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1.
Cell ; 184(22): 5527-5540.e18, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34644527

RESUMO

To secure phosphorus (P) from soil, most land plants use a direct phosphate uptake pathway via root hairs and epidermis and an indirect phosphate uptake pathway via mycorrhizal symbiosis. The interaction between these two pathways is unclear. Here, we mapped a network between transcription factors and mycorrhizal symbiosis-related genes using Y1H. Intriguingly, this gene regulatory network is governed by the conserved P-sensing pathway, centered on phosphate starvation response (PHR) transcription factors. PHRs are required for mycorrhizal symbiosis and regulate symbiosis-related genes via the P1BS motif. SPX-domain proteins suppress OsPHR2-mediated induction of symbiosis-related genes and inhibit mycorrhizal infection. In contrast, plants overexpressing OsPHR2 show improved mycorrhizal infection and are partially resistant to P-mediated inhibition of symbiosis. Functional analyses of network nodes revealed co-regulation of hormonal signaling and mycorrhizal symbiosis. This network deciphers extensive regulation of mycorrhizal symbiosis by endogenous and exogenous signals and highlights co-option of the P-sensing pathway for mycorrhizal symbiosis.


Assuntos
Redes Reguladoras de Genes , Micorrizas/genética , Micorrizas/fisiologia , Fosfatos/deficiência , Simbiose/genética , Simbiose/fisiologia , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Mutação/genética , Oryza/genética , Oryza/microbiologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/metabolismo , Técnicas do Sistema de Duplo-Híbrido
2.
J Virol ; 98(3): e0172023, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38412036

RESUMO

The rational design of HIV-1 immunogens to trigger the development of broadly neutralizing antibodies (bNAbs) requires understanding the viral evolutionary pathways influencing this process. An acute HIV-1-infected individual exhibiting >50% plasma neutralization breadth developed neutralizing antibody specificities against the CD4-binding site (CD4bs) and V1V2 regions of Env gp120. Comparison of pseudoviruses derived from early and late autologous env sequences demonstrated the development of >2 log resistance to VRC13 but not to other CD4bs-specific bNAbs. Mapping studies indicated that the V3 and CD4-binding loops of Env gp120 contributed significantly to developing resistance to the autologous neutralizing response and that the CD4-binding loop (CD4BL) specifically was responsible for the developing resistance to VRC13. Tracking viral evolution during the development of this cross-neutralizing CD4bs response identified amino acid substitutions arising at only 4 of 11 known VRC13 contact sites (K282, T283, K421, and V471). However, each of these mutations was external to the V3 and CD4BL regions conferring resistance to VRC13 and was transient in nature. Rather, complete resistance to VRC13 was achieved through the cooperative expression of a cluster of single amino acid changes within and immediately adjacent to the CD4BL, including a T359I substitution, exchange of a potential N-linked glycosylation (PNLG) site to residue S362 from N363, and a P369L substitution. Collectively, our data characterize complex HIV-1 env evolution in an individual developing resistance to a VRC13-like neutralizing antibody response and identify novel VRC13-associated escape mutations that may be important to inducing VRC13-like bNAbs for lineage-based immunogens.IMPORTANCEThe pursuit of eliciting broadly neutralizing antibodies (bNAbs) through vaccination and their use as therapeutics remains a significant focus in the effort to eradicate HIV-1. Key to our understanding of this approach is a more extensive understanding of bNAb contact sites and susceptible escape mutations in HIV-1 envelope (env). We identified a broad neutralizer exhibiting VRC13-like responses, a non-germline restricted class of CD4-binding site antibody distinct from the well-studied VRC01-class. Through longitudinal envelope sequencing and Env-pseudotyped neutralization assays, we characterized a complex escape pathway requiring the cooperative evolution of four amino acid changes to confer complete resistance to VRC13. This suggests that VRC13-class bNAbs may be refractory to rapid escape and attractive for therapeutic applications. Furthermore, the identification of longitudinal viral changes concomitant with the development of neutralization breadth may help identify the viral intermediates needed for the maturation of VRC13-like responses and the design of lineage-based immunogens.


