of these variants could not be detected by traditional single-nucleotide-polymorphism-based approaches, and some of them could affect gene expression and trait performance. To illustrate the utility of the diverse SK line, we used it to perform map-based cloning of a major effect quantitative trait locus controlling kernel weight-a key trait selected during maize improvement. The underlying candidate gene ZmBARELY ANY MERISTEM1d provides a target for increasing crop yields.


Assuntos
Estudos de Associação Genética , Genoma de Planta , Genômica , Fenótipo , Zea mays/genética , Biologia Computacional/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Endogamia , Anotação de Sequência Molecular , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Característica Quantitativa Herdável
2.
Biotechnol Lett ; 41(6-7): 867-872, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119429

RESUMO

OBJECTIVE: To construct recombinant Lactococcus lactis (L. lactis) expressing viral protein 1 (VP1) of enterovirus 71 (EV71) and evaluate its immunogenicity to be used as an oral vaccine in BALB/c mice. RESULTS: Recombinant L. lactis competent in secreting VP1 (~ 30 kDa) into the extracellular environment with the aid of the signal peptide Usp45 was produced. Enzyme-linked immunosorbent assay showed that significant VP1-specific antibody response including the production of both serum IgG and fecal IgA (p < 0.05) was elicited in BALB/c mice upon oral immunization with recombinant L. lactis. Moreover, in contrast to negative control, recombinant L. lactis induced adequate neutralizing antibodies in mouse sera (p < 0.05) as demonstrated in virus neutralization assay, whereas the presence of neutralizing antibodies in fecal samples was obvious but not significant (p > 0.05). CONCLUSIONS: Recombinant L. lactis expressing VP1 of EV71 has the potential to be used as an oral vaccine candidate. The findings may provide some preliminary evidences for further development of effective and needle-free EV71 vaccines.

3.
Nanoscale Res Lett ; 13(1): 392, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30515587

RESUMO

An optical diode structure with two dislocated parallel metallic gratings is proposed and investigated numerically. Dichroic optical diode transmission is realized in this structure, i.e., optical diode effect is observed in two wavebands corresponding to inverse transmission directions. In the structure, two parallel metallic gratings with different grating constants are separated by a dielectric slab in between. The first illuminated grating acts as a selector for exciting surface plasmons at a proper wavelength. The other grating acts as an emitter to realize optical transmission. When the incident direction is reversed, the roles of two gratings exchange and surface plasmons are excited at another wavelength. In dichroic transmission wavebands, the optical diode structure exhibits extraordinary transmission and possesses high optical isolation up to 1. Furthermore, the operating wavebands can be modulated by changing structure parameters.

4.
BMC Pulm Med ; 18(1): 150, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30189886

RESUMO

BACKGROUND: Associations between ambient air pollution and child health outcomes have been well documented in developed countries such as the United States; however, only a limited number of studies have been conducted in developing countries. This study aimed to explore the acute effects of five ambient air pollutants (inhalable particles [PM10], fine particles [PM2.5], sulfur dioxide [SO2], nitrogen dioxide [NO2] and 0zone [O3]) on children hospital outpatients with respiratory diseases in Shijiazhuang, China. METHODS: Three years (2013-2015) of daily data, including cause-specific respiratory outpatient records and the concentrations of five air pollutants, were collected to examine the short-term association between air pollution and children's respiratory diseases; using a quasi-Poisson regression generalized additive model. Stratified analyses by season and age were also performed. RESULTS: From 2013 to 2015, a total of 551,678 hospital outpatient records for children with respiratory diseases were collected in Shijiazhuang, China. A 10 µg/m3 increase in a two-day average concentration (lag01) of NO2, PM2.5, and SO2 corresponded to an increase of 0.66% (95% confidence interval [CI]: 0.30-1.03%), 0.13% (95% CI: 0.02-0.24%), and 0.33% (95% CI: 0.10-0.56%) in daily hospital outpatient visits for children with respiratory diseases, respectively. The effects were stronger in the transition season (April, May, September and October) than in other seasons (the hot season [June to August] and the cool season [November to March]). Furthermore, results indicated a generally stronger association in older (7-14 years of age) than younger children (< 7 years of age). CONCLUSIONS: This research found a significant association between ambient NO2, PM2.5, and SO2 levels and hospital outpatient visits in child with respiratory diseases in Shijiazhuang, China.

