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1.
Nature ; 578(7795): 449-454, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051587

RESUMO

The solid tumour microenvironment includes nerve fibres that arise from the peripheral nervous system1,2. Recent work indicates that newly formed adrenergic nerve fibres promote tumour growth, but the origin of these nerves and the mechanism of their inception are unknown1,3. Here, by comparing the transcriptomes of cancer-associated trigeminal sensory neurons with those of endogenous neurons in mouse models of oral cancer, we identified an adrenergic differentiation signature. We show that loss of TP53 leads to adrenergic transdifferentiation of tumour-associated sensory nerves through loss of the microRNA miR-34a. Tumour growth was inhibited by sensory denervation or pharmacological blockade of adrenergic receptors, but not by chemical sympathectomy of pre-existing adrenergic nerves. A retrospective analysis of samples from oral cancer revealed that p53 status was associated with nerve density, which was in turn associated with poor clinical outcomes. This crosstalk between cancer cells and neurons represents mechanism by which tumour-associated neurons are reprogrammed towards an adrenergic phenotype that can stimulate tumour progression, and is a potential target for anticancer therapy.


Assuntos
Neurônios Adrenérgicos/patologia , Transdiferenciação Celular , Reprogramação Celular , Neoplasias Bucais/patologia , Células Receptoras Sensoriais/patologia , Proteína Supressora de Tumor p53/deficiência , Antagonistas Adrenérgicos/farmacologia , Antagonistas Adrenérgicos/uso terapêutico , Animais , Divisão Celular , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Fibras Nervosas/patologia , Neuritos/patologia , Receptores Adrenérgicos/metabolismo , Estudos Retrospectivos , Microambiente Tumoral , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Genome Res ; 32(5): 916-929, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35301263

RESUMO

Genetic variants drive the evolution of traits and diseases. We previously modeled these variants as small displacements in fitness landscapes and estimated their functional impact by differentiating the evolutionary relationship between genotype and phenotype. Conversely, here we integrate these derivatives to identify genes steering specific traits. Over cancer cohorts, integration identified 460 likely tumor-driving genes. Many have literature and experimental support but had eluded prior genomic searches for positive selection in tumors. Beyond providing cancer insights, these results introduce a general calculus of evolution to quantify the genotype-phenotype relationship and discover genes associated with complex traits and diseases.


Assuntos
Cálculos , Neoplasias , Evolução Biológica , Aptidão Genética , Genótipo , Humanos , Modelos Genéticos , Neoplasias/genética , Fenótipo , Seleção Genética
3.
Curr Issues Mol Biol ; 46(7): 6620-6632, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39057036

RESUMO

In cattle, the corpus luteum (CL) is pivotal in maintaining early pregnancy by secreting progesterone. To establish pregnancy, the conceptus produces interferon-τ, preventing luteolysis and initiating the transformation of the CL spurium into a CL verum. Although this transformation is tightly regulated, limited data are available on the expression of microRNAs (miRNAs) during and after this process. To address this gap, we re-analyzed previously published RNA-Seq data of CL from pregnant cows and regressed CL from non-pregnant cows. This analysis identified 44 differentially expressed miRNAs. From this pool, three miRNAs-bta-miR-222-3p, bta-miR-29c, and bta-miR-2411-3p-were randomly selected for relative quantification. Using bovine ovaries (n = 14) obtained from an abattoir, total RNA (including miRNAs) was extracted and converted to cDNA for RT-qPCR. The results revealed that bta-miR-222-3p was downregulated (p = 0.016) in pregnant females compared to non-pregnant cows with regressed CL. However, no differences in miRNA expression were observed between CL of pregnant and non-pregnant cows for bta-miR-29c (p > 0.32) or bta-miR-2411-3p (p > 0.60). In silico prediction approaches indicated that these miRNAs are involved in pathways regulating pregnancy maintenance, such as the VEGF- and FoxO-signaling pathways. Additionally, their biogenesis is regulated by GABPA and E2F4 transcription factors. The validation of selected miRNA expression in the CL during pregnancy by RT-qPCR provides novel insights that could potentially lead to the identification of biomarkers related to CL physiology and pregnancy outcome.

