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1.
Immunity ; 46(6): 1073-1088.e6, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28636956

RESUMO

The development of stabilized recombinant HIV envelope trimers that mimic the virion surface molecule has increased enthusiasm for a neutralizing antibody (nAb)-based HIV vaccine. However, there is limited experience with recombinant trimers as immunogens in nonhuman primates, which are typically used as a model for humans. Here, we tested multiple immunogens and immunization strategies head-to-head to determine their impact on the quantity, quality, and kinetics of autologous tier 2 nAb development. A bilateral, adjuvanted, subcutaneous immunization protocol induced reproducible tier 2 nAb responses after only two immunizations 8 weeks apart, and these were further enhanced by a third immunization with BG505 SOSIP trimer. We identified immunogens that minimized non-neutralizing V3 responses and demonstrated that continuous immunogen delivery could enhance nAb responses. nAb responses were strongly associated with germinal center reactions, as assessed by lymph node fine needle aspiration. This study provides a framework for preclinical and clinical vaccine studies targeting nAb elicitation.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/uso terapêutico , Centro Germinativo/imunologia , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/terapia , HIV-1/imunologia , Animais , Células Cultivadas , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Centro Germinativo/virologia , Infecções por HIV/imunologia , Humanos , Imunização , Injeções Subcutâneas , Primatas , Multimerização Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
2.
BMC Plant Biol ; 23(1): 529, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37904124

RESUMO

BACKGROUND: In hexaploid wheat, quantitative trait loci (QTL) and meta-QTL (MQTL) analyses were conducted to identify genomic regions controlling resistance to cereal cyst nematode (CCN), Heterodera avenae. A mapping population comprising 149 RILs derived from the cross HUW 468 × C 306 was used for composite interval mapping (CIM) and inclusive composite interval mapping (ICIM). RESULTS: Eight main effect QTLs on three chromosomes (1B, 2A and 3A) were identified using two repeat experiments. One of these QTLs was co-localized with a previously reported wheat gene Cre5 for resistance to CCN. Seven important digenic epistatic interactions (PVE = 5% or more) were also identified, each involving one main effect QTL and another novel E-QTL. Using QTLs earlier reported in literature, two meta-QTLs were also identified, which were also used for identification of 57 candidate genes (CGs). Out of these, 29 CGs have high expression in roots and encoded the following proteins having a role in resistance to plant parasitic nematodes (PPNs): (i) NB-ARC,P-loop containing NTP hydrolase, (ii) Protein Kinase, (iii) serine-threonine/tyrosine-PK, (iv) protein with leucine-rich repeat, (v) virus X resistance protein-like, (vi) zinc finger protein, (vii) RING/FYVE/PHD-type, (viii) glycosyl transferase, family 8 (GT8), (ix) rubisco protein with small subunit domain, (x) protein with SANT/Myb domain and (xi) a protein with a homeobox. CONCLUSION: Identification and selection of resistance loci with additive and epistatic effect along with two MQTL and associated CGs, identified in the present study may prove useful for understanding the molecular basis of resistance against H. avenae in wheat and for marker-assisted selection (MAS) for breeding CCN resistant wheat cultivars.


Assuntos
Locos de Características Quantitativas , Tylenchoidea , Animais , Locos de Características Quantitativas/genética , Triticum/genética , Triticum/parasitologia , Melhoramento Vegetal , Fenótipo
3.
Mol Genet Genomics ; 298(3): 579-601, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36884084

RESUMO

Significant yield losses in major cereal-growing regions around the world have been linked to cereal cyst nematodes (Heterodera spp.). Identifying and deploying natural sources of resistance is of utmost importance due to increasing concerns associated with chemical methods over the years. We screened 141 diverse wheat genotypes collected from pan-Indian wheat cultivation states for nematode resistance over two years, alongside two resistant (Raj MR1, W7984 (M6)) and two susceptible (WH147, Opata M85) checks. We performed genome-wide association analysis using four single-locus models (GLM, MLM, CMLM, and ECMLM) and three multi-locus models (Blink, FarmCPU, and MLMM). Single locus models identified nine significant MTAs (-log10 (P) > 3.0) on chromosomes 2A, 3B, and 4B whereas, multi-locus models identified 11 significant MTAs on chromosomes 1B, 2A, 3B, 3D and 4B. Single and multi-locus models identified nine common significant MTAs. Candidate gene analysis identified 33 genes like F-box-like domain superfamily, Cytochrome P450 superfamily, Leucine-rich repeat, cysteine-containing subtype Zinc finger RING/FYVE/PHD-type, etc., having a putative role in disease resistance. Such genetic resources can help to reduce the impact of this disease on wheat production. Additionally, these results can be used to design new strategies for controlling the spread of H. avenae, such as the development of resistant varieties or the use of resistant cultivars. Finally, the obtained results can also be used to identify new sources of resistance to this pathogen and develop novel control methods.