5.
J Org Chem ; 83(20): 12763-12774, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30240218

RESUMO

A Sc(OTf)3-catalyzed highly diastereoselective one-pot sequential [3 + 3] dipolar cycloaddition reaction of aldehyde or ketone, N-alkyl hydroxylamine, and spirocyclopropyl oxindole is developed, allowing facile construction of spirocyclic oxindole-tetrahydro-1,2-oxazines with sufficient structural diversity. The corresponding catalytic enantioselective one-pot protocol of aldehydes is also reported, affording the desired adducts in up to 97% ee. The biological evaluation of selected oxindole-based spirocyclic tetrahydro-1,2-oxazines revealed that they exerted cytotoxic effects on human prostate cancer cells with the capacity to inhibit NFκB signaling in prostate cancer cells.

6.
Integr Zool ; 13(5): 553-568, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29316314

RESUMO

Accurate individual identification is required to estimate survival rates in avian populations. For endangered species, non-invasive methods of obtaining individual identification, such as using molted feathers as a source of DNA for microsatellite markers, are preferred because of less disturbance, easy sample preparation and high efficiency. With the availability of many avian genomes, a few pipelines isolating genome-wide microsatellites have been published, but it is still a challenge to isolate microsatellites from the reference genome efficiently. Here, we have developed an integrated tool comprising a bioinformatic pipeline and experimental procedures for microsatellite isolation and validation based on the reference genome. We have identified over 95 000 microsatellite loci and established a system comprising 10 highly polymorphic markers (PIC value: 0.49-0.93, mean: 0.79) for an endangered species, saker falcon (Falco cherrug). These markers (except 1) were successfully amplified in 126 molted feathers, exhibiting high amplification success rates (83.9-99.7%), high quality index (0.90-0.97) and low allelic dropout rates (1-9.5%). To further assess the efficiency of this marker system in a population study, we identified individual sakers using these molted feathers (adult) and 146 plucked feathers (offspring). The use of parent and offspring samples enabled us to infer the genotype of missing samples (N = 28), and all adult genotypes were used to ascertain that breeding turnover is a useful proxy for survival estimation in sakers. Our study presents a cost-effective tool for microsatellite isolation based on publicly available reference genomes and demonstrates the power of this tool in estimating key parameters of avian population dynamics.


Assuntos
Espécies em Perigo de Extinção , Falconiformes/genética , Variação Genética , Genoma , Repetições de Microssatélites/genética , Animais
7.
Nat Commun ; 8(1): 1619, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-29158496

RESUMO

Optically active spirocyclic compounds play an important role in drug discovery, and new synthetic strategies for the efficient generation of spiro stereocenters are in much demand. Here we report a catalytic enantioselective cycloaddition using spirocyclic donor-acceptor cyclopropanes as a promising approach for the generation of spiro stereocenters. A diastereo- and enantioselective [3 + 3] cycloaddition of spirocyclopropyl oxindoles with both aldonitrones and ketonitrones is developed. The key to reaction development is the activation of spirocyclopropyl oxindoles by a suitable electron-withdrawing N-protecting group. This activation approach offers the promise of a general solution to enable spirocyclopropyl oxindoles as synthons for catalytic enantioselective synthesis of spirocyclic oxindoles featuring a C3 spiro stereocenter, a prominent structural motif in drugs and pharmaceutically active compounds. This protocol also constitutes the catalytic enantioselective reaction using unactivated achiral ketonitrones to construct tetrasubstituted carbon stereocenters.