4.
PLoS Pathog ; 18(5): e1010485, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35587473

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is an important human pathogen. In cell culture, CCHFV is sensed by the cytoplasmic RNA sensor retinoic acid-inducible gene I (RIG-I) molecule and its adaptor molecule mitochondrial antiviral signaling (MAVS) protein. MAVS initiates both type I interferon (IFN-I) and proinflammatory responses. Here, we studied the role MAVS plays in CCHFV infection in mice in both the presence and absence of IFN-I activity. MAVS-deficient mice were not susceptible to CCHFV infection when IFN-I signaling was active and showed no signs of disease. When IFN-I signaling was blocked by antibody, MAVS-deficient mice lost significant weight, but were uniformly protected from lethal disease, whereas all control mice succumbed to infection. Cytokine activity in the infected MAVS-deficient mice was markedly blunted. Subsequent investigation revealed that CCHFV infected mice lacking TNF-α receptor signaling (TNFA-R-deficient), but not IL-6 or IL-1 activity, had more limited liver injury and were largely protected from lethal outcomes. Treatment of mice with an anti-TNF-α neutralizing antibody also conferred partial protection in a post-virus exposure setting. Additionally, we found that a disease causing, but non-lethal strain of CCHFV produced more blunted inflammatory cytokine responses compared to a lethal strain in mice. Our work reveals that MAVS activation and cytokine production both contribute to CCHFV pathogenesis, potentially identifying new therapeutic targets to treat this disease.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Animais , Citocinas , Modelos Animais de Doenças , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Camundongos , Camundongos Knockout , Índice de Gravidade de Doença , Inibidores do Fator de Necrose Tumoral
5.
Langmuir ; 40(8): 4228-4235, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38357880

RESUMO

Simple synthetic and natural hydrogels can be formulated to have elastic moduli that match biological tissues, leading to their widespread application as model systems for tissue engineering, medical device development, and drug delivery vehicles. However, two different hydrogels having the same elastic modulus but differing in microstructure or nanostructure can exhibit drastically different mechanical responses, including their poroelasticity, lubricity, and load bearing capabilities. Here, we investigate the mechanical response of collagen-1 networks to local and bulk compressive loads. We compare these results to the behavior of polyacrylamide, a fundamentally different class of hydrogel network consisting of flexible polymer chains. We find that the high bending rigidity of collagen fibers, which suppresses entropic bending fluctuations and osmotic pressure, facilitates the bulk compression of collagen networks under infinitesimal applied stress. These results are fundamentally different from the behavior of flexible polymer networks in which the entropic thermal fluctuations of the polymer chains result in an osmotic pressure that must first be overcome before bulk compression can occur. Furthermore, we observe minimal transverse strain during the axial loading of collagen networks, a behavior reminiscent of open-celled cellular solids. Inspired by these results, we applied mechanical models of cellular solids to predict the elastic moduli of the collagen networks and found agreement with the moduli values measured through contact indentation. Collectively, these results suggest that unlike flexible polymer networks that are often considered incompressible, collagen hydrogels behave like rigid porous solids that volumetrically compress and expel water rather than spreading laterally under applied normal loads.


Assuntos
Colágeno , Matriz Extracelular , Pressão , Módulo de Elasticidade , Colágeno/química , Polímeros , Hidrogéis/química , Estresse Mecânico
6.
J Inherit Metab Dis ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39038845