Assuntos
Anticorpos Amplamente Neutralizantes , Infecções por HIV , Humanos , Aminoácidos , Anticorpos Amplamente Neutralizantes/imunologia , Antígenos CD4/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Epitopos , Anticorpos Anti-HIV , Antígenos HIV , Proteína gp120 do Envelope de HIV/genética , Soropositividade para HIV , HIV-1/genética , Vacinas contra a AIDS/imunologia
3.
BMC Bioinformatics ; 25(1): 206, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840038

RESUMO

BACKGROUND: Bisulfite sequencing (BS-Seq) is a fundamental technique for characterizing DNA methylation profiles. Genotype calling from bisulfite-converted BS-Seq data allows allele-specific methylation analysis and the concurrent exploration of genetic and epigenetic profiles. Despite various methods have been proposed, single nucleotide polymorphisms (SNPs) calling from BS-Seq data, particularly for SNPs on chromosome X and in the presence of contaminative data, poses ongoing challenges. RESULTS: We introduce bsgenova, a novel SNP caller tailored for bisulfite sequencing data, employing a Bayesian multinomial model. The performance of bsgenova is assessed by comparing SNPs called from real-world BS-Seq data with those from corresponding whole-genome sequencing (WGS) data across three human cell lines. bsgenova is both sensitive and precise, especially for chromosome X, compared with three existing methods. Moreover, in the presence of low-quality reads, bsgenova outperforms other methods notably. In addition, bsgenova is meticulously implemented, leveraging matrix imputation and multi-process parallelization. Compared to existing methods, bsgenova stands out for its speed and efficiency in memory and disk usage. Furthermore, bsgenova integrates bsextractor, a methylation extractor, enhancing its flexibility and expanding its utility. CONCLUSIONS: We introduce bsgenova for SNP calling from bisulfite-sequencing data. The source code is available at https://github.com/hippo-yf/bsgenova under license GPL-3.0.


Assuntos
Metilação de DNA , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sulfitos , Humanos , Metilação de DNA/genética , Sulfitos/química , Análise de Sequência de DNA/métodos , Genótipo , Software , Sequenciamento Completo do Genoma/métodos , Teorema de Bayes
4.
BMC Genomics ; 25(1): 305, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519892

RESUMO

BACKGROUND: The ageing process is a multifaceted phenomenon marked by the gradual deterioration of cellular and organismal functions, accompanied by an elevated susceptibility to diseases. The intricate interplay between genetic and environmental factors complicates research, particularly in complex mammalian models. In this context, simple invertebrate organisms have been pivotal, but the current models lack detectable DNA methylation limiting the exploration of this critical epigenetic ageing mechanism. This study introduces Nasonia vitripennis, the jewel wasp, as an innovative invertebrate model for investigating the epigenetics of ageing. Leveraging its advantages as a model organism and possessing a functional DNA methylation system, Nasonia emerges as a valuable addition to ageing research. RESULTS: Whole-genome bisulfite sequencing unveiled dynamic alterations in DNA methylation, with differentially methylated CpGs between distinct time points in both male and female wasps. These changes were associated with numerous genes, enriching for functions related to telomere maintenance, histone methylation, and mRNA catabolic processes. Additionally, other CpGs were found to be variably methylated at each timepoint. Sex-specific effects on epigenetic entropy were observed, indicating differential patterns in the loss of epigenetic stability over time. Constructing an epigenetic clock containing 19 CpGs revealed a robust correlation between epigenetic age and chronological age. CONCLUSIONS: Nasonia vitripennis emerges as a promising model for investigating the epigenetics of ageing, shedding light on the intricate dynamics of DNA methylation and their implications for age-related processes. This research not only expands the repertoire of ageing models but also opens avenues for deeper exploration of epigenetic mechanisms in the context of ageing.


Assuntos
Epigenoma , Vespas , Animais , Feminino , Masculino , Vespas/genética , Epigênese Genética , Metilação de DNA , Mamíferos/genética
5.
BMC Genomics ; 25(1): 711, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044136