8.
Gigascience ; 6(11): 1-11, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29048487

RESUMO

Coconut palm (Cocos nucifera,2n = 32), a member of genus Cocos and family Arecaceae (Palmaceae), is an important tropical fruit and oil crop. Currently, coconut palm is cultivated in 93 countries, including Central and South America, East and West Africa, Southeast Asia and the Pacific Islands, with a total growth area of more than 12 million hectares [1]. Coconut palm is generally classified into 2 main categories: "Tall" (flowering 8-10 years after planting) and "Dwarf" (flowering 4-6 years after planting), based on morphological characteristics and breeding habits. This Palmae species has a long growth period before reproductive years, which hinders conventional breeding progress. In spite of initial successes, improvements made by conventional breeding have been very slow. In the present study, we obtained de novo sequences of the Cocos nucifera genome: a major genomic resource that could be used to facilitate molecular breeding in Cocos nucifera and accelerate the breeding process in this important crop. A total of 419.67 gigabases (Gb) of raw reads were generated by the Illumina HiSeq 2000 platform using a series of paired-end and mate-pair libraries, covering the predicted Cocos nucifera genome length (2.42 Gb, variety "Hainan Tall") to an estimated ×173.32 read depth. A total scaffold length of 2.20 Gb was generated (N50 = 418 Kb), representing 90.91% of the genome. The coconut genome was predicted to harbor 28 039 protein-coding genes, which is less than in Phoenix dactylifera (PDK30: 28 889), Phoenix dactylifera (DPV01: 41 660), and Elaeis guineensis (EG5: 34 802). BUSCO evaluation demonstrated that the obtained scaffold sequences covered 90.8% of the coconut genome and that the genome annotation was 74.1% complete. Genome annotation results revealed that 72.75% of the coconut genome consisted of transposable elements, of which long-terminal repeat retrotransposons elements (LTRs) accounted for the largest proportion (92.23%). Comparative analysis of the antiporter gene family and ion channel gene families between C. nucifera and Arabidopsis thaliana indicated that significant gene expansion may have occurred in the coconut involving Na+/H+ antiporter, carnitine/acylcarnitine translocase, potassium-dependent sodium-calcium exchanger, and potassium channel genes. Despite its agronomic importance, C. nucifera is still under-studied. In this report, we present a draft genome of C. nucifera and provide genomic information that will facilitate future functional genomics and molecular-assisted breeding in this crop species.


Assuntos
Cocos/genética , Genoma de Planta , Anotação de Sequência Molecular
9.
Gigascience ; 6(10): 1-11, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29020749

RESUMO

Rhododendron delavayi Franch. is globally famous as an ornamental plant. Its distribution in southwest China covers several different habitats and environments. However, not much research had been conducted on Rhododendron spp. at the molecular level, which hinders understanding of its evolution, speciation, and synthesis of secondary metabolites, as well as its wide adaptability to different environments. Here, we report the genome assembly and gene annotation of R. delavayi var. delavayi (the second genome sequenced in the Ericaceae), which will facilitate the study of the family. The genome assembly will have further applications in genome-assisted cultivar breeding. The final size of the assembled R. delavayi var. delavayi genome (695.09 Mb) was close to the 697.94 Mb, estimated by k-mer analysis. A total of 336.83 gigabases (Gb) of raw Illumina HiSeq 2000 reads were generated from 9 libraries (with insert sizes ranging from 170 bp to 40 kb), achieving a raw sequencing depth of ×482.6. After quality filtering, 246.06 Gb of clean reads were obtained, giving ×352.55 coverage depth. Assembly using Platanus gave a total scaffold length of 695.09 Mb, with a contig N50 of 61.8 kb and a scaffold N50 of 637.83 kb. Gene prediction resulted in the annotation of 32 938 protein-coding genes. The genome completeness was evaluated by CEGMA and BUSCO and reached 95.97% and 92.8%, respectively. The gene annotation completeness was also evaluated by CEGMA and BUSCO and reached 97.01% and 87.4%, respectively. Genome annotation revealed that 51.77% of the R. delavayi genome is composed of transposable elements, and 37.48% of long terminal repeat elements (LTRs). The de novo assembled genome of R. delavayi var. delavayi (hereinafter referred to as R. delavayi) is the second genomic resource of the family Ericaceae and will provide a valuable resource for research on future comparative genomic studies in Rhododendron species. The availability of the R. delavayi genome sequence will hopefully provide a tool for scientists to tackle open questions regarding molecular mechanisms underlying environmental interactions in the genus Rhododendron, more accurately understand the evolutionary processes and systematics of the genus, facilitate the identification of genes encoding pharmaceutically important compounds, and accelerate molecular breeding to release elite varieties.