RESUMO

ALDH7A1 deficiency is an epileptic encephalopathy whose seizures respond to treatment with supraphysiological doses of pyridoxine. It arises as a result of damaging variants in ALDH7A1, a gene in the lysine catabolism pathway. α-Aminoadipic semialdehyde (α-AASA) and Δ1-piperideine-6-carboxylate (P6C), which accumulate because of the block in the lysine pathway, are diagnostic biomarkers for this disorder. Recently, it has been reported that 6-oxo-pipecolic acid (6-oxo-PIP) also accumulates in the urine, CSF and plasma of ALDH7A1-deficient individuals and that, given its improved stability, it may be a more suitable biomarker for this disorder. This study measured 6-oxo-PIP in urine from a cohort of 30 patients where α-AASA was elevated and showed that it was above the normal range in all those above 6 months of age. However, 6-oxo-PIP levels were within the normal range in 33% of the patients below 6 months of age. Levels increased with age and correlated with a decrease in α-AASA levels. Longitudinal analysis of urine samples from ALDH7A1-deficient patients who were on a lysine restricted diet whilst receiving supraphysiological doses of pyridoxine showed that levels of 6-oxo-PIP remained elevated whilst α-AASA decreased. Similar to α-AASA, we found that elevated urinary excretion of 6-oxo-PIP can also occur in individuals with molybdenum cofactor deficiency. This study demonstrates that urinary 6-oxo-PIP may not be a suitable biomarker for ALDH7A1 deficiency in neonates. However, further studies are needed to understand the biochemistry leading to its accumulation and its potential long-term side effects.

7.
Opt Lett ; 48(3): 578-581, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723535

RESUMO

We report experimental observation of subharmonic mode excitation in primary Kerr optical frequency combs generated using crystalline whispering-gallery mode resonators. We show that the subcombs can be controlled and span a single or multiple free spectral ranges around the primary comb modes. In the spatial domain, the resulting multiscale combs correspond to an amplitude modulation of intracavity roll patterns. We perform a theoretical analysis based on eigenvalue decomposition that evidences the mechanism leading to the excitation of these combs.

8.
Exp Eye Res ; 236: 109647, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37689341

RESUMO

The retinoic acid-inducible gene I (RIG)-I-like receptor (RLR) family of RNA sensor proteins plays a key role in the innate immune response to viral nucleic acids, including viral gene delivery vectors, but little is known about the expression of RLR proteins in the retina. The purpose of this study was to characterize cell-specific expression patterns of RLR proteins in non-human primate (NHP) neural retina tissue and to examine if RLR pathway signaling restricts viral gene delivery transduction. Since RLR protein signaling converges at the mitochondrial antiviral signaling protein (MAVS), experiments were performed to determine if knockdown of MAVS affected FIVGFP transduction efficiency in the human Mueller cell line MIO-M1. Immunoblotting confirmed expression of RIG-I, melanoma differentiation-associated protein 5 (MDA5), laboratory of genetics and physiology 2 (LGP2), and MAVS proteins in MIO-M1 cells and NHP retina tissue. Double label immunofluorescence (IF) studies revealed RIG-I, LGP2, and MAVS were expressed in Mueller microglial cells in the NHP retina. In addition, LGP2 and MDA5 proteins were detected in cone and retinal ganglion cells (RGC). MDA5 was also present in a subset of calretinin positive amacrine cells, and in nuclei within the inner nuclear layer (INL). Knockdown of MAVS significantly increased the transduction efficiency of the lentiviral vector FIVGFP in MIO-M1 cells, compared to control cells. FIVGFP or AAVGFP challenge did not alter expression of the LGP2, MAVS, MDA5 or RIG-I genes in MIO-M1 cells or NHP retina tissue compared to media treated controls. Our data demonstrate that innate immune response proteins involved in viral RNA sensing, including MDA5, RIG-I, LGP2, and MAVS, are expressed in several cell types within the NHP neural retina. In addition, the MAVS protein restricts non-human lentiviral transduction efficiency in MIO-M1 cells.