Assuntos
Cistos , Tylenchoidea , Animais , Triticum/genética , Estudo de Associação Genômica Ampla , Grão Comestível/genética , Tylenchoidea/genética
4.
Mol Breed ; 42(10): 56, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37313017

RESUMO

We recently developed a database for hexaploid wheat QTL (WheatQTLdb; www.wheatqtldb.net), which included 11,552 QTL affecting various traits of economic importance. However, that database did not include valuable QTL from other wheat species and/or progenitors of hexaploid wheat. Therefore, an updated and improved version of wheat QTL database (WheatQTLdb V2.0) was developed, which now includes information on hexaploid wheat (Triticum aestivum) and the following seven other related species: T. durum, T. turgidum, T. dicoccoides, T. dicoccum, T. monococcum, T. boeoticum, and Aegilops tauschii. WheatQTLdb V2.0 includes a much-improved list of QTL, including 27,518 main effect QTL, 202 epistatic QTL, and 1321 metaQTL. This newly released WheatQTLdb V2.0 also has additional valuable options to search and choose the QTL, category-wise, and trait-wise data for their use in research or breeding programs.

5.
Physiol Mol Biol Plants ; 28(3): 651-668, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35465203

RESUMO

In the present study in wheat, GWAS was conducted for identification of marker trait associations (MTAs) for the following six grain morphology traits: (1) grain cross-sectional area (GCSA), (2) grain perimeter (GP), (3) grain length (GL), (4) grain width (GWid), (5) grain length-width ratio (GLWR) and (6) grain form-density (GFD). The data were recorded on a subset of spring wheat reference set (SWRS) comprising 225 diverse genotypes, which were genotyped using 10,904 SNPs and phenotyped for two consecutive years (2017-2018, 2018-2019). GWAS was conducted using five different models including two single-locus models (CMLM, SUPER), one multi-locus model (FarmCPU), one multi-trait model (mvLMM) and a model for Q x Q epistatic interactions. False discovery rate (FDR) [P value -log10(p) ≥ 5] and Bonferroni correction [P value -log10(p) ≥ 6] (corrected p value < 0.05) were applied to eliminate false positives due to multiple testing. This exercise gave 88 main effect and 29 epistatic MTAs after FDR and 13 main effect and 6 epistatic MTAs after Bonferroni corrections. MTAs obtained after Bonferroni corrections were further utilized for identification of 55 candidate genes (CGs). In silico expression analysis of CGs in different tissues at different parts of the seed at different developmental stages was also carried out. MTAs and CGs identified during the present study are useful addition to available resources for MAS to supplement wheat breeding programmes after due validation and also for future strategic basic research. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01164-w.

6.
Physiol Mol Biol Plants ; 28(3): 637-650, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35465199

RESUMO

Majority of cereals are deficient in essential micronutrients including grain iron (GFe) and grain zinc (GZn), which are therefore the subject of research involving biofortification. In the present study, 11 meta-QTLs (MQTLs) including nine novel MQTLs for GFe and GZn contents were identified in wheat. Eight of these 11 MQTLs controlled both GFe and GZn. The confidence intervals of the MQTLs were narrower (0.51-15.75 cM) relative to those of the corresponding QTLs (0.6 to 55.1 cM). Two ortho-MQTLs involving three cereals (wheat, rice and maize) were also identified. Results of MQTLs were also compared with the results of earlier genome wide association studies (GWAS). As many as 101 candidate genes (CGs) underlying MQTLs were also identified. Twelve of these CGs were prioritized; these CGs encoded proteins with important domains (zinc finger, RING/FYVE/PHD type, flavin adenine dinucleotide linked oxidase, etc.) that are involved in metal ion binding, heme binding, iron binding, etc. qRT-PCR analysis was conducted for four of these 12 prioritized CGs using genotypes which have differed for GFe and GZn. Significant differential expression in these genotypes was observed at 14 and 28 days after anthesis. The MQTLs/CGs identified in the present study may be utilized in marker-assisted selection (MAS) for improvement of GFe/GZn contents and also for understanding the molecular basis of GFe/GZn homeostasis in wheat. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01149-9.