Assuntos
Genoma de Planta , Rhododendron/genética , China , Filogenia
10.
Arch Iran Med ; 20(4): 246-250, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28412830

RESUMO

BACKGROUND: EBOV outbreaks continue to threaten the world due to the absence of effective vaccines and therapeutics. Easy-to-use and rapid diagnostic tests for EBOV are highly desired for prevention and control of the EVD epidemic. METHODS: Escherichia coli expression system was used to express VP40 protein of Zaire Ebola virus (ZEBOV) as water-soluble protein upon optimization of temperature, time, and IPTG concentration. VP40 protein was purified through Ni-NTA affinity chromatography and applied to immunize rabbits for immunogenicity analysis. Rabbit polyclonal antibodies against VP40 protein was produced and antibody response was analyzed using Western blot, enzyme-linked immunosorbent assay (ELISA), and immunoperoxidase monolayer assay (IPMA). RESULTS: Recombinant full-length VP40 protein of ZEBOV was expressed in E. coli Rosetta (DE3) cells as water-soluble protein. Analysis of antibody responses showed that rabbit polyclonal antibodies against VP40 protein could react specifically with this E. coli-expressed protein in Western blot and ELISA, and antibody titers in ELISA reached 1:25600. Besides, the produced rabbit polyclonal antibodies bound to VP40 proteins eukaryotically expressed by transfecting pcDNA-eGFP-VP40 into BHK-21 cells in IPMA. CONCLUSION: These results show that the prokaryotically expressed VP40 protein has high immunogenicity and can be used as diagnostic antigen in ELISA and other immunoassays. The strategy used in this study might be a potential way for preparing diagnostic agents for prevention and control of exotic diseases.


Assuntos
Anticorpos Antivirais/sangue , Ebolavirus/isolamento & purificação , Proteínas da Matriz Viral/imunologia , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Escherichia coli/metabolismo , Feminino , Doença pelo Vírus Ebola/diagnóstico , Humanos , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas da Matriz Viral/biossíntese
11.
Arch Virol ; 162(6): 1625-1631, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28224252

RESUMO

Avian infectious bronchitis virus (IBV) is a member of the family Coronaviridae. A binding domain that mediates the attachment of the virus to its receptor has been identified in the S1 protein of prototype IBV strain M41. In this study, we identified this binding domain in a different strain, as well as the cellular proteins that interact with it. First, we expressed the S1N proteins (residues 19-270) of M41 and another isolate, SCZJ3, and compared the binding capacities of recombinant S1N-M41 and S1N-SCZJ3 to host tissues. Protein histochemistry showed that both S1N-M41 and S1N-SCZJ3 could bind to lung and kidney, and that recombinant S1N-SCZJ3 displayed a distinctive staining pattern in the proventriculus. Recombinant S1N-SCZJ3 was then employed to purify binding-associated proteins in lung, kidney, and proventriculus. Using an affinity chromatography assay, two common bands of about 60 kDa and 70 kDa were obtained from the total tissue proteins. These protein bands were identified by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) as protein disulfide isomerase (PDI) and heat shock protein 70 (HSP70). Finally, infection of chicken embryo kidney (CEK) cells by SCZJ3 was found to be inhibited by anti-HSP70 but not anti-PDI polyclonal antibody. These data indicate that HSP70 is part of the receptor complex of IBV and might help to understand the mechanism of S-mediated cell entry of IBV.