RESUMO

BACKGROUND: Bacterial spot of pepper (BSP), caused by four different Xanthomonas species, primarily X. euvesicatoria (Xe), poses a significant challenge in pepper cultivation. Host resistance is considered the most important approach for BSP control, offering long-term protection and sustainability. While breeding for resistance to BSP for many years focused on dominant R genes, introgression of recessive resistance has been a more recent focus of breeding programs. The molecular interactions underlying recessive resistance remain poorly understood. RESULTS: In this study, transcriptomic analyses were performed to elucidate defense responses triggered by Xe race P6 infection by two distinct pepper lines: the Xe-resistant line ECW50R containing bs5, a recessive resistance gene that confers resistance to all pepper Xe races, and the Xe-susceptible line ECW. The results revealed a total of 3357 upregulated and 4091 downregulated genes at 0, 1, 2, and 4 days post-inoculation (dpi), with the highest number of differentially expressed genes (DEGs) observed at 2 dpi. Pathway analysis highlighted DEGs in key pathways such as plant-pathogen interaction, MAPK signaling pathway, plant hormone signal transduction, and photosynthesis - antenna proteins, along with cysteine and methionine metabolism. Notably, upregulation of genes associated with PAMP-Triggered Immunity (PTI) was observed, including components like FLS2, Ca-dependent pathways, Rboh, and reactive oxygen species (ROS) generation. In support of these results, infiltration of ECW50R leaves with bacterial suspension of Xe led to observable hydrogen peroxide accumulation without a rapid increase in electrolyte leakage, suggestive of the absence of Effector-Triggered Immunity (ETI). Furthermore, the study confirmed that bs5 does not disrupt the effector delivery system, as evidenced by incompatible interactions between avirulence genes and their corresponding dominant resistant genes in the bs5 background. CONCLUSION: Overall, these findings provide insights into the molecular mechanisms underlying bs5-mediated resistance in pepper against Xe and suggest a robust defense mechanism in ECW50R, primarily mediated through PTI. Given that bs5 provides early strong response for resistance, combining this resistance with other dominant resistance genes will enhance the durability of resistance to BSP.


Assuntos
Capsicum , Resistência à Doença , Perfilação da Expressão Gênica , Doenças das Plantas , Xanthomonas , Capsicum/genética , Capsicum/microbiologia , Capsicum/imunologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Transcriptoma
6.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34874989

RESUMO

Investigating differentially methylated regions (DMRs) presented in different tissues or cell types can help to reveal the mechanisms behind the tissue-specific gene expression. The identified tissue-/disease-specific DMRs also can be used as feature markers for spotting the tissues-of-origins of cell-free DNA (cfDNA) in noninvasive diagnosis. In recent years, many methods have been proposed to detect DMRs. However, due to the lack of benchmark DMRs, it is difficult for researchers to choose proper methods and select desirable DMR sets for downstream studies. The application of DMRs, used as feature markers, can be benefited by the longer length of DMRs containing more CpG sites when a threshold is given for the methylation differences of DMRs. According to this, two metrics ($Qn$ and $Ql$), in which the CpG numbers and lengths of DMRs with different methylation differences are weighted differently, are proposed in this paper to evaluate the DMR sets predicted by different methods on BS-seq data. DMR sets predicted by eight methods on both simulated datasets and real BS-seq datasets are evaluated by the proposed metrics, the benchmark-based metrics, and the enrichment analysis of biological data, including genomic features, transcription factors and histones. The rank correlation analysis shows that the $Qn$ and $Ql$ are highly correlated to the benchmark metrics for simulated datasets and the biological data enrichment analysis for real BS-seq data. Therefore, with no need for additional biological data, the proposed metrics can help researchers selecting a more suitable DMR set on a certain BS-seq dataset.


Assuntos
Benchmarking , Metilação de DNA , Ilhas de CpG , Genoma , Genômica , Análise de Sequência de DNA
7.
New Phytol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803107

RESUMO

Phosphate starvation response (PHR) transcription factors play essential roles in regulating phosphate uptake in plants through binding to the P1BS cis-element in the promoter of phosphate starvation response genes. Recently, PHRs were also shown to positively regulate arbuscular mycorrhizal colonization in rice and lotus by controlling the expression of many symbiotic genes. However, their role in arbuscule development has remained unclear. In Medicago, we previously showed that arbuscule degradation is controlled by two SPX proteins that are highly expressed in arbuscule-containing cells. Since SPX proteins bind to PHRs and repress their activity in a phosphate-dependent manner, we investigated whether arbuscule maintenance is also regulated by PHR. Here, we show that PHR2 is a major regulator of the phosphate starvation response in Medicago. Knockout of phr2 showed reduced phosphate starvation response, symbiotic gene expression, and fungal colonization levels. However, the arbuscules that formed showed less degradation, suggesting a negative role for PHR2 in arbuscule maintenance. This was supported by the observation that overexpression of PHR2 led to enhanced degradation of arbuscules. Although many arbuscule-induced genes contain P1BS elements in their promoters, we found that the P1BS cis-elements in the promoter of the symbiotic phosphate transporter PT4 are not required for arbuscule-containing cell expression. Since both PHR2 and SPX1/3 negatively affect arbuscule maintenance, our results indicate that they control arbuscule maintenance partly via different mechanisms. While PHR2 potentiates symbiotic gene expression and colonization, its activity in arbuscule-containing cells needs to be tightly controlled to maintain a successful symbiosis in Medicago.

8.
Insect Mol Biol ; 33(5): 481-492, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38348493

RESUMO

Epigenetic mechanisms, such as DNA methylation, are crucial factors in animal development. In some mammals, almost all DNA methylation is erased during embryo development and re-established in a sex- and cell-specific manner. This erasure and re-establishment is thought to primarily be a vertebrate-specific trait. Insects are particularly interesting in terms of development as many species often undergo remarkable morphological changes en route to maturity, that is, morphogenesis. However, little is known about the role of epigenetic mechanisms in this process across species. We have used whole-genome bisulfite sequencing to track genome-wide DNA methylation changes through the development of an economically and environmentally important pollinator species, the bumblebee Bombus terrestris (Hymenoptera:Apidae Linnaeus). We find overall levels of DNA methylation vary throughout development, and we find developmentally relevant differentially methylated genes throughout. Intriguingly, we have identified a depletion of DNA methylation in ovaries/eggs and an enrichment of highly methylated genes in sperm. We suggest this could represent a sex-specific DNA methylation erasure event. To our knowledge, this is the first suggestion of possible developmental DNA methylation erasure in an insect species. This study lays the required groundwork for functional experimental work to determine if there is a causal nature to the DNA methylation differences identified. Additionally, the application of single-cell methylation sequencing to this system will enable more accurate identification of if or when DNA methylation is erased during development.


Assuntos
Metilação de DNA , Animais , Abelhas/genética , Abelhas/crescimento & desenvolvimento , Feminino , Masculino , Epigênese Genética , Morfogênese/genética
9.
Virol J ; 21(1): 154, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978059

RESUMO

BACKGROUND: Rabies is a fatal zoonotic disease whose pathogenesis has not been fully elucidated, and vaccination is the only effective method for protecting against rabies virus infection. Most inactivated vaccines are produced using Vero cells, which are African green monkey kidney cells, to achieve large-scale production. However, there is a potential carcinogenic risk due to nonhuman DNA contamination. Thus, replacing Vero cells with human diploid cells may be a safer strategy. In this study, we developed a novel 2BS cell-adapted rabies virus strain and analysed its sequence, virulence and immunogenicity to determine its application potential as a human diploid cell inactivated vaccine. METHODS AND RESULTS: The 2BS cell-adapted rabies virus strain 2aG4-B40 was established by passage for 40 generations and selection of plaques in 2BS cells. RNA sequence analysis revealed that mutations in 2BS cell-adapted strains were not located at key sites that regulate the production of neutralizing antibodies or virulence in the aG strain (GQ412744.1). The gradual increase in virulence (remaining above 7.0 logLD50/ml from the 40th to 55th generation) and antigen further indicated that these mutations may increase the affinity of the adapted strains for human diploid cells. Identification tests revealed that the 2BS cell-adapted virus strain was neutralized by anti-rabies serum, with a neutralization index of 19,952. PrEP and PEP vaccination and the NIH test further indicated that the vaccine prepared with the 2aG4-B40 strain had high neutralizing antibody levels (2.24 to 46.67 IU/ml), immunogenicity (protection index 270) and potency (average 11.6 IU/ml). CONCLUSIONS: In this study, a 2BS cell-adapted strain of the 2aG4 rabies virus was obtained by passage for 40 generations. The results of sequencing analysis and titre determination of the adapted strain showed that the mutations in the adaptive process are not located at key sequence regions of the virus, and these mutations may enhance the affinity of the adapted strain for human diploid cells. Moreover, vaccines made from the adapted strain 2aG4-B40 had high potency and immunogenicity and could be an ideal candidate rabies virus strain for inactivated vaccine preparation.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina Antirrábica , Vírus da Raiva , Raiva , Vírus da Raiva/imunologia , Vírus da Raiva/genética , Vírus da Raiva/patogenicidade , Animais , Vacina Antirrábica/imunologia , Vacina Antirrábica/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Raiva/prevenção & controle , Raiva/imunologia , Raiva/virologia , Humanos , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Virulência , Vacinas de Produtos Inativados/imunologia , Células Vero , China , Camundongos , Linhagem Celular , Mutação , Feminino , Imunogenicidade da Vacina
10.
Mol Biol Rep ; 51(1): 311, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372841

RESUMO

Drought is an enormous threat to global crop production. In order to ensure food security for the burgeoning population, we must develop drought tolerant crop varieties. This necessitates the identification of drought-responsive genes and understanding the mechanisms involved in their regulation. DNA methylation is a widely studied mechanism of epigenetic regulation of gene expression, which is known to play vital role in conferring tolerance to various biotic and abiotic stress factors. The recent advances in next-generation sequencing (NGS) technologies, has allowed unprecedented access to genome-wide methylation marks, with single base resolution. The most important roles of DNA methylation have been studied in terms of gene body methylation (gbM), which is associated with regulation of both transcript abundance and its stability. The availability of mutants for the various genes encoding enzymes involved in methylation of DNA has allowed ascertainment of the biological significance of methylation. Even though a vast number of reports have emerged in the recent past, where both genome-wide methylation landscape and locus specific changes in DNA methylation have been studied, a conclusive picture with regards to the biological role of DNA methylation is still lacking. Compounding this, is the lack of sufficient evidence supporting the heritability of these epigenetic changes. Amongst the various epigenetic variations, the DNA methylation changes are observed to be the most stable. This review describes the drought-induced changes in DNA methylation identified across different plant species. We also briefly describe the stress memory contributed by these changes. The identification of heritable, drought-induced methylation marks would broaden the scope of crop improvement in the future.


Assuntos
Metilação de DNA , Epigênese Genética , Metilação de DNA/genética , Secas , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala
11.
Sensors (Basel) ; 24(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38793909

RESUMO

Constipation is a common gastrointestinal disorder that impairs quality of life. Evaluating bowel motility via traditional methods, such as MRI and radiography, is expensive and inconvenient. Bowel sound (BS) analysis has been proposed as an alternative, with BS-time-domain acoustic features (BSTDAFs) being effective for evaluating bowel motility via several food and drink consumption tests. However, the effect of BSTDAFs before drink consumption on those after drink consumption is yet to be investigated. This study used BS-based stimulus-response plots (BSSRPs) to investigate this effect on 20 participants who underwent drinking tests. A strong negative correlation was observed between the number of BSs per minute before carbonated water consumption and the ratio of that before and after carbonated water consumption. However, a similar trend was not observed when the participants drank cold water. These findings suggest that when carbonated water is drunk, bowel motility before ingestion affects motor response to ingestion. This study provides a non-invasive BS-based approach for evaluating motor response to food and drink, offering a new research window for investigators in this field.


Assuntos
Ingestão de Líquidos , Motilidade Gastrointestinal , Humanos , Ingestão de Líquidos/fisiologia , Masculino , Motilidade Gastrointestinal/fisiologia , Feminino , Adulto , Adulto Jovem , Constipação Intestinal/fisiopatologia , Voluntários Saudáveis , Água Carbonatada
12.
Sensors (Basel) ; 24(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38931583

RESUMO

In base-station-based underwater wireless acoustic networks (B-UWANs), effective handover mechanisms are necessary to ensure seamless data services for mobile nodes such as autonomous underwater vehicles (AUVs). Unlike terrestrial base stations (BSs), moored buoy BSs in B-UWANs experience motion responses due to wave loads under environmental conditions, posing unique challenges to the handover process. This study examines how BS motion affects handover decision errors, which arise when AUVs incorrectly initiate handovers to unintended BSs due to BS motion. By utilizing the AUV-BS distance as a handover triggering parameter, our analysis reveals a significant increase in decision errors within the overlapping regions when both the current and target BSs are in motion, especially when moving in the same direction. In addition, these errors intensify with the magnitude of BS motion and are exacerbated by smaller BS network radii. Based on these simulation results, we present an analytical framework that not only measures the influence of BS motion on the AUV-BS distance but also provides strategic insights for refining underwater handover protocols, thereby enhancing operational reliability and service continuity in B-UWANs.

13.
Radiol Med ; 129(8): 1224-1240, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39080226

RESUMO

Osteoporosis is the most prevalent skeletal disorder, a condition that is associated with significant social and healthcare burden. In the elderly, osteoporosis is commonly associated with sarcopenia, further increasing the risk of fracture. Several imaging techniques are available for a non-invasive evaluation of osteoporosis and sarcopenia. This review focuses on dual-energy X-ray absorptiometry (DXA), as this technique offers the possibility to evaluate bone mineral density and body composition parameters with good precision and accuracy. DXA is also able to evaluate the amount of aortic calcification for cardiovascular risk estimation. Additionally, new DXA-based parameters have been developed in recent years to further refine fracture risk estimation, such as the Trabecular Bone Score and the Bone Strain Index. Finally, we describe the recent advances of a newly developed ultrasound-based technology known as Radiofrequency Echographic Multi-Spectrometry, which represent the latest non-ionizing approach for osteoporosis evaluation at central sites.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Osteoporose , Humanos , Absorciometria de Fóton/métodos , Osteoporose/diagnóstico por imagem , Sarcopenia/diagnóstico por imagem , Composição Corporal , Ultrassonografia/métodos , Medição de Risco
14.
Nano Lett ; 23(5): 1673-1679, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36849129

RESUMO

Boron-based two-dimensional (2D) materials are an excellent platform for nanoelectronics applications. Rhombohedral boron monosulfide (r-BS) is attracting particular attention because of its unique layered crystal structure suitable for exploring various functional properties originating in the 2D nature. However, studies to elucidate its fundamental electronic states have been largely limited because only tiny powdered crystals were available, hindering a precise investigation by spectroscopy such as angle-resolved photoemission spectroscopy (ARPES). Here we report the direct mapping of the band structure with a tiny (∼20 × 20 µm2) r-BS powder crystal by utilizing microfocused ARPES. We found that r-BS is a p-type semiconductor with a band gap of >0.5 eV characterized by the anisotropic in-plane effective mass. The present results demonstrate the high applicability of micro-ARPES to tiny powder crystals and widen an opportunity to access the yet-unexplored electronic states of various novel materials.

15.
J Bacteriol ; 205(9): e0014023, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37676009

RESUMO

Although ribosomes are generally examined in aggregate, ribosomes can be heterogenous in composition. Evidence is accumulating that changes in ribosome composition may result in altered function, such that ribosome heterogeneity may provide a mechanism to regulate protein synthesis. Ribosome heterogeneity in the human pathogen Francisella tularensis results from incorporation of one of three homologs of bS21, a small ribosomal subunit protein demonstrated to regulate protein synthesis in other bacteria. Loss of one homolog, bS21-2, results in genome-wide post-transcriptional changes in protein abundance. This suggests that bS21-2 can, either directly or indirectly, lead to preferential translation of particular mRNAs. Here, we examine the potential of bS21-2 to function in a leader sequence-dependent manner and to function indirectly, via Hfq. We found that the 5´ untranslated region (UTR) of some bS21-2-responsive genes, including key virulence genes, is sufficient to alter translation in cells lacking bS21-2. We further identify features of a 5´ UTR that allow responsiveness to bS21-2. These include an imperfect Shine-Dalgarno sequence and a particular six nucleotide sequence. Our results are consistent with a model in which a bS21 homolog increases the efficiency of translation initiation through interactions with specific leader sequences. With respect to bS21-2 indirectly regulating translation via the RNA-binding protein Hfq, we found that Hfq controls transcript abundance rather than protein synthesis, impacting virulence gene expression via a distinct mechanism. Together, we determined that ribosome composition in F. tularensis regulates translation in a leader sequence-dependent manner, a regulatory mechanism which may be used in other bacteria. IMPORTANCE Ribosome heterogeneity is common in bacteria, and there is mounting evidence that ribosome composition plays a regulatory role in protein synthesis. However, mechanisms of ribosome-driven gene regulation are not well understood. In the human pathogen Francisella tularensis, which encodes multiple homologs for the ribosomal protein bS21, loss of one homolog impacts protein synthesis and virulence. Here, we explore the mechanism behind bS21-mediated changes in protein synthesis, finding that they can be linked to altered translation initiation and are dependent on specific sequences in the leaders of transcripts. Our data support a model in which ribosome composition regulates gene expression through translation, a strategy that may be conserved in diverse organisms with various sources of ribosome heterogeneity.


Assuntos
Francisella tularensis , Humanos , Francisella tularensis/genética , Ribossomos/genética , Proteínas Ribossômicas/genética , Regiões 5' não Traduzidas , RNA Mensageiro/genética
16.
BMC Bioinformatics ; 24(1): 33, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721080

RESUMO

BACKGROUND: Whole genome bisulfite sequencing (WGBS), possesses the aptitude to dissect methylation status at the nucleotide-level resolution of 5-methylcytosine (5-mC) on a genome-wide scale. It is a powerful technique for epigenome in various cell types, and tissues. As a recently established next-generation sequencing (NGS) platform, GenoLab M is a promising alternative platform. However, its comprehensive evaluation for WGBS has not been reported. We sequenced two bisulfite-converted mammal DNA in this research using our GenoLab M and NovaSeq 6000, respectively. Then, we systematically compared those data via four widely used WGBS tools (BSMAP, Bismark, BatMeth2, BS-Seeker2) and a new bisulfite-seq tool (BSBolt). We interrogated their computational time, genome depth and coverage, and evaluated their percentage of methylated Cs. RESULT: Here, benchmarking a combination of pre- and post-processing methods, we found that trimming improved the performance of mapping efficiency in eight datasets. The data from two platforms uncovered ~ 80% of CpG sites genome-wide in the human cell line. Those data sequenced by GenoLab M achieved a far lower proportion of duplicates (~ 5.5%). Among pipelines, BSMAP provided an intriguing representation of 5-mC distribution at CpG sites with 5-mC levels > ~ 78% in datasets from human cell lines, especially in the GenoLab M. BSMAP performed more advantages in running time, uniquely mapped reads percentages, genomic coverage, and quantitative accuracy. Finally, compared with the previous methylation pattern of human cell line and mouse tissue, we confirmed that the data from GenoLab M performed similar consistency and accuracy in methylation levels of CpG sites with that from NovaSeq 6000. CONCLUSION: Together we confirmed that GenoLab M was a qualified NGS platform for WGBS with high performance. Our results showed that BSMAP was the suitable pipeline that allowed for WGBS studies on the GenoLab M platform.


Assuntos
Benchmarking , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Animais , Camundongos , Sequenciamento Completo do Genoma , Mamíferos/genética
17.
Neuroimage ; 277: 120251, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37364741

RESUMO

Fulfilling potentials of ultrahigh field for pseudo-Continuous Arterial Spin Labeling (pCASL) has been hampered by B1/B0 inhomogeneities that affect pCASL labeling, background suppression (BS), and the readout sequence. This study aimed to present a whole-cerebrum distortion-free three-dimensional (3D) pCASL sequence at 7T by optimizing pCASL labeling parameters, BS pulses, and an accelerated Turbo-FLASH (TFL) readout. A new set of pCASL labeling parameters (Gave = 0.4 mT/m, Gratio = 14.67) was proposed to avoid interferences in bottom slices while achieving robust labeling efficiency (LE). An OPTIM BS pulse was designed based on the range of B1/B0 inhomogeneities at 7T. A 3D TFL readout with 2D-CAIPIRINHA undersampling (R = 2 × 2) and centric ordering was developed, and the number of segments (Nseg) and flip angle (FA) were varied in simulation to achieve the optimal trade-off between SNR and spatial blurring. In-vivo experiments were performed on 19 subjects. The results showed that the new set of labeling parameters effectively achieved whole-cerebrum coverage by eliminating interferences in bottom slices while maintaining a high LE. The OPTIM BS pulse achieved 33.3% higher perfusion signal in gray matter (GM) than the original BS pulse with a cost of 4.8-fold SAR. Incorporating a moderate FA (8°) and Nseg (2), whole-cerebrum 3D TFL-pCASL imaging was achieved with a 2 × 2 × 4 mm3 resolution without distortion and susceptibility artifacts compared to 3D GRASE-pCASL. In addition, 3D TFL-pCASL showed a good to excellent test-retest repeatability and potential of higher resolution (2 mm isotropic). The proposed technique also significantly improved SNR when compared to the same sequence at 3T and simultaneous multislice TFL-pCASL at 7T. By combining a new set of labeling parameters, OPTIM BS pulse, and accelerated 3D TFL readout, we achieved high resolution pCASL at 7T with whole-cerebrum coverage, detailed perfusion and anatomical information without distortion, and sufficient SNR.


Assuntos
Encéfalo , Imageamento Tridimensional , Humanos , Imageamento Tridimensional/métodos , Encéfalo/diagnóstico por imagem , Marcadores de Spin , Artérias , Angiografia por Ressonância Magnética/métodos , Circulação Cerebrovascular , Córtex Cerebral
18.
Am J Physiol Renal Physiol ; 325(6): F779-F791, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823199

RESUMO

Patients with urinary tract infections (UTIs) suffer from urinary frequency, urgency, dysuria, and suprapubic pain, but the mechanisms by which bladder afferents sense the presence of uropathogens and encode this information is not well understood. Calcitonin gene-related peptide (CGRP) is a 37-mer neuropeptide found in a subset of bladder afferents that terminate primarily in the lamina propria. Here, we report that the CGRP receptor antagonist BIBN4096BS lessens lower urinary tract symptoms and prevents the development of pelvic allodynia in mice inoculated with uropathogenic Escherichia coli (UPEC) without altering urine bacterial loads or the host immune response to the infection. These findings indicate that CGRP facilitates the processing of noxious/inflammatory stimuli during UPEC infection. Using fluorescent in situ hybridization, we identified a population of suburothelial fibroblasts in the lamina propria, a region where afferent fibers containing CGRP terminate, that expresses the canonical CGRP receptor components Calcrl and Ramp1. We propose that these fibroblasts, in conjunction with CGRP+ afferents, form a circuit that senses substances released during the infection and transmit this noxious information to the central nervous system.NEW & NOTEWORTHY Afferent C fibers release neuropeptides including calcitonin gene-related peptide (CGRP). Here, we show that the specific CGRP receptor antagonist, BIBN409BS, ameliorates lower urinary tract symptoms and pelvic allodynia in mice inoculated with uropathogenic E. coli. Using fluorescent in situ hybridization, we identified a population of suburothelial fibroblasts in the lamina propria that expresses the canonical CGRP receptor. Our findings indicate that CGRP contributes to the transmission of nociceptive information arising from the bladder.


Assuntos
Cistite , Sintomas do Trato Urinário Inferior , Camundongos , Humanos , Animais , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/fisiologia , Peptídeo Relacionado com Gene de Calcitonina , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/farmacologia , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/uso terapêutico , Hiperalgesia , Escherichia coli , Hibridização in Situ Fluorescente
19.
Clin Immunol ; 255: 109743, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37604356

RESUMO

OBJECTIVE: Blau syndrome (BS), considered a rare pediatric autoinflammatory disease, is characterised by a triad of granulomatous arthritis, dermatitis and uveitis. Here we present a tale of three families visited in our outpatient department in the last two years (2020-2022) where more than one member was affected with either skin, ophthalmological and joint involvement with either biopsy-proven granuloma or genetic mutation at NOD2 gene suggesting the diagnosis of BS. CASE SERIES: The first family had three affected members where the mother and her two children had skin changes, polyarthritis and a pathogenic mutation in NOD2 gene (exon 4, c.1000C > T, p.Arg334Trp) suggesting BS. The second family had two affected members where both mother and her son had uveitis, skin changes with NOD2 mutation at exon 4 with c.1147G > A (p Glu 383 Lys) variant. The son also had polyarthritis and his skin biopsy was suggestive of granulomatous inflammation. In the third family with two affected members, we found a mutation in NOD2 on exon 4 (c 1324C > T, p.Lys 442 Phe) which was described as pathogenic with only one report published till date. CONCLUSION: These three cases presented to us within the last two years and led to a diagnosis of BS in three other family members with discrete mutations (commonest to rarest) on the NOD2 gene in the three families.


Assuntos
Artrite , Sarcoidose , Uveíte , Criança , Feminino , Humanos , Artrite/genética , Índia , Mães , Mutação , Proteína Adaptadora de Sinalização NOD2/genética , Sarcoidose/genética , Uveíte/genética , Uveíte/diagnóstico , Masculino
20.
Eur J Nutr ; 62(6): 2687-2703, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37273002

RESUMO

PURPOSE: When blended, animal and plant proteins can complement each other in terms of amino acid composition and release time. In this study, we investigated whether the blended protein diet has a better feeding effect than the single protein diet, and to reveal the differences in growth and intestinal microbiota composition caused by the blended protein diet. METHODS: Forty Sprague Dawley (SD) rats received diets with different protein sources, including casein (C), whey protein (WP), black soybean protein (BSP), and black soybean-whey blended protein (BS-WP), for eight weeks. To investigate the effects of blended protein supplement on gut microbiota and metabolites, we performed a high throughput 16S rDNA sequencing and fecal metabolomics profiling. In addition, we determined growth and serum biochemical indices, and conducted intestinal morphology analyses. RESULTS: Compared to those in the BSP and WP groups, the daily body weight gain and feed conversion efficiency increased in the BS-WP group. Serum biochemical indices indicated that the protein utilization efficiency of the WP and BS-WP groups was relatively high, and the BS-WP blended protein diet improved the protein adoption rate. The BS-WP blended protein diet also improved intestinal tissue morphology and promoted intestinal villi development compared to the single protein diets. Furthermore, dietary protein altered the composition of gut microbiota, the gut microbial diversity of rats fed with the BS-WP diet was significantly (P < 0.05) higher than that of the other groups. The difference in dietary protein corresponded with an alteration of fecal amino acids and their metabolites, and tryptophan and tyrosine metabolism were the key mechanisms leading to the changes in fecal microbial composition. CONCLUSION: Dietary protein sources played an important role in the growth and development of rats by influencing intestinal metabolism and microbial composition. The BS-WP blended protein diet was more conducive to nutrient absorption than the single protein diet. Furthermore, blended protein increased the diversity of intestinal microbes and aided the establishment of intestinal barrier function.


Assuntos
Microbioma Gastrointestinal , Ratos , Animais , Ratos Sprague-Dawley , Dieta , Proteínas do Soro do Leite/farmacologia , Caseínas/farmacologia , Proteínas Alimentares/farmacologia , Metabolômica , Ração Animal
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