Assuntos
Imunidade Inata , Transdução de Sinais , Animais , Humanos , Retina , Antivirais
9.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37930120

RESUMO

Diaphorina citri is the hemipteran pest and vector of a devastating bacterial pathogen of citrus worldwide. In addition to the two core bacterial endosymbionts of D. citri, Candidatus Carsonella ruddii and Candidatus Profftella armatura, the genome of a novel endosymbiont and as of yet undescribed microbe was discovered in a Hawaiian D. citri population through deep sequencing of multiple D. citri populations. Found to be closely related to the genus Asaia in the family Acetobacteraceae by 16S rRNA gene sequence analysis, it forms a sister clade along with other insect-associated 16S rRNA gene sequences from uncultured bacterium found associated with Aedes koreicus and Sogatella furcifera. Multilocus sequence analysis confirmed the phylogenetic placement sister to the Asaia clade. Despite the culturable Asaia clade being the closest phylogenetic neighbour, attempts to culture this newly identified bacterial endosymbiont were unsuccessful. On the basis of these distinct genetic differences, the novel endosymbiont is proposed to be classified into a candidate genus and species 'Candidatus Kirkpatrickella diaphorinae'. The full genome was deposited in GenBank (accession number CP107052; prokaryotic 16S rRNA OP600170).


Assuntos
Citrus , Hemípteros , Animais , Simbiose , Havaí , RNA Ribossômico 16S/genética , Filogenia , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Bactérias/genética , Hemípteros/microbiologia
10.
Dev Biol ; 480: 62-68, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34400136

RESUMO

The onset of circulation in a developing embryo requires intact blood vessels to prevent hemorrhage. The development of endothelial cells, and their subsequent recruitment of perivascular mural cells are important processes to establish and maintain vascular integrity. These processes are genetically controlled during development, and mutations that affect endothelial cell specification, pattern formation, or maturation through the addition of mural cells can result in early developmental hemorrhage. We created a strong loss of function allele of the zebrafish GDP-mannose 4,6 dehydratase (gmds) gene that is required for the de novo synthesis of GDP-fucose, and homozygous embryos display cerebral hemorrhages. Our data demonstrate that gmds mutants have early defects in vascular patterning with ectopic branches observed at time of hemorrhage. Subsequently, defects in the number of mural cells that line the vasculature are observed. Moreover, activation of Notch signaling rescued hemorrhage phenotypes in gmds mutants, highlighting a potential downstream pathway that requires protein fucosylation for vascular integrity. Finally, supplementation with fucose can rescue hemorrhage frequency in gmds mutants, demonstrating that synthesis of GDP-fucose via an alternative (salvage) pathway may provide an avenue toward therapeutic correction of phenotypes observed due to defects in de novo GDP-fucose synthesis. Together, these data are consistent with a novel role for the de novo and salvage protein fucosylation pathways in regulating vascular integrity through a Notch dependent mechanism.


Assuntos
Células Endoteliais/metabolismo , Hidroliases/metabolismo , Receptores Notch/metabolismo , Animais , Padronização Corporal/genética , Diferenciação Celular/genética , Movimento Celular/genética , Fucose/metabolismo , Glicosilação , Guanosina Difosfato Fucose/metabolismo , Hemorragia/genética , Hemorragia/prevenção & controle , Hidroliases/genética , Mutação com Perda de Função/genética , Mutação , Fenótipo , Receptores Notch/fisiologia , Transdução de Sinais , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
11.
Hum Genet ; 141(3-4): 431-444, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35278131

RESUMO

Sequencing exomes/genomes have been successful for identifying recessive genes; however, discovery of dominant genes including deafness genes (DFNA) remains challenging. We report a new DFNA gene, ATP11A, in a Newfoundland family with a variable form of bilateral sensorineural hearing loss (SNHL). Genome-wide SNP genotyping linked SNHL to DFNA33 (LOD = 4.77), a locus on 13q34 previously mapped in a German family with variable SNHL. Whole-genome sequencing identified 51 unremarkable positional variants on 13q34. Continuous clinical ascertainment identified several key recombination events and reduced the disease interval to 769 kb, excluding all but one variant. ATP11A (NC_000013.11: chr13:113534963G>A) is a novel variant predicted to be a cryptic donor splice site. RNA studies verified in silico predictions, revealing the retention of 153 bp of intron in the 3' UTR of several ATP11A isoforms. Two unresolved families from Israel were subsequently identified with a similar, variable form of SNHL and a novel duplication (NM_032189.3:c.3322_3327+2dupGTCCAGGT) in exon 28 of ATP11A extended exon 28 by 8 bp, leading to a frameshift and premature stop codon (p.Asn1110Valfs43Ter). ATP11A is a type of P4-ATPase that transports (flip) phospholipids from the outer to inner leaflet of cell membranes to maintain asymmetry. Haploinsufficiency of ATP11A, the phospholipid flippase that specially transports phosphatidylserine (PS) and phosphatidylethanolamine (PE), could leave cells with PS/PE at the extracellular side vulnerable to phagocytic degradation. Given that surface PS can be pharmaceutically targeted, hearing loss due to ATP11A could potentially be treated. It is also likely that ATP11A is the gene underlying DFNA33.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Regiões 3' não Traduzidas , Transportadores de Cassetes de Ligação de ATP/genética , Surdez/genética , Perda Auditiva/genética , Perda Auditiva Neurossensorial/genética , Mutação , Linhagem , Fosfolipídeos/metabolismo , Sítios de Splice de RNA
12.
Hum Genet ; 141(3-4): 965-979, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34633540

RESUMO

Otosclerosis is a bone disorder of the otic capsule and common form of late-onset hearing impairment. Considered a complex disease, little is known about its pathogenesis. Over the past 20 years, ten autosomal dominant loci (OTSC1-10) have been mapped but no genes identified. Herein, we map a new OTSC locus to a 9.96 Mb region within the FOX gene cluster on 16q24.1 and identify a 15 bp coding deletion in Forkhead Box L1 co-segregating with otosclerosis in a Caucasian family. Pre-operative phenotype ranges from moderate to severe hearing loss to profound sensorineural loss requiring a cochlear implant. Mutant FOXL1 is both transcribed and translated and correctly locates to the cell nucleus. However, the deletion of 5 residues in the C-terminus of mutant FOXL1 causes a complete loss of transcriptional activity due to loss of secondary (alpha helix) structure. FOXL1 (rs764026385) was identified in a second unrelated case on a shared background. We conclude that FOXL1 (rs764026385) is pathogenic and causes autosomal dominant otosclerosis and propose a key inhibitory role for wildtype Foxl1 in bone remodelling in the otic capsule. New insights into the molecular pathology of otosclerosis from this study provide molecular targets for non-invasive therapeutic interventions.


Assuntos
Otosclerose , Fatores de Transcrição Forkhead/genética , Humanos , Otosclerose/genética
13.
Genome Res ; 29(9): 1389-1401, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31481461

RESUMO

Low copy repeats (LCRs) are recognized as a significant source of genomic instability, driving genome variability and evolution. The Chromosome 22 LCRs (LCR22s) mediate nonallelic homologous recombination (NAHR) leading to the 22q11 deletion syndrome (22q11DS). However, LCR22s are among the most complex regions in the genome, and their structure remains unresolved. The difficulty in generating accurate maps of LCR22s has also hindered localization of the deletion end points in 22q11DS patients. Using fiber FISH and Bionano optical mapping, we assembled LCR22 alleles in 187 cell lines. Our analysis uncovered an unprecedented level of variation in LCR22s, including LCR22A alleles ranging in size from 250 to 2000 kb. Further, the incidence of various LCR22 alleles varied within different populations. Additionally, the analysis of LCR22s in 22q11DS patients and their parents enabled further refinement of the rearrangement site within LCR22A and -D, which flank the 22q11 deletion. The NAHR site was localized to a 160-kb paralog shared between the LCR22A and -D in seven 22q11DS patients. Thus, we present the most comprehensive map of LCR22 variation to date. This will greatly facilitate the investigation of the role of LCR variation as a driver of 22q11 rearrangements and the phenotypic variability among 22q11DS patients.


Assuntos
Síndrome da Deleção 22q11/genética , Mapeamento Cromossômico/métodos , Cromossomos Humanos Par 22/genética , Sequências Repetitivas de Ácido Nucleico , Animais , Linhagem Celular , Instabilidade Cromossômica , Evolução Molecular , Humanos , Hibridização in Situ Fluorescente , Primatas/genética
14.
Mol Genet Metab ; 135(4): 350-356, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35279367

RESUMO

BACKGROUND: Seventy-five percent of patients with pyridoxine-dependent epilepsy due to α-aminoadipic semialdehyde dehydrogenase deficiency (PDE-ALDH7A1) suffer intellectual developmental disability despite pyridoxine treatment. Adjunct lysine reduction therapies (LRT), aimed at lowering putative neurotoxic metabolites, are associated with improved cognitive outcomes. However, possibly due to timing of treatment, not all patients have normal intellectual function. METHODS: This retrospective, multi-center cohort study evaluated the effect of timing of pyridoxine monotherapy and pyridoxine with adjunct LRT on neurodevelopmental outcome. Patients with confirmed PDE-ALDH7A1 with at least one sibling with PDE-ALDH7A1 and a difference in age at treatment initiation were eligible and identified via the international PDE registry, resulting in thirty-seven patients of 18 families. Treatment regimen was pyridoxine monotherapy in ten families and pyridoxine with adjunct LRT in the other eight. Primary endpoints were standardized and clinically assessed neurodevelopmental outcomes. Clinical neurodevelopmental status was subjectively assessed over seven domains: overall neurodevelopment, speech/language, cognition, fine and gross motor skills, activities of daily living and behavioral/psychiatric abnormalities. RESULTS: The majority of early treated siblings on pyridoxine monotherapy performed better than their late treated siblings on the clinically assessed domain of fine motor skills. For siblings on pyridoxine and adjunct LRT, the majority of early treated siblings performed better on clinically assessed overall neurodevelopment, cognition, and behavior/psychiatry. Fourteen percent of the total cohort was assessed as normal on all domains. CONCLUSION: Early treatment with pyridoxine and adjunct LRT may be beneficial for neurodevelopmental outcome. When evaluating a more extensive neurodevelopmental assessment, the actual impairment rate may be higher than the 75% reported in literature. TAKE- HOME MESSAGE: Early initiation of lysine reduction therapies adjunct to pyridoxine treatment in patients with PDE-ALDH7A1 may result in an improved neurodevelopmental outcome.


Assuntos
Lisina , Piridoxina , Atividades Cotidianas , Estudos de Coortes , Epilepsia , Humanos , Piridoxina/uso terapêutico , Estudos Retrospectivos
15.
Opt Express ; 30(8): 13184-13196, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472938

RESUMO

In this article, we study how the choice of parameters of a slow saturable absorber (SSA) affects the stable operation of a soliton fiber comb laser. We show that a shorter recovery time for the SSA does not always lead to shorter modelocked pulses. Instead, increasing the cavity gain plays a critical role in generating stable modelocked pulses with higher energy and shorter durations. We find that more stable, shorter, and more energetic output pulses can be achieved with lower saturation energies of the SSA and/or higher anomalous dispersion within the cavity.