Assuntos
Proteínas Aviárias/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Vírus da Bronquite Infecciosa/metabolismo , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Linhagem Celular , Galinhas , Vírus da Bronquite Infecciosa/isolamento & purificação , Rim/química , Rim/citologia , Rim/metabolismo , Rim/virologia , Pulmão/química , Pulmão/metabolismo , Doenças das Aves Domésticas/virologia , Domínios e Motivos de Interação entre Proteínas , Receptores Virais/química , Receptores Virais/genética , Organismos Livres de Patógenos Específicos , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/isolamento & purificação , Internalização do Vírus
12.
Virus Genes ; 52(4): 509-20, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27108998

RESUMO

Recombination between infectious bronchitis viruses (IBVs), together with point mutations, insertions, and deletions, is thought to be responsible for the emergence of new IBV variants. SAIBK2 is a nephropathogenic strain isolated from layer flocks vaccinated with live attenuated H120 vaccine in Sichuan province, China in 2011. SAIBK2 causes severe kidney lesions and results in 50 % mortality in 30-day-old specific-pathogen-free chickens (with a dose of 10(5) EID50/0.1 mL SAIBK2 per chicken). The complete genome of SAIBK2 consists of 27669 nucleotides, excluding the poly-A tail at the 3' end. SAIBK2 has the highest identity to YX10 in terms of complete genome. Phylogenetic analysis of complete sequence showed that SAIBK2 belongs to the most dominant genotype in China. Comparison and recombination analyses with other IBV strains revealed that SAIBK2 may originate from recombination events among a YX10-, a YN-, and a Mass-like strain. Furthermore, whole gene 5 and parts of nsp 3, nsp 4, nsp 16, and N genes are involved in the recombination events, and the uptake of these regions from YN and Mass strains by SAIBK2 may increase its replication efficiency and be responsible for its increased virulence in specific-pathogen-free chickens.


Assuntos
Vírus da Bronquite Infecciosa/genética , Recombinação Genética/genética , Virulência/genética , Animais , Sequência de Bases , Galinhas/virologia , China , Infecções por Coronavirus/virologia , Genoma Viral/genética , Genótipo , Mutação/genética , Filogenia , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Vacinas Atenuadas/genética
13.
Biosci Biotechnol Biochem ; 80(3): 574-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26618736

RESUMO

To obtain adhesive and safe lactic acid bacteria (LAB) strains for expressing heterologous antigens, we screened LAB inhabitants in intestine of Tibetan chickens by analyzing their adhesion and safety properties and the selected LAB was engineered to express heterologous antigen (UTEpi C-A) based on chromosomal integration strategy. We demonstrated that a new Lactobacillu salivarius TCMM17 strain is strongly adhesive to chicken intestinal epithelial cells, contains no endogenous plasmids, is susceptible to tested antimicrobials, and shows no toxicities. In order to examine the potential of TCMM17 strain as heterogenous antigen delivering vehicle, we introduced a UTEpi C-A expression cassette in its chromosome by constructing a non-replicative plasmid (pORI280-UUTEpi C-AD). The recombinant TCMM17 strain (∆TCMM17) stably was found to keep the gene cassette through 50 generations, and successfully displayed EpiC encoded by the cassette on its surface. This work provides a universal platform for development of novel oral vaccines and expression of further antigens of avian pathogens.


Assuntos
Antígenos de Bactérias/genética , Cromossomos Bacterianos , Epitopos/genética , Lactobacillus/genética , Animais , Galinhas , Feminino , Lactobacillus/imunologia , Masculino
14.
Biotechnol Lett ; 38(2): 299-304, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26463372

RESUMO

OBJECTIVE: To assemble infectious bronchitis virus (IBV)-like particles bearing the recombinant spike protein and investigate the humoral immune responses in chickens. RESULTS: IBV virus-like particles (VLPs) were generated through the co-infection with three recombinant baculoviruses separately encoding M, E or the recombinant S genes. The recombinant S protein was sufficiently flexible to retain the ability to self-assemble into VLPs. The size and morphology of the VLPs were similar to authentic IBV particles. In addition, the immunogenicity of IBV VLPs had been investigated. The results demonstrated that the efficiency of the newly generated VLPs was comparable to that of the inactivated M41 viruses in eliciting IBV-specific antibodies and neutralizing antibodies in chickens via subcutaneous inoculation. CONCLUSIONS: This work provides basic information for the mechanism of IBV VLP formation and develops a platform for further designing IBV VLP-based vaccines against IBV or other viruses.