7.
BMC Genomics ; 22(1): 597, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34353288

RESUMO

BACKGROUND: Bread wheat (Triticum aestivum L.) is one of the most important cereal food crops for the global population. Spike-layer uniformity (the consistency of the spike distribution in the vertical space)-related traits (SLURTs) are quantitative and have been shown to directly affect yield potential by modifying the plant architecture. Therefore, these parameters are important breeding targets for wheat improvement. The present study is the first genome-wide association study (GWAS) targeting SLURTs in wheat. In this study, a set of 225 diverse spring wheat accessions were used for multi-locus GWAS to evaluate SLURTs, including the number of spikes per plant (NSPP), spike length (SL), number of spikelets per spike (NSPS), grain weight per spike (GWPS), lowest tiller height (LTH), spike-layer thickness (SLT), spike-layer number (SLN) and spike-layer uniformity (SLU). RESULTS: In total, 136 significant marker trait associations (MTAs) were identified when the analysis was both performed individually and combined for two environments. Twenty-nine MTAs were detected in environment one, 48 MTAs were discovered in environment two and 59 MTAs were detected using combined data from the two environments. Altogether, 15 significant MTAs were found for five traits in one of the two environments, and four significant MTAs were detected for the two traits, LTH and SLU, in both environments i.e. E1, E2 and also in combined data from the two environments. In total, 279 candidate genes (CGs) were identified, including Chaperone DnaJ, ABC transporter-like, AP2/ERF, SWEET sugar transporter, as well as genes that have previously been associated with wheat spike development, seed development and grain yield. CONCLUSIONS: The MTAs detected through multi-locus GWAS will be useful for improving SLURTs and thus yield in wheat production through marker-assisted and genomic selection.


Assuntos
Estudo de Associação Genômica Ampla , Triticum , Pão , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas , Triticum/genética
8.
Mol Genet Genomics ; 296(5): 1051-1056, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34115214

RESUMO

During the last three decades, QTL analysis in wheat has been conducted for a variety of individual traits, so that thousands of QTL along with the linked markers, their genetic positions and contribution to phenotypic variation (PV) for concerned traits are now known. However, no exhaustive database for wheat QTL is currently available at a single platform. Therefore, the present database was prepared which is an exhaustive information resource for wheat QTL data from the published literature till May, 2020. QTL data from both interval mapping and genome-wide association studies (GWAS) have been included for the following classes of traits: (i) morphological traits, (ii) N and P use efficiency, (iii) traits for biofortification (Fe, K, Se, and Zn contents), (iv) tolerance to abiotic stresses including drought, water logging, heat stress, pre-harvest sprouting and salinity, (v) resistance to biotic stresses including those due to bacterial, fungal, nematode and insects, (vi) quality traits, and (vii) a variety of physiological traits, (viii) developmental traits, and (ix) yield and its related traits. For the preparation of the database, literature was searched for data on QTL/marker-trait associations (MTAs), curated and then assembled in the form of WheatQTLdb. The available information on metaQTL, epistatic QTL and candidate genes, wherever available, is also included in the database. Information on QTL in this WheatQTLdb includes QTL names, traits, associated markers, parental genotypes, crosses/mapping populations, association mapping panels and other useful information. To our knowledge, WheatQTLdb prepared by us is the largest collection of QTL (11,552), epistatic QTL (107) and metaQTL (330) data for hexaploid wheat to be used by geneticists and plant breeders for further studies involving fine mapping, cloning, and marker-assisted selection (MAS) during wheat breeding.