16.
Circ Res ; 126(3): 330-346, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31739742

RESUMO

Rationale: Genome-wide association studies have identified genetic loci associated with insulin resistance (IR) but pinpointing the causal genes of a risk locus has been challenging. Objective: To identify candidate causal genes for IR, we screened regional and biologically plausible genes (16 in total) near the top 10 IR-loci in risk-relevant cell types, namely preadipocytes and adipocytes. Methods and Results: We generated 16 human Simpson-Golabi-Behmel syndrome preadipocyte knockout lines each with a single IR-gene knocked out by lentivirus-mediated CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 system. We evaluated each gene knockout by screening IR-relevant phenotypes in the 3 insulin-sensitizing mechanisms, including adipogenesis, lipid metabolism, and insulin signaling. We performed genetic analyses using data on the genotype-tissue expression portal expression quantitative trait loci database and accelerating medicines partnership type 2 diabetes mellitus Knowledge Portal to evaluate whether candidate genes prioritized by our in vitro studies were expression quantitative trait loci genes in human subcutaneous adipose tissue, and whether expression of these genes is associated with risk of IR, type 2 diabetes mellitus, and cardiovascular diseases. We further validated the functions of 3 new adipose IR genes by overexpression-based phenotypic rescue in the Simpson-Golabi-Behmel syndrome preadipocyte knockout lines. Twelve genes, PPARG, IRS-1, FST, PEPD, PDGFC, MAP3K1, GRB14, ARL15, ANKRD55, RSPO3, COBLL1, and LYPLAL1, showed diverse phenotypes in the 3 insulin-sensitizing mechanisms, and the first 7 of these genes could affect all the 3 mechanisms. Five out of 6 expression quantitative trait loci genes are among the top candidate causal genes and the abnormal expression levels of these genes (IRS-1, GRB14, FST, PEPD, and PDGFC) in human subcutaneous adipose tissue could be associated with increased risk of IR, type 2 diabetes mellitus, and cardiovascular disease. Phenotypic rescue by overexpression of the candidate causal genes (FST, PEPD, and PDGFC) in the Simpson-Golabi-Behmel syndrome preadipocyte knockout lines confirmed their function in adipose IR. Conclusions: Twelve genes showed diverse phenotypes indicating differential roles in insulin sensitization, suggesting mechanisms bridging the association of their genomic loci with IR. We prioritized PPARG, IRS-1, GRB14, MAP3K1, FST, PEPD, and PDGFC as top candidate genes. Our work points to novel roles for FST, PEPD, and PDGFC in adipose tissue, with consequences for cardiometabolic diseases.


Assuntos
Adipócitos/metabolismo , Resistência à Insulina/genética , Locos de Características Quantitativas , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular , Dipeptidases/genética , Folistatina/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Mutação com Perda de Função , Linfocinas/genética , MAP Quinase Quinase Quinase 1/genética , PPAR gama/genética , Fator de Crescimento Derivado de Plaquetas/genética
17.
Biomacromolecules ; 23(2): 497-504, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-34914371

RESUMO

Exploring novel materials with ice recrystallization inhibition (IRI) activity in several fields often starts with a quantitative analysis of ice crystal size change by a splat assay or sandwich assay on a short time scale from 0.5 to 1 h. This study found that this time scale was insufficient to evaluate the IRI activity of cellulose nanocrystals (CNCs) in a model ice cream system-25.0% sucrose solution. No IRI activity was observed in CNCs incubated with ice crystals on a short time scale of 0.5-2.0 h. However, over longer time scales, the growth of ice crystals was entirely inhibited by 1.0% CNCs (between 2 and 24 h) and 0.5% CNCs (between 24 and 72 h) with corresponding final crystal sizes of 25 and 40 µm, respectively. Additionally, ice shaping was observed on a long exposure time, but not on a short exposure time. The findings presented here can be explained by a time-dependent surface coverage of CNCs on ice crystals. The data here indicate the importance of choosing a suitable exposure time for evaluating the IRI activity of new materials and prompt a better understanding of IRI mechanisms involving CNCs.


Assuntos
Celulose , Nanopartículas , Bioensaio , Celulose/química , Cristalização , Nanopartículas/química , Sacarose
18.
Cancer ; 127(4): 544-553, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33146897

RESUMO

BACKGROUND: The incidence of oral tongue squamous cell carcinoma (OTSCC) is increasing among younger birth cohorts. The etiology of early-onset OTSCC (diagnosed before the age of 50 years) and cancer driver genes remain largely unknown. METHODS: The Sequencing Consortium of Oral Tongue Cancer was established through the pooling of somatic mutation data of oral tongue cancer specimens (n = 227 [107 early-onset cases]) from 7 studies and The Cancer Genome Atlas. Somatic mutations at microsatellite loci and Catalog of Somatic Mutations in Cancer mutation signatures were identified. Cancer driver genes were identified with the MutSigCV and WITER algorithms. Mutation comparisons between early- and typical-onset OTSCC were evaluated via linear regression with adjustments for patient-related factors. RESULTS: Two novel driver genes (ATXN1 and CDC42EP1) and 5 previously reported driver genes (TP53, CDKN2A, CASP8, NOTCH1, and FAT1) were identified. Six recurrent mutations were identified, with 4 occurring in TP53. Early-onset OTSCC had significantly fewer nonsilent mutations even after adjustments for tobacco use. No associations of microsatellite locus mutations and mutation signatures with the age of OTSCC onset were observed. CONCLUSIONS: This international, multicenter consortium is the largest study to characterize the somatic mutational landscape of OTSCC and the first to suggest differences by age of onset. This study validates multiple previously identified OTSCC driver genes and proposes 2 novel cancer driver genes. In analyses by age, early-onset OTSCC had a significantly smaller somatic mutational burden that was not explained by differences in tobacco use. LAY SUMMARY: This study identifies 7 specific areas in the human genetic code that could be responsible for promoting the development of tongue cancer. Tongue cancer in young patients (under the age of 50 years) has fewer overall changes to the genetic code in comparison with tongue cancer in older patients, but the authors do not think that this is due to differences in smoking rates between the 2 groups. The cause of increasing cases of tongue cancer in young patients remains unclear.