Assuntos
Vírus da Bronquite Infecciosa/metabolismo , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/metabolismo , Virossomos/metabolismo , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Baculoviridae , Galinhas , Vetores Genéticos , Vírus da Bronquite Infecciosa/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/ultraestrutura , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Virossomos/genética
15.
Biosci Biotechnol Biochem ; 79(8): 1287-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25832890

RESUMO

An indirect enzyme-linked immunosorbent assay (ELISA) method based on a novel multi-epitope antigen of S protein (SE) was developed for antibodies detection against infectious bronchitis virus (IBV). The multi-epitope antigen SE protein was designed by arranging three S gene fragments (166-247 aa, S1 gene; 501-515 aa, S1 gene; 8-30 aa, S2 gene) in tandem. It was identified to be approximately 32 kDa as a His-tagged fusion protein and can bind IBV positive serum by western blot analysis. The conditions of the SE-ELISA method were optimized. The optimal concentration of the coating antigen SE was 3.689 µg/mL and the dilution of the primary antibodies was identified as 1:1000 using a checkerboard titration. The cut-off OD450 value was established at 0.332. The relative sensitivity and specificity between the SE-ELISA and IDEXX ELISA kit were 92.38 and 89.83%, respectively, with an accuracy of 91.46%. This assay is sensitive and specific for detection of antibodies against IBV.


Assuntos
Anticorpos/imunologia , Epitopos/imunologia , Vírus da Bronquite Infecciosa/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Antígenos Virais/imunologia , Galinhas/imunologia , Ensaio de Imunoadsorção Enzimática , Vírus da Bronquite Infecciosa/imunologia
16.
Org Lett ; 17(4): 972-5, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25654189

RESUMO

A "one-pot" tandem substitution/Krapcho reaction is reported for the facile synthesis of α-fluorinated esters and sulfones, which utilizes the byproduct salt formed in the substitution step as an indispensible reagent to facilitate the Krapcho reaction step. This represents the first sustainable tandem reaction that internally recycles the waste salt formed in the upstream step as the reagent for the downstream step.

17.
Nat Genet ; 46(7): 701-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24929829

RESUMO

Trichuris (whipworm) infects 1 billion people worldwide and causes a disease (trichuriasis) that results in major socioeconomic losses in both humans and pigs. Trichuriasis relates to an inflammation of the large intestine manifested in bloody diarrhea, and chronic disease can cause malnourishment and stunting in children. Paradoxically, Trichuris of pigs has shown substantial promise as a treatment for human autoimmune disorders, including inflammatory bowel disease (IBD) and multiple sclerosis. Here we report whole-genome sequencing at ∼140-fold coverage of adult male and female T. suis and ∼80-Mb draft assemblies. We explore stage-, sex- and tissue-specific transcription of mRNAs and small noncoding RNAs.


Assuntos
Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Genoma Helmíntico , Interações Hospedeiro-Parasita/genética , Suínos/parasitologia , Tricuríase/genética , Trichuris/genética , Animais , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Suínos/genética , Tricuríase/parasitologia
18.
Nat Commun ; 4: 2433, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24045858

RESUMO

Tigers and their close relatives (Panthera) are some of the world's most endangered species. Here we report the de novo assembly of an Amur tiger whole-genome sequence as well as the genomic sequences of a white Bengal tiger, African lion, white African lion and snow leopard. Through comparative genetic analyses of these genomes, we find genetic signatures that may reflect molecular adaptations consistent with the big cats' hypercarnivorous diet and muscle strength. We report a snow leopard-specific genetic determinant in EGLN1 (Met39>Lys39), which is likely to be associated with adaptation to high altitude. We also detect a TYR260G>A mutation likely responsible for the white lion coat colour. Tiger and cat genomes show similar repeat composition and an appreciably conserved synteny. Genomic data from the five big cats provide an invaluable resource for resolving easily identifiable phenotypes evident in very close, but distinct, species.