Assuntos
Bases de Dados Genéticas , Locos de Características Quantitativas , Triticum/genética , Epistasia Genética , Internet , Interface Usuário-Computador
9.
Theor Appl Genet ; 134(1): 1-35, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33136168

RESUMO

KEY MESSAGE: Knowledge of genetic variation, genetics, physiology/molecular basis and breeding (including biotechnological approaches) for biofortification and bioavailability for Zn, Fe and Se will help in developing nutritionally improved wheat. Biofortification of wheat cultivars for micronutrients is a priority research area for wheat geneticists and breeders. It is known that during breeding of wheat cultivars for productivity and quality, a loss of grain micronutrient contents occurred, leading to decline in nutritional quality of wheat grain. Keeping this in view, major efforts have been made during the last two decades for achieving biofortification and bioavailability of wheat grain for micronutrients including Zn, Fe and Se. The studies conducted so far included evaluation of gene pools for contents of not only grain micronutrients as above, but also for phytic acid (PA) or phytate and phytase, so that, while breeding for the micronutrients, bioavailability is also improved. For this purpose, QTL interval mapping and GWAS were carried out to identify QTLs/genes and associated markers that were subsequently used for marker-assisted selection (MAS) during breeding for biofortification. Studies have also been conducted to understand the physiology and molecular basis of biofortification, which also allowed identification of genes for uptake, transport and storage of micronutrients. Transgenics using transgenes have also been produced. The breeding efforts led to the development of at least a dozen cultivars with improved contents of grain micronutrients, although land area occupied by these biofortified cultivars is still marginal. In this review, the available information on different aspects of biofortification and bioavailability of micronutrients including Zn, Fe and Se in wheat has been reviewed for the benefit of those, who plan to start work or already conducting research in this area.


Assuntos
Biofortificação , Micronutrientes/análise , Triticum/química , Triticum/genética , 6-Fitase/genética , Disponibilidade Biológica , Alimentos Fortificados , Genes de Plantas , Ferro/análise , Valor Nutritivo , Ácido Fítico/análise , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Locos de Características Quantitativas , Selênio/análise , Zinco/análise
10.
Mol Breed ; 41(7): 46, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37309385

RESUMO

A genome-wide association study (GWAS) for 10 yield and yield component traits was conducted using an association panel comprising 225 diverse spring wheat genotypes. The panel was genotyped using 10,904 SNPs and evaluated for three years (2016-2019), which constituted three environments (E1, E2 and E3). Heritability for different traits ranged from 29.21 to 97.69%. Marker-trait associations (MTAs) were identified for each trait using data from each environment separately and also using BLUP values. Four different models were used, which included three single trait models (CMLM, FarmCPU, SUPER) and one multi-trait model (mvLMM). Hundreds of MTAs were obtained using each model, but after Bonferroni correction, only 6 MTAs for 3 traits were available using CMLM, and 21 MTAs for 4 traits were available using FarmCPU; none of the 525 MTAs obtained using SUPER could qualify after Bonferroni correction. Using BLUP, 20 MTAs were available, five of which also figured among MTAs identified for individual environments. Using mvLMM model, after Bonferroni correction, 38 multi-trait MTAs, for 15 different trait combinations were available. Epistatic interactions involving 28 pairs of MTAs were also available for seven of the 10 traits; no epistatic interactions were available for GNPS, PH, and BYPP. As many as 164 putative candidate genes (CGs) were identified using all the 50 MTAs (CMLM, 3; FarmCPU, 9; mvLMM, 6, epistasis, 21 and BLUP, 11 MTAs), which ranged from 20 (CMLM) to 66 (epistasis) CGs. In-silico expression analysis of CGs was also conducted in different tissues at different developmental stages. The information generated through the present study proved useful for developing a better understanding of the genetics of each of the 10 traits; the study also provided novel markers for marker-assisted selection (MAS) to be utilized for the development of wheat cultivars with improved agronomic traits. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01240-1.

11.
Theor Appl Genet ; 133(5): 1569-1602, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32253477

RESUMO

KEY MESSAGE: A review of the available literature on genetics of yield and its component traits, tolerance to abiotic stresses and biofortification should prove useful for future research in wheat in the genomics era. The work reviewed in this article mainly covers the available information on genetics of some important quantitative traits including yield and its components, tolerance to abiotic stresses (heat, drought, salinity and pre-harvest sprouting = PHS) and biofortification (Fe/Zn and phytate contents with HarvestPlus Program) in wheat. Major emphasis is laid on the recent literature on QTL interval mapping and genome-wide association studies, giving lists of known QTL and marker-trait associations. Candidate genes for different traits and the cloned and characterized genes for yield traits along with the molecular mechanism are also described. For each trait, an account of the present status of marker-assisted selection has also been included. The details of available results have largely been presented in the form of tables; some of these tables are included as supplementary files.


Assuntos
Adaptação Fisiológica , Biofortificação/métodos , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Triticum/crescimento & desenvolvimento , Proteínas de Plantas/genética , Triticum/genética , Triticum/metabolismo
12.
Kidney Int ; 95(4): 973-982, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30473139

RESUMO

The safety and efficacy of spironolactone is uncertain in end-stage renal disease. We randomized 129 maintenance hemodialysis patients to placebo (n=51) or spironolactone 12.5 mg (n=27), 25 mg (n=26), or 50 mg (n=25) daily for 36 weeks in a double-blind, placebo-controlled, multiple dosage trial to assess safety, tolerability and feasibility and to explore cardiovascular efficacy. The primary safety endpoints were hyperkalemia (potassium > 6.5 mEq/L) and hypotension requiring emergency department visit or hospitalization. Diastolic function was assessed by Doppler echocardiography. 125 participants (97%) completed dose escalation, with no significant difference in permanent study drug discontinuation between the groups (27.5% in placebo versus 16.7% in the combined spironolactone groups and 28% in the 50 mg group). Hyperkalemia frequency was similar between spironolactone and placebo (0.49 versus 0.50 events per patient-year) but demonstrated a significant linear trend due primarily to an increased event rate at the 50 mg dose (0.89 events per patient-year). The primary hypotension outcome was infrequent and similar with spironolactone and placebo (0.11 versus 0 events per patient-year). Gynecomastia was rare and did not differ significantly between groups. Change in diastolic function was similar with spironolactone and placebo. Spironolactone appears safe in carefully monitored maintenance hemodialysis patients, but did not affect cardiovascular parameters in this small study. Hyperkalemia occurs more frequently as dosage increases to 50 mg daily.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Hiperpotassemia/epidemiologia , Hipotensão/epidemiologia , Falência Renal Crônica/terapia , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Espironolactona/efeitos adversos , Adulto , Idoso , Aldosterona/metabolismo , Doenças Cardiovasculares/diagnóstico por imagem , Diástole/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ecocardiografia Doppler , Estudos de Viabilidade , Feminino , Ginecomastia/induzido quimicamente , Ginecomastia/epidemiologia , Humanos , Hiperpotassemia/sangue , Hiperpotassemia/induzido quimicamente , Hipotensão/induzido quimicamente , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Placebos/administração & dosagem , Placebos/efeitos adversos , Potássio/sangue , Diálise Renal , Espironolactona/administração & dosagem
13.
Inorg Chem ; 58(5): 3073-3089, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30789252

RESUMO

Pristine and Eu3+-doped BaZrO3 were synthesized via a solid-state reaction method, and the synthesized samples were systematically characterized. X-ray diffraction confirmed the formation of single and pure phases of cubic-structured BaZrO3. Extended X-ray absorption fine structure (EXAFS) spectroscopy revealed the site occupancy of Eu3+ and coordination environment around the different atomic sites. Photoluminescence (PL) excitation and emission spectra revealed the dominant absorption at 275 nm and a broad emission centered at 400 nm due to oxygen vacancies below the conduction band (CB). The PL emission intensity at 597 nm increased with increasing Eu3+ doping concentration; simultaneously, emission from the defect level decreased. This confirmed the efficient energy transfer from oxygen vacancies to Eu3+. Density functional theory was employed to calculate the density of states (DOS) to explain the mechanisms of the PL phenomenon. DOS also showed the presence of impurity states due to Eu3+ doping within the band-gap region. The coincidence of the oxygen vacancy state with Eu f state at the bottom of the CB confirmed the PL energy-transfer mechanisms from the oxygen vacancy to europium. The excited-state lifetime values of the 5D0 state decreased with increasing doping concentration due to the increase of the nonradiative transition rate. The internal quantum efficiency, small excited-state lifetime, and photometric parameters indicated that 3 mol % Eu3+-doped BaZrO3 can be a suitable candidate for the red-light-emitting device applications.

14.
Physiol Mol Biol Plants ; 25(2): 377-386, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30956421

RESUMO

Genetic diversity was assessed among 53 Indian garlic accessions using SSR markers. Initially, 24 SSR primer pairs were used for screening three selected garlic accessions. Out of 24 SSR primer pairs, 10 primer pairs which consistently showed good amplification and polymorphism were selected for DNA profiling. SSR primer pairs showed PIC values ranging from 0.30 to 0.99. Based on AMOVA we found that the greater part of the genetic diversity was expected due to intra population with 84% variation and only 16% of variation was due to among populations suggesting presence of genetic structure. The results of cluster analysis and principal component analysis largely correspond to each other. Population structure analysis revealed genetic differentiation of accessions. The results of present study revealed existence of significant variability in Indian garlic germplasm.

15.
Nature ; 491(7424): 406-12, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23151583

RESUMO

Characterization of human monoclonal antibodies is providing considerable insight into mechanisms of broad HIV-1 neutralization. Here we report an HIV-1 gp41 membrane-proximal external region (MPER)-specific antibody, named 10E8, which neutralizes ∼98% of tested viruses. An analysis of sera from 78 healthy HIV-1-infected donors demonstrated that 27% contained MPER-specific antibodies and 8% contained 10E8-like specificities. In contrast to other neutralizing MPER antibodies, 10E8 did not bind phospholipids, was not autoreactive, and bound cell-surface envelope. The structure of 10E8 in complex with the complete MPER revealed a site of vulnerability comprising a narrow stretch of highly conserved gp41-hydrophobic residues and a critical arginine or lysine just before the transmembrane region. Analysis of resistant HIV-1 variants confirmed the importance of these residues for neutralization. The highly conserved MPER is a target of potent, non-self-reactive neutralizing antibodies, suggesting that HIV-1 vaccines should aim to induce antibodies to this region of HIV-1 envelope glycoprotein.


Assuntos
Anticorpos Neutralizantes/metabolismo , Anticorpos Anti-HIV/metabolismo , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/fisiologia , Substituição de Aminoácidos , Anticorpos Neutralizantes/química , Especificidade de Anticorpos , Células Cultivadas , Células HEK293 , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/isolamento & purificação , Proteína gp41 do Envelope de HIV/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína
16.
Physiol Mol Biol Plants ; 24(3): 493-501, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29692556

RESUMO

ISSR (Inter simple sequence repeat) markers were used to assess the genetic diversity and population structure in 53 indigenous and exotic genotypes of gladiolus (Gladiolus hybridus Hort.). Molecular markers analysis showed PIC ranges from 0.42 (ISSR 861) to 0.99 (ISSR 855, ISSR 856 and ISSR 889) with an average 0.812, marker index ranged from 0.99 (ISSR 889) to 9.26 (ISSR 851) with an average 4.66 and resolving power of the primers ranged from 0.03 (ISSR 889) to 11.58 (ISSR 861) with an average value 3.80. The dendrogram based UPGMA clustering showed that all the 53 genotypes grouped into three main clusters. Nei's gene diversity (Na) varied from 0.929 to 1.717, effective number of alleles (Ne) varied from 1.262 to 1.369, Shannon's information index (I) ranged from 0.251 to 0.359 and gene diversity (He) was in the range from 0.167 to 0.229. Population structure analysis revealed three groups in which 32 genotypes were admixture types.

19.
J Virol ; 90(6): 2806-17, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26719252

RESUMO

UNLABELLED: Due to high viral diversity, an effective HIV-1 vaccine will likely require Envs derived from multiple subtypes to generate broadly neutralizing antibodies (bNAbs). Soluble Env mimics, like the native flexibly linked (NFL) and SOSIP trimers, derived from the subtype A BG505 Env, form homogeneous, stable native-like trimers. However, other Env sequences, such as JRFL and 16055 from subtypes B and C, do so to a lesser degree. The high-resolution BG505 SOSIP crystal structures permit the identification and redesign of Env elements involved in trimer stability. Here, we identified structure trimer-derived (TD) residues that increased the propensity of the subtype B JRFL and subtype C 16055 Env sequences to form well-ordered, homogenous, and highly stable soluble trimers. The generation of these spike mimics no longer required antibody-based selection, positive or negative. Using the redesigned subtype B and C trimer representatives as respective foundations, we further stabilized the NFL TD trimers by engineering an intraprotomer disulfide linkage in the prebridging sheet, I201C-A433C (CC), that locks the gp120 in the receptor nontriggered state. We demonstrated that this disulfide pair prevented CD4 induced-conformational rearrangements in NFL trimers derived from the prototypic subtype A, B, and C representatives. Coupling the TD-based design with the engineered disulfide linkage, CC, increased the propensity of Env to form soluble highly stable spike mimics that are resistant to CD4-induced changes. These advances will allow testing of the hypothesis that such stabilized immunogens will more efficiently elicit neutralizing antibodies in small-animal models and primates. IMPORTANCE: HIV-1 displays unprecedented global diversity circulating in the human population. Since the envelope glycoprotein (Env) is the target of neutralizing antibodies, Env-based vaccine candidates that address such diversity are needed. Soluble well-ordered Env mimics, typified by NFL and SOSIP trimers, are attractive vaccine candidates. However, the current designs do not allow most Envs to form well-ordered trimers. Here, we made design modifications to increase the propensity of representatives from two of the major HIV subtypes to form highly stable trimers. This approach should be applicable to other viral Envs, permitting the generation of a repertoire of homogeneous, highly stable trimers. The availability of such an array will allow us to assess if sequential or cocktail immune strategies can overcome some of the vaccine challenges presented by HIV diversity.


Assuntos
Antígenos HIV/química , Antígenos HIV/metabolismo , HIV-1/química , Multimerização Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Dissulfetos/metabolismo , Antígenos HIV/genética , HIV-1/genética , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
20.
Am J Kidney Dis ; 66(1): 55-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25600490

RESUMO

BACKGROUND: Pregnancy in kidney disease is considered high risk, but the degree of this risk is unclear. We tested the hypothesis that kidney disease in pregnancy is associated with adverse maternal and fetal outcomes. STUDY DESIGN: Retrospective study comparing pregnant women with and without kidney disease. SETTING & PARTICIPANTS: Using data from an integrated health care delivery system from 2000 through 2013, a total of 778 women met the criteria for kidney disease. Using a pool of 74,105 women without kidney disease, we selected 778 women to use for matches for the women with kidney disease. These women were matched 1:1 by age, race, and history of diabetes, chronic hypertension, liver disease, and connective tissue disease. PREDICTOR: Kidney disease was defined using the NKF-KDOQI definition for chronic kidney disease or International Classification of Diseases, Ninth Revision codes prior to pregnancy or serum creatinine level > 1.2mg/dL and/or proteinuria in the first trimester. OUTCOMES & MEASUREMENTS: Maternal outcomes included preterm delivery, delivery by cesarean section, preeclampsia/eclampsia, length of stay at hospital (>3 days), and maternal death. Fetal outcomes included low birth weight (weight < 2,500g), small for gestational age, number of admissions to neonatal intensive care unit, and infant death. RESULTS: Compared with women without kidney disease, those with kidney disease had 52% increased odds of preterm delivery (OR, 1.52; 95% CI, 1.16-1.99) and 33% increased odds of delivery by cesarean section (OR, 1.33; 95% CI, 1.06-1.66). Infants born to women with kidney disease had 71% increased odds of admission to the neonatal intensive care unit or infant death compared with infants born to women without kidney disease (OR, 1.71; 95% CI, 1.17-2.51). Kidney disease also was associated with 2-fold increased odds of low birth weight (OR, 2.38; 95% CI, 1.64-3.44). Kidney disease was not associated with increased risk of maternal death. LIMITATIONS: Data for level of kidney function and cause of death not available. CONCLUSIONS: Kidney disease in pregnancy is associated independently with adverse maternal and fetal outcomes when other comorbid conditions are controlled by matching.


Assuntos
Nefropatias/epidemiologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Adulto , Causas de Morte , Cesárea/estatística & dados numéricos , Comorbidade , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Nefropatias/fisiopatologia , Tempo de Internação/estatística & dados numéricos , Mortalidade Materna , Trabalho de Parto Prematuro/epidemiologia , Pré-Eclâmpsia/epidemiologia , Gravidez , Complicações na Gravidez/fisiopatologia , Estudos Retrospectivos , Estados Unidos/epidemiologia , Adulto Jovem
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