Assuntos
Mutação/genética , Oncogenes/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Uso de Tabaco/efeitos adversos , Adulto Jovem
19.
J Gen Virol ; 102(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33961540

RESUMO

SARS-CoV-2 is the causative agent of COVID-19 and human infections have resulted in a global health emergency. Small animal models that reproduce key elements of SARS-CoV-2 human infections are needed to rigorously screen candidate drugs to mitigate severe disease and prevent the spread of SARS-CoV-2. We and others have reported that transgenic mice expressing the human angiotensin-converting enzyme 2 (hACE2) viral receptor under the control of the Keratin 18 (K18) promoter develop severe and lethal respiratory disease subsequent to SARS-CoV-2 intranasal challenge. Here we report that some infected mice that survive challenge have residual pulmonary damages and persistent brain infection on day 28 post-infection despite the presence of anti-SARS-COV-2 neutralizing antibodies. Because of the hypersensitivity of K18-hACE2 mice to SARS-CoV-2 and the propensity of virus to infect the brain, we sought to determine if anti-infective biologics could protect against disease in this model system. We demonstrate that anti-SARS-CoV-2 human convalescent plasma protects K18-hACE2 against severe disease. All control mice succumbed to disease by day 7; however, all treated mice survived infection without observable signs of disease. In marked contrast to control mice, viral antigen and lesions were reduced or absent from lungs and absent in brains of antibody-treated mice. Our findings support the use of K18-hACE2 mice for protective efficacy studies of anti-SARS-CoV-2 medical countermeasures (MCMs). They also support the use of this system to study SARS-CoV-2 persistence and host recovery.


Assuntos
COVID-19/terapia , Lesão Pulmonar Aguda/prevenção & controle , Lesão Pulmonar Aguda/virologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Encéfalo/patologia , Encéfalo/virologia , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Modelos Animais de Doenças , Feminino , Humanos , Imunização Passiva , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Coronavírus/genética , Receptores de Coronavírus/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença , Carga Viral , Replicação Viral , Soroterapia para COVID-19
20.
J Gen Virol ; 102(10)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34704922

RESUMO

Members of the family Herpesviridae have enveloped, spherical virions with characteristic complex structures consisting of symmetrical and non-symmetrical components. The linear, double-stranded DNA genomes of 125-241 kbp contain 70-170 genes, of which 43 have been inherited from an ancestral herpesvirus. In general, herpesviruses have coevolved with and are highly adapted to their hosts, which comprise many mammalian, avian and reptilian species. Following primary infection, they are able to establish lifelong latent infection, during which there is limited viral gene expression. Severe disease is usually observed only in the foetus, the very young, the immunocompromised or following infection of an alternative host. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Herpesviridae, which is available at ictv.global/report/herpesviridae.


Assuntos
Genoma Viral , Herpesviridae , Animais , Evolução Molecular , Herpesviridae/classificação , Herpesviridae/genética , Herpesviridae/fisiologia , Herpesviridae/ultraestrutura , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Adaptação ao Hospedeiro , Vírion/química , Vírion/ultraestrutura , Latência Viral , Replicação Viral
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