Assuntos
Genoma/genética , Leões/genética , Panthera/genética , Tigres/genética , Adaptação Fisiológica/genética , Sequência de Aminoácidos , Animais , Variação Genética , Dados de Sequência Molecular , Mutação/genética , Densidade Demográfica , Sintenia/genética
19.
Artigo em Chinês | MEDLINE | ID: mdl-24044206

RESUMO

OBJECTIVE: To construct the recombinant baculovirus with NA gene of Influenza H1N1 virus. METHODS: Full-length NA gene of Influenza virus H1N1 (A/PR/8/34) was amplified by PCR and inserted into pFastBacdual vector to construct the recombinant baculovirus transfer vector pFBD-NA. Recombinant shuttle vectors rBacmid-NA was then obtained after transforming DH10B competent cells containing bacmid plasmids. After transfecting into sf9 cells, recombinant baculovirus rBac-NA was obtained. The rBac-NA genome was extracted and identified by PCR. NA protein expressed by recombinant baculovirus-infected sf9 cells was determined by IFA, Western Bolt and ELISA. RESULTS: PCR results proved that recombinant shuttle vectors rBacmid-NA was successfully constructed. NA protein was detected by IFA and showed strong specific green fluorescence on the surface of infected cells. NA protein was recognized by two polyclonal antibodies specific for NA in Western Blot. ELISA showed specific reaction of recombinant NA protein with mouse polyclonal antibody against influenza virus (PR8), indicating high antigenicity. CONCLUSION: Recombinant baculovirus rBac-NA that expresse NA protein of influenza virus was successfully constructed. This work provides a basis for further study on NA protein function and novel influenza vaccine development.


Assuntos
Baculoviridae/genética , Vírus da Influenza A Subtipo H1N1/genética , Neuraminidase/genética , Proteínas Recombinantes/biossíntese , Animais , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Vetores Genéticos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vacinas contra Influenza , Camundongos , Spodoptera
20.
Cell Res ; 23(9): 1091-105, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23917531

RESUMO

Crocodilians are diving reptiles that can hold their breath under water for long periods of time and are crepuscular animals with excellent sensory abilities. They comprise a sister lineage of birds and have no sex chromosome. Here we report the genome sequence of the endangered Chinese alligator (Alligator sinensis) and describe its unique features. The next-generation sequencing generated 314 Gb of raw sequence, yielding a genome size of 2.3 Gb. A total of 22 200 genes were predicted in Alligator sinensis using a de novo, homology- and RNA-based combined model. The genetic basis of long-diving behavior includes duplication of the bicarbonate-binding hemoglobin gene, co-functioning of routine phosphate-binding and special bicarbonate-binding oxygen transport, and positively selected energy metabolism, ammonium bicarbonate excretion and cardiac muscle contraction. Further, we elucidated the robust Alligator sinensis sensory system, including a significantly expanded olfactory receptor repertoire, rapidly evolving nerve-related cellular components and visual perception, and positive selection of the night vision-related opsin and sound detection-associated otopetrin. We also discovered a well-developed immune system with a considerable number of lineage-specific antigen-presentation genes for adaptive immunity as well as expansion of the tripartite motif-containing C-type lectin and butyrophilin genes for innate immunity and expression of antibacterial peptides. Multifluorescence in situ hybridization showed that alligator chromosome 3, which encodes DMRT1, exhibits significant synteny with chicken chromosome Z. Finally, population history analysis indicated population admixture 0.60-1.05 million years ago, when the Qinghai-Tibetan Plateau was uplifted.


Assuntos
Jacarés e Crocodilos/genética , Genoma/genética , Jacarés e Crocodilos/classificação , Jacarés e Crocodilos/metabolismo , Animais , Composição de Bases/genética , Sequência de Bases , Bicarbonatos/metabolismo , Transporte Biológico/genética , Elementos de DNA Transponíveis/genética , Metabolismo Energético/genética , Hemoglobinas/genética , Sistema Imunitário , Contração Muscular/genética , Visão Noturna/genética , Condutos Olfatórios/citologia , Opsinas/genética , Oxigênio/metabolismo , Análise de Sequência de DNA , Processos de Determinação Sexual/genética , Olfato/genética , Fatores de Transcrição/genética , Percepção Visual/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA