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1.
Trends Genet ; 39(9): 649-671, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37230864

RESUMO

Long-read sequencing (LRS) technologies have provided extremely powerful tools to explore genomes. While in the early years these methods suffered technical limitations, they have recently made significant progress in terms of read length, throughput, and accuracy and bioinformatics tools have strongly improved. Here, we aim to review the current status of LRS technologies, the development of novel methods, and the impact on genomics research. We will explore the most impactful recent findings made possible by these technologies focusing on high-resolution sequencing of genomes and transcriptomes and the direct detection of DNA and RNA modifications. We will also discuss how LRS methods promise a more comprehensive understanding of human genetic variation, transcriptomics, and epigenetics for the coming years.


Assuntos
Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Genômica/métodos , Análise de Sequência de DNA/métodos , Biologia Computacional , Perfilação da Expressão Gênica/métodos
2.
Mol Microbiol ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567765

RESUMO

Organization of archaeal chromatin combines bacterial, eukaryotic, and unique characteristics. Many archaeal lineages harbor a wide diversity of small and highly expressed nucleoid-associated proteins, which are involved in DNA structuring. In Sulfolobales, representing model organisms within the Crenarchaeota, Sul7d, Cren7, Sul10a, and Sul12a are well-characterized nucleoid-associated proteins. Here, we combine evidence that the Lrs14 family of DNA binders is part of the repertoire of nucleoid-associated proteins in Sulfolobales. Lrs14-encoding genes are widespread within genomes of different members of the Sulfolobales, typically encoded as four to nine homologs per genome. The Lrs14 proteins harbor a winged helix-turn-helix DNA-binding domain and are typified by a coiled-coil dimerization. They are characterized by distinct sequence- and structure-based features, including redox-sensitive motifs and residues targeted for posttranslational modification, allowing a further classification of the family into five conserved clusters. Lrs14-like proteins have unique DNA-organizing properties. By binding to the DNA nonsequence specifically and in a highly cooperative manner, with a slight preference for AT-rich promoter regions, they introduce DNA kinks and are able to affect transcription of adjacent transcription units either positively or negatively. Genes encoding Lrs14-type proteins display considerable differential expression themselves in response to various stress conditions, with certain homologs being specific to a particular stressor. Taken together, we postulate that members of the Lrs14 family can be considered nucleoid-associated proteins in Sulfolobales, combining a DNA-structuring role with a global gene expression role in response to stress conditions.

3.
BMC Genomics ; 25(1): 292, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504154

RESUMO

BACKGROUND: Dystrophinopathies are the most common X-linked inherited muscle diseases, and the disease-causing gene is DMD. Exonic duplications are a common type of pathogenic variants in the DMD gene, however, 5' end exonic duplications containing exon 1 are less common. When assessing the pathogenicity of exonic duplications in the DMD gene, consideration must be given to their impact on the reading frame. Traditional molecular methods, such as multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS), are commonly used in clinics. However, they cannot discriminate the precise physical locations of breakpoints and structural features of genomic rearrangement. Long-read sequencing (LRS) can effectively overcome this limitation. RESULTS: We used LRS technology to perform whole genome sequencing on three families and analyze the structural variations of the DMD gene, which involves the duplications of exon 1 and/or exon 2. Two distinct variant types encompassing exon 1 in the DMD Dp427m isoform and/or Dp427c isoform are identified, which have been infrequently reported previously. In pedigree 1, the male individuals harboring duplication variant of consecutive exons 1-2 in the DMD canonical transcript (Dp427m) and exon 1 in the Dp427c transcript are normal, indicating the variant is likely benign. In pedigree 3, the patient carries complex SVs involving exon 1 of the DMD Dp427c transcript showing an obvious phenotype. The locations of the breakpoints and the characteristics of structural variants (SVs) are identified by LRS, enabling the classification of the variants' pathogenicity. CONCLUSIONS: Our research sheds light on the complexity of DMD variants encompassing Dp427c/Dp427m promoter regions and emphasizes the importance of cautious interpretation when assessing the pathogenicity of DMD 5' end exonic duplications, particularly in carrier screening scenarios without an affected proband.


Assuntos
Distrofia Muscular de Duchenne , Humanos , Masculino , Distrofina/genética , Éxons , Genômica , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/diagnóstico , Isoformas de Proteínas/genética
4.
Muscle Nerve ; 69(6): 708-718, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558464

RESUMO

INTRODUCTION/AIMS: GNE myopathy is a rare autosomal recessive disorder caused by pathogenic variants in the GNE gene, which is essential for the sialic acid biosynthesis pathway. Although over 300 GNE variants have been reported, some patients remain undiagnosed with monoallelic pathogenic variants. This study aims to analyze the entire GNE genomic region to identify novel pathogenic variants. METHODS: Patients with clinically compatible GNE myopathy and monoallelic pathogenic variants in the GNE gene were enrolled. The other GNE pathogenic variant was verified using comprehensive methods including exon 2 quantitative polymerase chain reaction and nanopore long-read single-molecule sequencing (LRS). RESULTS: A deep intronic GNE variant, c.862+870C>T, was identified in nine patients from eight unrelated families. This variant generates a cryptic splice site, resulting in the activation of a novel pseudoexon between exons 5 and 6. It results in the insertion of an extra 146 nucleotides into the messengerRNA (mRNA), which is predicted to result in a truncated humanGNE1(hGNE1) protein. Peanut agglutinin(PNA) lectin staining of muscle tissues showed reduced sialylation of mucin O-glycans on sarcolemmal glycoproteins. Notably, a third of patients with the c.862+870C>T variant exhibited thrombocytopenia. A common core haplotype harboring the deep intronic GNE variant was found in all these patients. DISCUSSION: The transcript with pseudoexon activation potentially affects sialic acid biosynthesis via nonsense-mediated mRNA decay, or resulting in a truncated hGNE1 protein, which interferes with normal enzyme function. LRS is expected to be more frequently incorporated in genetic analysis given its efficacy in detecting hard-to-find pathogenic variants.


Assuntos
Éxons , Íntrons , Complexos Multienzimáticos , Trombocitopenia , Humanos , Masculino , Feminino , Complexos Multienzimáticos/genética , Éxons/genética , Íntrons/genética , Adulto , Trombocitopenia/genética , Miopatias Distais/genética , Adulto Jovem , Adolescente , Criança , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Linhagem , Pessoa de Meia-Idade
5.
Clin Chem Lab Med ; 62(4): 682-689, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37870064

RESUMO

OBJECTIVES: Antineutrophil cytoplasmic antibody (ANCA) testing assists clinicians diagnose ANCA-associated vasculitis (AAV). We aimed to verify and harmonize chemiluminescent immunoassays for the detection of myeloperoxidase (MPO)- and proteinase 3 (PR3)-ANCA. METHODS: An in-house ELISA, a capture ELISA, and a chemiluminescent assay QUANTA Flash on a BIO-FLASH analyzer were used to detect MPO- and PR3-ANCA in sera from 39 patients with AAV, 55 patients with various non-AAV, and 66 patients with connective tissue diseases. The results of the assays were evaluated, and their clinical performance was assessed. The precision and linearity of the QUANTA Flash assays were determined, and likelihood ratios (LRs) for AAV at diagnosis were calculated. RESULTS: The precision and linearity of the QUANTA Flash assays were confirmed. Overall agreement between 97.5 and 98.8 % and Cohen's kappa coefficients between 0.861 and 0.947 were observed for the results of the QUANTA Flash assays and ELISAs. The diagnostic sensitivity, specificity, and ROC analysis of the assays for AAV were statistically similar (in-house ELISA 89.7 %, 95.0 %, and 0.937; capture ELISA 92.3 %, 98.3 %, and 0.939; and QUANTA Flash 89.7 %, 95.9 %, and 0.972). For the QUANTA Flash assay results, the interval-specific LRs for AAV at diagnosis were: 0-8 CU had LR 0.08, 8-29 CU had LR 1.03, 29-121 CU had LR 7.76, 121-191 CU had LR 12.4, and >191 CU had LR ∞. CONCLUSIONS: The QUANTA Flash MPO and PR3 assays provide precise and consistent results and have comparable clinical utility for AAV. The calculated LRs were consistent with published LRs, confirming the utility of LRs for harmonization of ANCA results.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Anticorpos Anticitoplasma de Neutrófilos , Humanos , Mieloblastina , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Peroxidase
6.
Plant Cell Environ ; 46(9): 2778-2793, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37381151

RESUMO

Oriented movement (phototaxis) is an efficient way to optimize light-driven processes and to avoid photodamage for motile algae. In Chlamydomonas the receptors for phototaxis are the channelrhodopsins ChR1 and ChR2. Both are directly light-gated, plasma membrane-localized cation channels. To optimally adjust its overall light-dependent responses, Chlamydomonas must tightly control the ChRs cellular abundance and integrate their activities into its general photoprotective network. How this is achieved is largely unknown. Here we show that the ChR1 protein level decreases upon illumination in a light-intensity and quality-dependent manner, whereas it is stable in prolonged darkness. Analysis of knockout strains of six major photoreceptors absorbing in the blue-violet range, which is most effective in evoking ChR1 degradation, revealed that only phototropin (PHOT) is involved. Notably, ChR2 degradation was normal in a ΔPHOT strain. Further, our results indicate that a COP1-SPA1 E3 ubiquitin ligase, the transcription factor Hy5 as well as changes in the cellular redox poise and cyclic nucleotide levels are additional components involved in this light acclimation response of Chlamydomonas. Our data highlight the presence of an adaptive framework connecting phototaxis with general photoprotective mechanisms via the use of overlapping signaling components already at the level of the primary photoreceptor.


Assuntos
Chlamydomonas reinhardtii , Chlamydomonas , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Chlamydomonas reinhardtii/metabolismo , Luz , Chlamydomonas/genética , Transdução de Sinais/fisiologia , Canais Iônicos/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
7.
Bioorg Chem ; 112: 104907, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33979735

RESUMO

The enzyme leucyl-tRNA synthetase (LRS) and the amino acid leucine regulate the mechanistic target of rapamycin (mTOR) signaling pathway. Leucine-dependent mTORC1 activation depends on GTPase activating protein events mediated by LRS. In a prior study, compound BC-LI-0186 was discovered and shown to interfere with the mTORC1 signaling pathway by inhibiting the LRS-RagD interaction. However, BC-LI-0186 exhibited poor solubility and was metabolized by human liver microsomes. In this study, in silico physicochemical properties and metabolite analysis of BC-LI-0186 are used to investigate the addition of functional groups to improve solubility and microsomal stability. In vitro experiments demonstrated that 7b and 8a had improved chemical properties while still maintaining inhibitory activity against mTORC1. The results suggest a new strategy for the discovery of novel drug candidates and the treatment of diverse mTORC1-related diseases.


Assuntos
Inibidores Enzimáticos/farmacologia , Leucina-tRNA Ligase/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Proteínas Monoméricas de Ligação ao GTP/antagonistas & inibidores , Pirazolonas/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Leucina-tRNA Ligase/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Estrutura Molecular , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Pirazolonas/síntese química , Pirazolonas/química , Relação Estrutura-Atividade
8.
J Clean Prod ; 282: 124549, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33041532

RESUMO

The wind energy sector has seen an increasing growth in the last decade and this is foreseen to continue in the next years. This has posed several challenges in terms of skilled and prepared professionals that have always to be up to date in an industry that is constantly changing. Thus, teaching tools have gained an increasing interest. The present research reviewed the state of the art in terms of digital interactive training tools pinpointing that the existing options do not feature the user involvement in the development of the training material. Hence, the main aim of this paper is to develop and test an innovative method based on gamification to increase wind energy sector industrial skills, providing a digital interactive environment in the form of a new user-friendly software that can allow its users to train and contribute to the teaching and learning contents. The first methodological step deals with the associated background studies that were required at strategy implementation and development stages, including market analysis and technology trade-offs, as well as the general structure and the implementation steps of the software design. Obtained results pinpointed that with minimal use of web-based database and network connectivity, a mobile phone application could work in the form of a time-scored quiz application that remotely located staff at wind energy farms could benefit from. The technological innovation brought by this research will substantially improve the service of training, allowing a more dynamic formative management contributing to an improvement in the competitiveness and a step towards excellence for the whole sector.

9.
Bioorg Med Chem ; 27(6): 1099-1109, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30755350

RESUMO

Leucyl-tRNA synthetase (LRS) plays an important role in amino acid-dependent mTORC1 signaling, which is known to be associated with cellular metabolism and proliferation. Therefore, LRS-targeting small molecules that can suppress mTORC1 activation may provide an alternative strategy to current anticancer therapy. In this work, we developed a library of leucyladenylate sulfate analogues by extensively modifying three different pharmacophoric regions comprising adenine, ribose and leucine. Several effective compounds were identified by cell-based mTORC1 activation assays and further tested for anticancer activity. The selected compounds mostly exhibited selective cytotoxicity toward five different cancer cell lines, supporting the hypothesis that the LRS-mediated mTORC1 pathway is a promising alternative target to current therapeutic approaches.


Assuntos
Leucina-tRNA Ligase/metabolismo , Leucina/análogos & derivados , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células HEK293 , Humanos , Leucina/química , Leucina/metabolismo , Leucina/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
10.
Plant Cell Environ ; 41(3): 483-500, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29220548

RESUMO

Haem oxygenase (HO) is a universal enzyme that catalyses stereospecific cleavage of haem to BV IX α and liberates Fe+2 ion and CO as by-product. Beside haem degradation, it has important functions in plants that include cellular defence, stomatal regulation, iron mobilization, phytochrome chromophore synthesis, and lateral root formation. Phytochromes are an extended family of photoreceptors with a molecular mass of 250 kDa and occur as a dimer made up of 2 equivalent subunits of 125 kDa each. Each subunit is made of two components: the chromophore, a light-capturing pigment molecule and the apoprotein. Biosynthesis of phytochrome (phy) chromophore includes the oxidative splitting of haem to biliverdin IX by an enzyme HO, which is the decisive step in the biosynthesis. In photosynthetic organisms, BVα is reduced to 3Z PΦB by a ferredoxin-dependent PΦB synthase that finally isomerised to PΦB. The synthesized PΦB assembles with the phytochrome apoprotein in the cytoplasm to generate holophytochrome. Thus, necessary for photomorphogenesis in plants, which has confirmed from the genetic studies, conducted on Arabidopsis thaliana and pea. Besides the phytochrome chromophore synthesis, the review also emphasises on the current advances conducted in plant HO implying its developmental and defensive role.


Assuntos
Heme Oxigenase (Desciclizante)/química , Heme Oxigenase (Desciclizante)/metabolismo , Fitocromo/metabolismo , Proteínas de Plantas/metabolismo , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biliverdina/metabolismo , Monóxido de Carbono/metabolismo , Clorofila/biossíntese , Cianobactérias/enzimologia , Heme Oxigenase (Desciclizante)/genética , Fotossíntese , Fitocromo/genética , Células Vegetais , Proteínas de Plantas/química , Raízes de Plantas/enzimologia , Raízes de Plantas/crescimento & desenvolvimento , Transdução de Sinais
11.
Cell Biochem Funct ; 36(8): 431-442, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30411383

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) is a causal gene of Parkinson disease. G2019S pathogenic mutation increases its kinase activity. LRRK2 regulates various phenotypes including autophagy, neurite outgrowth, and vesicle trafficking. Leucyl-tRNA synthetase (LRS) attaches leucine to tRNALeu and activates mTORC1. Down-regulation of LRS induces autophagy. We investigated the relationship between LRRK2 and LRS in regulating autophagy and observed interaction between endogenous LRRK2 and LRS proteins and LRS phosphorylation by LRRK2. Mutation studies implicated that T293 in the LRS editing domain was a putative phosphorylation site. Phospho-Thr in LRS was increased in cells overexpressing G2019S and dopaminergic neurons differentiated from induced pluripotent stem (iPS) cells of a G2019S carrier. It was decreased by treatment with an LRRK2 kinase inhibitor (GSK2578215A). Phosphomimetic T293D displayed lower leucine bindings than wild type (WT), suggesting its defective editing function. Cellular expression of T293D increased expression of GRP78/BiP, LC3B-II, and p62 proteins and number of LC3 puncta. Increase of GRP78 and phosphorylated LRS was diminished by treatment with GSK2578215A. Levels of LC3B, GRP78/BiP, p62, and α-synuclein proteins were also increased in G2019S transgenic (TG) mice. These data suggest that LRRK2-mediated LRS phosphorylation impairs autophagy by increasing protein misfolding and endoplasmic reticulum stress mediated by LRS editing defect. SIGNIFICANCE OF THE STUDY: Leucine-rich repeat kinase 2 (LRRK2) is the most common genetic cause of Parkinson disease (PD), and the most prevalent pathogenic mutation, G2019S, increases its kinase activity. In this study, we elucidated that leucyl-tRNA synthetase (LRS) was an LRRK2 kinase substrate and identified T293 as an LRRK2 phosphorylation site. LRRK2-meidated LRS phosphorylation or G2019S can lead to impairment of LRS editing, increased ER stress, and accumulation of autophagy markers. These results demonstrate that LRRK2 kinase activity can facilitate accumulation of misfolded protein, suggesting that LRRK2 kinase might be a potential PD therapeutic target along with previous studies.


Assuntos
Autofagia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Leucina-tRNA Ligase/metabolismo , Sequência de Aminoácidos , Aminopiridinas/farmacologia , Animais , Autofagia/efeitos dos fármacos , Benzamidas/farmacologia , Encéfalo/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Leucina-tRNA Ligase/genética , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Mutagênese Sítio-Dirigida , Fosforilação , Alinhamento de Sequência , alfa-Sinucleína/metabolismo
12.
BMC Evol Biol ; 17(1): 41, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28166714

RESUMO

BACKGROUND: Males and females often have opposing strategies for increasing fitness. Males that out-compete others will acquire more mating opportunities and thus have higher lifetime reproductive success. Females that mate with a high quality male receive either direct benefits through productivity or acquisition of additional resources or indirect benefits through the increased fitness of offspring. These components may be in conflict: factors that increase offspring fitness may decrease a female's productivity, and alleles that are beneficial in one sex may be detrimental in the opposite sex. Here, we use a multigenerational study with recently caught strains of Drosophila melanogaster to examine the relationship between parental, male offspring, and female offspring fitness when fitness is measured in a basal non-competitive environment. RESULTS: We find synergy between parental and offspring lifetime reproductive success, indicating a lack of parent-offspring conflict, and a synergy between son and daughter reproductive success, indicating a lack of intersexual conflict. Interestingly, inbreeding significantly reduced the lifetime reproductive success of daughters, but did not have a significant effect on short-term productivity measures of daughters, sons or parents. CONCLUSIONS: In wild-caught flies, there appears to be no parent-offspring conflict or intersexual conflict for loci influencing offspring production in a anon-competitive environment. Further, there may not be a biologically relevant selection pressure for avoidance of inbreeding depression in wild-type individuals of this short-lived species.


Assuntos
Drosophila melanogaster/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Genótipo , Endogamia , Masculino , Reprodução , Seleção Genética , Fatores Sexuais
13.
Biochem Biophys Res Commun ; 493(2): 1129-1135, 2017 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-28882589

RESUMO

Leucyl-tRNA synthetase (LRS) plays major roles in providing leucine-tRNA and activating mechanistic target of rapamycin complex 1 (mTORC1) through intracellular leucine sensing. mTORC1 activated by amino acids affects the influence on physiology functions including cell proliferation, protein synthesis and autophagy in various organisms. Biochemical results demonstrating leucine sensing have been published, but visual results are lacking. Therefore, we observed the location of LRS with and without leucine using stimulated emission depletion (STED) microscopy one of the super-resolution microscopy and transmission electron microscopy (TEM). This revealed that LRS was translocated to the lysosome on addition of leucine. The translocation was inhibited by treatment with compound BC-LI-0186, disrupting the interaction between RagD and LRS. Immuno-TEM revealed a clear decrease in LRS translocation to the lysosome on addition of the inhibitor. This direct visualization of leucine sensing and LRS translocation to the lysosome was related to mTORC1 activation. To study the relationship between mTORC1 activation and LRS translocation, we monitored the change in autophagy for each condition using TEM and CLSM. The results showed a decrease in autophagy on addition of leucine, demonstrating crosstalk between leucine sensing, LRS translocation, RagD interaction, and mTORC1 activation.


Assuntos
Leucina-tRNA Ligase/metabolismo , Leucina/metabolismo , Lisossomos/metabolismo , Autofagia , Células HEK293 , Células HeLa , Humanos , Leucina-tRNA Ligase/análise , Proteína 2 de Membrana Associada ao Lisossomo/análise , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/ultraestrutura , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Monoméricas de Ligação ao GTP/análise , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/análise , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/análise , Serina-Treonina Quinases TOR/metabolismo
14.
Bioorg Med Chem ; 25(15): 4145-4152, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28625715

RESUMO

Leucyl-tRNA synthetase (LRS) has been reported to be a possible mediator of intracellular amino acids signaling to mTORC1. Given that mTORC1 is associated with cell proliferation and tumorigenesis, the LRS-mediated mTORC1 pathway may offer an alternative strategy in anticancer therapy. In this study, we developed a series of simplified analogues of leucyladenylate sulfamate (1) as LRS-targeted mTORC1 inhibitors. We replaced the adenylate group with a N-(3,4-dimethoxybenzyl)benzenesulfonamide (2a) or a N-(2-phenoxyethyl)benzenesulfonamide groups (2b) that can maintain specific binding, but has more favorable physicochemical properties such as reduced polarity and asymmetric centers. Among these simplified analogues, compound 16 and its constrained analogue 22 effectively inhibited S6K phosphorylation in a dose-dependent manner and exhibited cancer cell specific cytotoxicity against six different types of cancer cells. This result supports that LRS is a viable target for novel anticancer therapy.


Assuntos
Descoberta de Drogas , Leucina-tRNA Ligase/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Espectrometria de Massas/métodos , Fosforilação , Espectroscopia de Prótons por Ressonância Magnética , Proteínas Quinases S6 Ribossômicas/metabolismo
15.
Ecol Lett ; 19(2): 171-179, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26610734

RESUMO

The role of habitat use in generating individual variation in fitness has rarely been examined empirically in natural populations of long-lived mammals, particularly for both sexes simultaneously. This is the case despite the increase in studies attempting to understand evolutionary change in such populations. Using data from the St. Kilda Soay sheep population, we quantified the association between lifetime reproductive performance (lifetime breeding and reproductive success) and the proportion of the home range covered by a key grass species, H. lanatus, for 490 females and 304 males. Increased H. lanatus cover was associated only with increased female lifetime reproductive success, but increased lifetime breeding success for both sexes, arising through increased male longevity and increased female fecundity. This work suggests that improved understanding of the causes and consequences of fitness differences will likely require us to better account for habitat-derived individual variation, and to do so for the sexes appropriately.

16.
Am J Kidney Dis ; 67(6): 834-40, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26830256

RESUMO

Acute kidney injury (AKI) is increasingly recognized as a major health problem worldwide, responsible for an estimated 1.4 million deaths per year. The occurrence of and approach to AKI in low-resource settings (LRS) present special challenges due to often limited health care resources, including insufficient numbers of trained personnel, diagnostic tools, and treatment options. Although the International Society of Nephrology set a goal of eliminating preventable deaths from AKI by 2025, implementation of this program in LRS presents major challenges not only because of the lack of resources, but also because of the lack of awareness of the impact of AKI on patient outcomes, factors that are complicated by the challenge of cognitively dissociating the care of patients with AKI from the care of patients with chronic kidney failure. To better understand how to increase the awareness of AKI and develop strategies to improve the identification and treatment of patients with AKI in LRS, we administered an 18-item web-based questionnaire to physicians actively engaged in providing nephrology care in LRS. A checklist was then developed of meaningful and targeted approaches for implementation, with focus on engaging local and regional stakeholders, developing education programs and appropriate guidelines, enhancing training of health care workers, expanding health care resources, linking with other regional health care projects, and broadening research opportunities.


Assuntos
Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Recursos em Saúde , Acessibilidade aos Serviços de Saúde , Injúria Renal Aguda/epidemiologia , Países em Desenvolvimento , Humanos , Melhoria de Qualidade
17.
Z Kinder Jugendpsychiatr Psychother ; 43(3): 195-205, 2015 May.
Artigo em Alemão | MEDLINE | ID: mdl-26098007

RESUMO

OBJECTIVE: Visual perceptual abilities are increasingly being neglected in research concerning reading disabilities. This study measures the visual perceptual abilities of children with disabilities in reading. METHOD: The visual perceptual abilities of 35 children with specific reading disorder and 30 controls were compared using the German version of the Developmental Test of Visual Perception ­ Adolescent and Adult (DTVP-A). RESULTS: 11 % of the children with specific reading disorder show clinically relevant performance on the DTVP-A. The perceptual abilities of both groups differ significantly. No significant group differences exist after controlling for general IQ or Perceptional Reasoning Index, but they do remain after controlling for Verbal Comprehension, Working Memory, and Processing Speed Index. CONCLUSIONS: The number of children with reading difficulties suffering from visual perceptual disorders has been underestimated. For this reason, visual perceptual abilities should always be tested when making a reading disorder diagnosis. Profiles of IQ-test results of children suffering from reading and visual perceptual disorders should be interpreted carefully.


Assuntos
Dislexia/diagnóstico , Dislexia/psicologia , Transtornos da Percepção/diagnóstico , Transtornos da Percepção/psicologia , Percepção Visual , Adolescente , Criança , Compreensão , Feminino , Humanos , Inteligência , Masculino , Memória de Curto Prazo , Testes Neuropsicológicos/estatística & dados numéricos , Psicometria , Tempo de Reação , Aprendizagem Verbal
18.
Z Kinder Jugendpsychiatr Psychother ; 42(4): 233-41, 2014 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-25005901

RESUMO

OBJECTIVE: This study examined the degree and manner of involving parents in the treatment of dyslexic children. The study also identified therapeutic variables predicting the extent of parent involvement and the reasons for any instances of failed involvement. METHOD: A sample of 53 out of 120 randomly selected German dyslexia therapists (response rate: 44 %) filled out a paper-pencil questionnaire assessing the degree and manner of parent involvement in the treatment of dyslexic children. Furthermore, therapists' attitudes toward parent involvement and their subjective competence when working with parents were assessed. RESULTS: The most common forms of parent involvement occurred during anamnesis and when drawing up recommendations for home exercises. The therapists' attitudes toward working with parents predicted the extent of parent involvement (ß = .58). There was a significant correlation between working with parents and the subjective competence of the therapist (r = .28), which was mediated by therapists' attitudes toward parent involvement. Disinterest on the part of parents and therapists' lack of time proved to be reasons for less parent involvement. DISCUSSION: Despite declared positive attitudes toward working with parents, the involvement of parents in the therapeutic process by therapists was limited.


Assuntos
Participação da Comunidade , Dislexia/psicologia , Dislexia/terapia , Poder Familiar/psicologia , Inquéritos e Questionários , Adulto , Atitude , Criança , Feminino , Alemanha , Visita Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade , Competência Profissional , Relações Profissional-Família , Prognóstico , Psicometria
19.
Transfus Med Rev ; : 150836, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38851986

RESUMO

The objective of this study was to devise a novel approach for determining MNS blood group utilizing long-read sequencing (LRS) and to identify intricate genome variations associated with this blood group system. In this study, a total of 60 blood samples were collected from randomly selected Chinese Han blood donors. The amplification of the full-length sequences of GYPA exon 2-7 (11 kb) and GYPB exon 2-6 (7 kb) was conducted on the blood samples obtained from these 60 donors. Subsequently, the sequencing of these amplified sequences was performed using the PacBio platform. The obtained sequencing data were then compared with the reference sequence of the human genome (GRCh38) utilizing the pbmm2 software, resulting in the acquisition of the haploid sequences of GYPA and GYPB. The serological typing prediction was conducted using the International Society of Blood Transfusion (ISBT) database, while the analysis of SNVs sites was performed using deepvariant v1.2.0 software and reference sequence alignment. A total of 60 samples yielded unambiguous high-quality haplotypes, which can serve as a standardized reference sequence for molecular biology typing of MNSs in the Chinese population. In a total of 60 serological samples, the LRS method successfully identified the M, N, S, and s blood group antigens by analyzing specific genetic variations (c.59, c.71, c.72 for GYPA, and c.143 for GYPB), which aligned with the results obtained through conventional serological techniques. 4 Mur samples that had been previously validated through serology and molecular biology were successfully confirmed, and complete haploid sequences were obtained. Notably, one of the Mur samples exhibited a novel breakpoint, GYP (B1-136-B ψ 137-212-A213-229-B230-366), thereby representing a newly identified subtype. Single molecule sequencing, which eliminates the necessity for PCR amplification, effectively encompasses GC and high repeat regions, enhancing accuracy in quantifying mutations with low abundance or frequency. By employing LRS analysis of the core region of GYPA and GYPB, diverse genotypes of MNS can be precisely and reliably identified in a single assay. This approach presents a comprehensive, expeditious, and precise novel method for the categorization and investigation of MNS blood group system.

20.
Sci Rep ; 14(1): 10239, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702340

RESUMO

The classification of locally rotationally symmetric Bianchi type V spacetime based on its killing vector fields is presented in this paper using an algebraic method. In this approach, a Maple algorithm is employed to transform the Killing's equations into a reduced evolutive form. Subsequently, the integration of the Killing's equations is carried out subject to the constraints provided by the algorithm. The algorithm demonstrates that there exist fifteen distinct metrics that could potentially possess Killing vector fields. Upon solving the Killing equations for all fifteen metrics, it is observed that seven out of the fifteen metrics exclusively exhibit the minimum number of Killing vector fields. The remaining eight metrics admit a varying number of Killing vector fields, specifically 6, 7, or 10. The Kretschmann scalar has been computed for each of the obtained metrics, revealing that all of them possess a finite Kretschmann scalar and thus exhibit regular behavior.

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