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1.
Proc Biol Sci ; 291(2024): 20240435, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835280

RESUMO

Extensive research has investigated the relationship between the social environment and cognition, suggesting that social complexity may drive cognitive evolution and development. However, evidence for this relationship remains equivocal. Group size is often used as a measure of social complexity, but this may not capture intraspecific variation in social interactions. Social network analysis can provide insight into the cognitively demanding challenges associated with group living at the individual level. Here, we use social networks to investigate whether the cognitive performance of wild Western Australian magpies (Gymnorhina tibicen dorsalis) is related to group size and individual social connectedness. We quantified social connectedness using four interaction types: proximity, affiliative, agonistic and vocal. Consistent with previous research on this species, individuals in larger groups performed better on an associative learning task. However, social network position was also related to cognitive performance. Individuals receiving aggressive interactions performed better, while those involved in aggressive interactions with more group members performed worse. Overall, this suggests that cognitive performance is related to specific types of social interaction. The findings from this study highlight the value of considering fine-grained metrics of sociality that capture the challenges associated with social life when testing the relationship between the social environment and cognition.


Assuntos
Agressão , Cognição , Comportamento Social , Animais , Austrália Ocidental , Masculino , Passeriformes/fisiologia , Feminino
2.
Cell Death Dis ; 15(3): 203, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467609

RESUMO

Organelles form membrane contact sites between each other, allowing for the transfer of molecules and signals. Mitochondria-endoplasmic reticulum (ER) contact sites (MERCS) are cellular subdomains characterized by close apposition of mitochondria and ER membranes. They have been implicated in many diseases, including neurodegenerative, metabolic, and cardiac diseases. Although MERCS have been extensively studied, much remains to be explored. To uncover novel regulators of MERCS, we conducted a genome-wide, flow cytometry-based screen using an engineered MERCS reporter cell line. We found 410 genes whose downregulation promotes MERCS and 230 genes whose downregulation decreases MERCS. From these, 29 genes were selected from each population for arrayed screening and 25 were validated from the high population and 13 from the low population. GET4 and BAG6 were highlighted as the top 2 genes that upon suppression increased MERCS from both the pooled and arrayed screens, and these were subjected to further investigation. Multiple microscopy analyses confirmed that loss of GET4 or BAG6 increased MERCS. GET4 and BAG6 were also observed to interact with the known MERCS proteins, inositol 1,4,5-trisphosphate receptors (IP3R) and glucose-regulated protein 75 (GRP75). In addition, we found that loss of GET4 increased mitochondrial calcium uptake upon ER-Ca2+ release and mitochondrial respiration. Finally, we show that loss of GET4 rescues motor ability, improves lifespan and prevents neurodegeneration in a Drosophila model of Alzheimer's disease (Aß42Arc). Together, these results suggest that GET4 is involved in decreasing MERCS and that its loss is neuroprotective.


Assuntos
Sistemas CRISPR-Cas , Membranas Associadas à Mitocôndria , Sistemas CRISPR-Cas/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Cálcio/metabolismo
3.
Am J Pathol ; 194(7): 1374-1387, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38537932

RESUMO

Clear-cell renal cell carcinoma (ccRCC), a tubular epithelial malignancy, secretes tumor necrosis factor (TNF), which signals ccRCC cells in an autocrine manner via two cell surface receptors, TNFR1 and TNFR2, to activate shared and distinct signaling pathways. Selective ligation of TNFR2 drives cell cycle entry of malignant cells via a signaling pathway involving epithelial tyrosine kinase, vascular endothelial cell growth factor receptor type 2, phosphatidylinositol-3-kinase, Akt, pSer727-Stat3, and mammalian target of rapamycin. In this study, phosphorylated 4E binding protein-1 (4EBP1) serine 65 (pSer65-4EBP1) was identified as a downstream target of this TNFR2 signaling pathway. pSer65-4EBP1 expression was significantly elevated relative to total 4EBP1 in ccRCC tissue compared with that in normal kidneys, with signal intensity increasing with malignant grade. Selective ligation of TNFR2 with the TNFR2-specific mutein increased pSer65-4EBP1 expression in organ cultures that co-localized with internalized TNFR2 in mitochondria and increased expression of mitochondrially encoded COX (cytochrome c oxidase subunit) Cox1, as well as nuclear-encoded Cox4/5b subunits. Pharmacologic inhibition of mammalian target of rapamycin reduced both TNFR2-specific mutein-mediated phosphorylation of 4EBP1 and cell cycle activation in tumor cells while increasing cell death. These results signify the importance of pSer65-4EBP1 in mediating TNFR2-driven cell-cycle entry in tumor cells in ccRCC and implicate a novel relationship between the TNFR2/pSer65-4EBP1/COX axis and mitochondrial function.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Carcinoma de Células Renais , Proteínas de Ciclo Celular , Proliferação de Células , Neoplasias Renais , Mitocôndrias , Receptores Tipo II do Fator de Necrose Tumoral , Transdução de Sinais , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Neoplasias Renais/genética , Mitocôndrias/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Biossíntese de Proteínas , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/genética
4.
Autism ; 28(6): 1328-1343, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38197398

RESUMO

LAY ABSTRACT: Some autistic people describe trying to hide autistic behaviour and seem more neurotypical. Researchers called this 'social camouflaging' and have linked it with mental health difficulties. We used a step-by-step approach to identify research where autistic people talk about social camouflaging to explore the relationship between camouflaging and poor mental health. Thirteen studies were combined. The results describe how society negatively impacts autistic people's mental health, and camouflaging is a way to try and cope with this. Many autistic people find their camouflaging strategies have accidental negative consequences which also affect their mental health. Strategies which seemed 'successful' involved a lot of self-monitoring, were very mentally demanding or were very habitual and seemed to have more of an effect on mental health. This might be important for clinicians who support autistic people with mental health difficulties.


Assuntos
Antropologia Cultural , Transtorno Autístico , Saúde Mental , Humanos , Transtorno Autístico/psicologia , Adaptação Psicológica
5.
Glob Chang Biol ; 29(24): 6912-6930, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37846601

RESUMO

Anthropogenic noise is a pollutant of growing concern, with wide-ranging effects on taxa across ecosystems. Until recently, studies investigating the effects of anthropogenic noise on animals focused primarily on population-level consequences, rather than individual-level impacts. Individual variation in response to anthropogenic noise may result from extrinsic or intrinsic factors. One such intrinsic factor, cognitive performance, varies between individuals and is hypothesised to aid behavioural response to novel stressors. Here, we combine cognitive testing, behavioural focals and playback experiments to investigate how anthropogenic noise affects the behaviour and anti-predator response of Western Australian magpies (Gymnorhina tibicen dorsalis), and to determine whether this response is linked to cognitive performance. We found a significant population-level effect of anthropogenic noise on the foraging effort, foraging efficiency, vigilance, vocalisation rate and anti-predator response of magpies, with birds decreasing their foraging, vocalisation behaviours and anti-predator response, and increasing vigilance when loud anthropogenic noise was present. We also found that individuals varied in their response to playbacks depending on their cognitive performance, with individuals that performed better in an associative learning task maintaining their anti-predator response when an alarm call was played in anthropogenic noise. Our results add to the growing body of literature documenting the adverse effects of anthropogenic noise on wildlife and provide the first evidence for an association between individual cognitive performance and behavioural responses to anthropogenic noise.


Assuntos
Ecossistema , Passeriformes , Humanos , Animais , Austrália , Ruído/efeitos adversos , Animais Selvagens , Cognição
6.
EMBO J ; 42(14): e113168, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37248947

RESUMO

Enhanced expression of the cold-shock protein RNA binding motif 3 (RBM3) is highly neuroprotective both in vitro and in vivo. Whilst upstream signalling pathways leading to RBM3 expression have been described, the precise molecular mechanism of RBM3 cold induction remains elusive. To identify temperature-dependent modulators of RBM3, we performed a genome-wide CRISPR-Cas9 knockout screen using RBM3-reporter human iPSC-derived neurons. We found that RBM3 mRNA and protein levels are robustly regulated by several splicing factors, with heterogeneous nuclear ribonucleoprotein H1 (HNRNPH1) being the strongest positive regulator. Splicing analysis revealed that moderate hypothermia significantly represses the inclusion of a poison exon, which, when retained, targets the mRNA for nonsense-mediated decay. Importantly, we show that HNRNPH1 mediates this cold-dependent exon skipping via its thermosensitive interaction with a G-rich motif within the poison exon. Our study provides novel mechanistic insights into the regulation of RBM3 and provides further targets for neuroprotective therapeutic strategies.


Assuntos
Venenos , Humanos , Proteínas e Peptídeos de Choque Frio/metabolismo , Temperatura Baixa , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Sci Rep ; 13(1): 3934, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894612

RESUMO

Accumulation of aggregated and misfolded proteins, leading to endoplasmic reticulum stress and activation of the unfolded protein response, is a hallmark of several neurodegenerative disorders, including Alzheimer's and Parkinson's disease. Genetic screens are powerful tools that are proving invaluable in identifying novel modulators of disease associated processes. Here, we performed a loss-of-function genetic screen using a human druggable genome library, followed by an arrayed-screen validation, in human iPSC-derived cortical neurons. We identified and genetically validated 13 genes, whose knockout was neuroprotective against Tunicamycin, a glycoprotein synthesis inhibitor widely used to induce endoplasmic reticulum stress. We also demonstrated that pharmacological inhibition of KAT2B, a lysine acetyltransferase identified by our genetic screens, by L-Moses, attenuates Tunicamycin-mediated neuronal cell death and activation of CHOP, a key pro-apoptotic member of the unfolded protein response in both cortical and dopaminergic neurons. Follow-up transcriptional analysis suggested that L-Moses provided neuroprotection by partly reversing the transcriptional changes caused by Tunicamycin. Finally, L-Moses treatment attenuated total protein levels affected by Tunicamycin, without affecting their acetylation profile. In summary, using an unbiased approach, we identified KAT2B and its inhibitor, L-Moses, as potential therapeutic targets for neurodegenerative diseases.


Assuntos
Sistemas CRISPR-Cas , Retículo Endoplasmático , Humanos , Tunicamicina/farmacologia , Retículo Endoplasmático/metabolismo , Morte Celular , Estresse do Retículo Endoplasmático , Neurônios Dopaminérgicos/metabolismo , Apoptose , Fatores de Transcrição de p300-CBP/metabolismo
8.
J Eat Disord ; 11(1): 17, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759874

RESUMO

BACKGROUND: There is an increased prevalence of anorexia nervosa (AN) in autistic women and this group has poorer treatment outcomes compared to non-autistic women with AN. However, there is little research into improving eating disorder treatment for autistic women. This study investigated how best to support autistic women with AN within eating disorder services. METHOD: A three-stage Delphi study was conducted with 49 participants with relevant expertise as a researcher, clinician, or expert by experience. RESULTS: A total of 70 statements were generated, with 56 reaching consensus after the final round. Statements reaching consensus made recommendations for adaptations to treatment, staff training, and service organisation. CONCLUSIONS: The results highlight the need to distinguish between autism- and AN-related difficulties, accommodate autistic traits such as sensory sensitivities and communication differences, and ensure the autistic voice is present in both the development and delivery of care. Future research should investigate the impact of these adaptations on outcomes. The applicability of these recommendations to autistic people with other eating disorders and of other genders needs to be investigated further.


Autistic women are more likely to have anorexia nervosa (AN) than non-autistic women. Autistic women can find eating disorder treatment unhelpful and need adaptations to treatment. This study asked a group of 49 researchers, staff, and people with personal experience of autism and eating disorders what they thought would help autistic women with AN. The study used a Delphi study method, which allows the calculation of how much participants agree without them needing to meet and make a decision. The study created 56 suggestions that the participants agreed on. The results give suggestions for changing treatment, training staff, and changing how services work to be better for autistic women. The suggestions highlight the importance of being able to tell the difference between autism- and AN- related behaviour, adjusting care to accommodate autistic traits, and involving autistic people in the development of care. Many of the suggestions recommend that changes are flexible to the individual autistic person. In the future, research should check if these changes are helpful for autistic women with AN, and if they would be helpful for autistic people who are not female or have other eating disorders.

9.
Cell Rep Methods ; 2(11): 100341, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36452863

RESUMO

Despite development of protocols to differentiate human pluripotent stem cells (hPSCs), those used to produce sensory neurons remain difficult to replicate and result in heterogenous populations. There is a growing clinical burden of chronic pain conditions, highlighting the need for relevant human cellular models. This study presents a hybrid differentiation method to produce nociceptive sensory neurons from hPSCs. Lines harboring an inducible NEUROG2 construct were patterned toward precursors with small molecules followed by NEUROG2 overexpression. Neurons expressed key markers, including BRN3A and ISL1, with single-cell RNA sequencing, revealing populations of nociceptors expressing SCN9A and TRP channels. Physiological profiling with multi-electrode arrays revealed that neurons responded to noxious stimuli, including capsaicin. Finally, we modeled pain-like states to identify genes and pathways involved in pain transduction. This study presents an optimized method to efficiently produce nociceptive sensory neurons and provides a tool to aid development of chronic pain research.


Assuntos
Dor Crônica , Células-Tronco Pluripotentes Induzidas , Humanos , Nociceptores , Dor Crônica/genética , Nociceptividade , Células Receptoras Sensoriais/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
10.
Cell Rep ; 37(12): 110132, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34936871

RESUMO

The prostate gland produces prostatic fluid, high in zinc and citrate and essential for the maintenance of spermatozoa. Prostate cancer is a common condition with limited treatment efficacy in castration-resistant metastatic disease, including with immune checkpoint inhibitors. Using single-cell RNA-sequencing to perform an unbiased assessment of the cellular landscape of human prostate, we identify a subset of tumor-enriched androgen receptor-negative luminal epithelial cells with increased expression of cancer-associated genes. We also find a variety of innate and adaptive immune cells in normal prostate that were transcriptionally perturbed in prostate cancer. An exception is a prostate-specific, zinc transporter-expressing macrophage population (MAC-MT) that contributes to tissue zinc accumulation in homeostasis but shows enhanced inflammatory gene expression in tumors, including T cell-recruiting chemokines. Remarkably, enrichment of the MAC-MT signature in cancer biopsies is associated with improved disease-free survival, suggesting beneficial antitumor functions.


Assuntos
Células Epiteliais/metabolismo , Macrófagos/metabolismo , Próstata/imunologia , Próstata/metabolismo , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Transcriptoma , Idoso , Animais , Células Epiteliais/imunologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , RNA-Seq , Receptores Androgênicos/metabolismo , Análise de Célula Única/métodos , Zinco/metabolismo
11.
iScience ; 23(11): 101703, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33196026

RESUMO

Advances in single cell genomics and transcriptomics have shown that at tissue level there is complex cellular heterogeneity. To understand the effect of this inter-cell heterogeneity on metabolism it is essential to develop a single cell lipid profiling approach that allows the measurement of lipids in large numbers of single cells from a population. This will provide a functional readout of cell activity and membrane structure. Using liquid extraction surface analysis coupled with high-resolution mass spectrometry we have developed a high-throughput method for untargeted single cell lipid profiling. This technological advance highlighted the importance of cellular heterogeneity in the functional metabolism of individual human dopamine neurons, suggesting that A53T alpha-synuclein (SNCA) mutant neurons have impaired membrane function. These results demonstrate that this single cell lipid profiling platform can provide robust data that will expand the frontiers in biomedical research.

12.
Cell Rep ; 33(2): 108263, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33053338

RESUMO

The advent of induced pluripotent stem cell (iPSC)-derived neurons has revolutionized Parkinson's disease (PD) research, but single-cell transcriptomic analysis suggests unresolved cellular heterogeneity within these models. Here, we perform the largest single-cell transcriptomic study of human iPSC-derived dopaminergic neurons to elucidate gene expression dynamics in response to cytotoxic and genetic stressors. We identify multiple neuronal subtypes with transcriptionally distinct profiles and differential sensitivity to stress, highlighting cellular heterogeneity in dopamine in vitro models. We validate this disease model by showing robust expression of PD GWAS genes and overlap with postmortem adult substantia nigra neurons. Importantly, stress signatures are ameliorated using felodipine, an FDA-approved drug. Using isogenic SNCA-A53T mutants, we find perturbations in glycolysis, cholesterol metabolism, synaptic signaling, and ubiquitin-proteasomal degradation. Overall, our study reveals cell type-specific perturbations in human dopamine neurons, which will further our understanding of PD and have implications for cell replacement therapies.


Assuntos
Neurônios Dopaminérgicos/patologia , Modelos Biológicos , Doença de Parkinson/genética , Doença de Parkinson/patologia , Análise de Célula Única , Estresse Fisiológico , Transcriptoma/genética , Diferenciação Celular/genética , Respiração Celular , Colesterol/metabolismo , Montagem e Desmontagem da Cromatina , Neurônios Dopaminérgicos/metabolismo , Regulação para Baixo/genética , Estresse do Retículo Endoplasmático/genética , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Glicólise/genética , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Fosforilação Oxidativa , Estresse Oxidativo/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Análise de Regressão , Transdução de Sinais , Estresse Fisiológico/genética , Sinapses/metabolismo , Ubiquitina/metabolismo , Regulação para Cima/genética
13.
PLoS One ; 12(11): e0188897, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29190674

RESUMO

It has long been established that active agents in seminal fluid are key to initiating and coordinating mating-induced immunomodulation. This is in part governed by the actions of a network of cytokine interactions which, to date, remain largely undefined, and whose interspecific evolutionary conservation is unknown. This study applied Bayesian methods to illustrate the interrelationships between seminal profiles of interleukin (IL)-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12 (p70), IL-13, IL-17, eotaxin, granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage-colony stimulating factor (GM-CSF), interferon (IFN)-gamma, keratinocyte-derived chemokine (KC), monocyte chemoattractant protein (MCP-1), macrophage inflammatory protein (MIP-1) alpha, MIP-1beta, regulated on activation normal T cell expressed and secreted (RANTES), tumour necrosis factor (TNF)-alpha, leptin, inducible protein (IP)-10 and vascular endothelial growth factor (VEGF) in a rat model. IL-2, IL-9, IL-12 (p70), IL-13, IL-18, eotaxin, IFN-gamma, IP-10, KC, leptin, MCP-1, MIP-1alpha and TNF-alpha were significantly higher in serum, whilst IL-1beta, IL-5, IL-6, IL-10, IL-17, G-CSF and GM-CSF were significantly higher in seminal fluid. When compared to mouse profiles, only G-CSF was present at significantly higher levels in the seminal fluid in both species. Bayesian modelling highlighted key shared features across mouse and rat networks, namely TNF-alpha as the terminal node in both serum and seminal plasma, and MCP-1 as a central coordinator of seminal cytokine networks through the intermediary of KC and RANTES. These findings reveal a marked interspecific conservation of seminal cytokine networks.


Assuntos
Teorema de Bayes , Citocinas/metabolismo , Sêmen/metabolismo , Animais , Masculino , Ratos , Ratos Wistar
14.
NPJ Genom Med ; 2: 6, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263824

RESUMO

Aberrant genetic and epigenetic variations drive malignant transformation and are hallmarks of cancer. Using PCR-free sample preparation we achieved the first in-depth whole genome (hydroxyl)-methylcytosine, single-base-resolution maps from a glioblastoma tumour/margin sample of a patient. Our data provide new insights into how genetic and epigenetic variations are interrelated. In the tumour, global hypermethylation with a depletion of 5-hydroxymethylcytosine was observed. The majority of single nucleotide variations were identified as cytosine-to-thymine deamination products within CpG context, where cytosine was preferentially methylated in the margin. Notably, we observe that cells neighbouring tumour cells display epigenetic alterations characteristic of the tumour itself although genetically they appear "normal". This shows the potential transfer of epigenetic information between cells that contributes to the intratumour heterogeneity of glioblastoma. Together, our reference (epi)-genome provides a human model system for future studies that aim to explore the link between genetic and epigenetic variations in cancer progression.

15.
Int J Cancer ; 138(8): 1959-70, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26619948

RESUMO

Periostin (POSTN), a secreted homodimeric protein that binds integrins αvß3, αvß5, and α6ß4, was originally found to be expressed in fetal tissues and in the adult upon injury particularly bone fractures due to its role in remodelling and repair. Recently it was found to be over-expressed in human breast cancer and a variety of other tumour types including head and neck squamous cell carcinoma, where its overexpression correlates with increased tumour invasion. Progress in studying its functional role in tumour pathogenesis has been hampered by the paucity of antibodies for its specific and sensitive detection. It has proven very difficult to obtain monoclonal antibodies (mAbs) against this highly conserved protein but we report here that combining infection of mice with lactate dehydrogenase elevating virus (LDV), a B cell activating arterivirus, with conjugation of human POSTN to ovalbumin as an immunogenic carrier, enabled us to develop six mAbs recognizing both human and mouse POSTN and inhibiting its binding to αvß3 integrin. Two of the mAbs, MPB4B1 and MPC5B4, were tested and found to inhibit POSTN-induced migration of human endothelial colony forming cells. All six mAbs recognized amino acids 136-51 (APSNEAWDNLDSDIRR) within the POSTN fascilin (FAS) 1-1 domain revealing the functional importance of this motif; this was further highlighted by the ability of aa 136-151 peptide to inhibit integrin-mediated cell migration. Immunohistochemistry using MPC5B4, indicated that breast tumour cell POSTN expression was a strong prognostic indicator, along with tumour size, lymph node, and human epidermal growth factor receptor 2 (HER2) status.


Assuntos
Anticorpos Monoclonais , Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Moléculas de Adesão Celular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Motivos de Aminoácidos , Animais , Especificidade de Anticorpos , Sítios de Ligação de Anticorpos , Neoplasias da Mama/metabolismo , Movimento Celular/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Camundongos , Pessoa de Meia-Idade , Análise Serial de Tecidos
16.
BMC Syst Biol ; 9: 76, 2015 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-26553024

RESUMO

BACKGROUND: Cytokine-hormone network deregulations underpin pathologies ranging from autoimmune disorders to cancer, but our understanding of these networks in physiological/pathophysiological states remains patchy. We employed Bayesian networks to analyze cytokine-hormone interactions in vivo using murine lactation as a dynamic, physiological model system. RESULTS: Circulatory levels of estrogen, progesterone, prolactin and twenty-three cytokines were profiled in post partum mice with/without pups. The resultant networks were very robust and assembled about structural hubs, with evidence that interleukin (IL)-12 (p40), IL-13 and monocyte chemoattractant protein (MCP)-1 were the primary drivers of network behavior. Network structural conservation across physiological scenarios coupled with the successful empirical validation of our approach suggested that in silico network perturbations can predict in vivo qualitative responses. In silico perturbation of network components also captured biological features of cytokine interactions (antagonism, synergy, redundancy). CONCLUSION: These findings highlight the potential of network-based approaches in identifying novel cytokine pharmacological targets and in predicting the effects of their exogenous manipulation in inflammatory/immune disorders.


Assuntos
Quimiocina CCL2/metabolismo , Citocinas/metabolismo , Interleucina-12/metabolismo , Interleucina-13/metabolismo , Modelos Biológicos , Animais , Teorema de Bayes , Feminino , Hormônios/sangue , Lactação/fisiologia , Camundongos , Período Pós-Parto , Mapas de Interação de Proteínas
17.
Biotechnol Biofuels ; 8: 33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25861389

RESUMO

BACKGROUND: Fermentation of bioethanol using lignocellulosic biomass as a raw material provides a sustainable alternative to current biofuel production methods by utilising waste food streams as raw material. Before lignocellulose can be fermented, it requires physical, chemical and enzymatic treatment in order to release monosaccharides, a process that causes the chemical transformation of glucose and xylose into the cyclic aldehydes furfural and hydroxyfurfural. These furan compounds are potent inhibitors of Saccharomyces fermentation, and consequently furfural tolerant strains of Saccharomyces are required for lignocellulosic fermentation. RESULTS: This study investigated yeast tolerance to furfural and hydroxyfurfural using a collection of 71 environmental and industrial isolates of the baker's yeast Saccharomyces cerevisiae and its closest relative Saccharomyces paradoxus. The Saccharomyces strains were initially screened for growth on media containing 100 mM glucose and 1.5 mg ml(-1) furfural. Five strains were identified that showed a significant tolerance to growth in the presence of furfural, and these were then screened for growth and ethanol production in the presence of increasing amounts (0.1 to 4 mg ml(-1)) of furfural. CONCLUSIONS: Of the five furfural tolerant strains, S. cerevisiae National Collection of Yeast Cultures (NCYC) 3451 displayed the greatest furfural resistance and was able to grow in the presence of up to 3.0 mg ml(-1) furfural. Furthermore, ethanol production in this strain did not appear to be inhibited by furfural, with the highest ethanol yield observed at 3.0 mg ml(-1) furfural. Although furfural resistance was not found to be a trait specific to any one particular lineage or population, three of the strains were isolated from environments where they might be continually exposed to low levels of furfural through the ongoing natural degradation of lignocelluloses, and would therefore develop elevated levels of resistance to these furan compounds. Thus, these strains represent good candidates for future studies of genetic variation relevant to understanding and manipulating furfural resistance and in the development of tolerant ethanologenic yeast strains for use in bioethanol production from lignocellulose processing.

18.
PLoS One ; 10(2): e0118202, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706862

RESUMO

The Infinium 450K Methylation array is an established tool for measuring methylation. However, the bisulfite (BS) reaction commonly used with the 450K array cannot distinguish between 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). The oxidative-bisulfite assay disambiguates 5mC and 5hmC. We describe the use of oxBS in conjunction with the 450K array (oxBS-array) to analyse 5hmC/5mC in cerebellum DNA. The "methylation" level derived by the BS reaction is the combined level of 5mC and 5hmC at a given base, while the oxBS reaction gives the level of 5mC alone. The level of 5hmC is derived by subtracting the oxBS level from the BS level. Here we present an analysis method that distinguishes genuine positive levels of 5hmC at levels as low as 3%. We performed four replicates of the same sample of cerebellum and found a high level of reproducibility (average r for BS = 98.3, and average r for oxBS = 96.8). In total, 114,734 probes showed a significant positive measurement for 5hmC. The range at which we were able to distinguish 5hmC occupancy was between 3% and 42%. In order to investigate the effects of multiple replicates on 5hmC detection we also simulated fewer replicates and found that decreasing the number of replicates to two reduced the number of positive probes identified by > 50%. We validated our results using qPCR in conjunction with glucosylation of 5hmC sites followed by MspI digestion and we found good concordance with the array estimates (r = 0.94). This experiment provides a map of 5hmC in the cerebellum and a robust dataset for use as a standard in future 5hmC analyses. We also provide a novel method for validating the presence of 5hmC at low levels, and highlight some of the pitfalls associated with measuring 5hmC and 5mC.


Assuntos
5-Metilcitosina/metabolismo , Cerebelo/metabolismo , Citosina/análogos & derivados , DNA/metabolismo , Sulfitos/metabolismo , Adulto , Citosina/metabolismo , Metilação de DNA/fisiologia , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Oxirredução , Reprodutibilidade dos Testes
19.
Nat Genet ; 46(5): 492-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24686848

RESUMO

Common multi-allelic copy number variants (CNVs) appear enriched for phenotypic associations compared to their biallelic counterparts. Here we investigated the influence of gene dosage effects on adiposity through a CNV association study of gene expression levels in adipose tissue. We identified significant association of a multi-allelic CNV encompassing the salivary amylase gene (AMY1) with body mass index (BMI) and obesity, and we replicated this finding in 6,200 subjects. Increased AMY1 copy number was positively associated with both amylase gene expression (P = 2.31 × 10(-14)) and serum enzyme levels (P < 2.20 × 10(-16)), whereas reduced AMY1 copy number was associated with increased BMI (change in BMI per estimated copy = -0.15 (0.02) kg/m(2); P = 6.93 × 10(-10)) and obesity risk (odds ratio (OR) per estimated copy = 1.19, 95% confidence interval (CI) = 1.13-1.26; P = 1.46 × 10(-10)). The OR value of 1.19 per copy of AMY1 translates into about an eightfold difference in risk of obesity between subjects in the top (copy number > 9) and bottom (copy number < 4) 10% of the copy number distribution. Our study provides a first genetic link between carbohydrate metabolism and BMI and demonstrates the power of integrated genomic approaches beyond genome-wide association studies.


Assuntos
Metabolismo dos Carboidratos/genética , Dosagem de Genes/genética , Predisposição Genética para Doença/genética , Obesidade/genética , alfa-Amilases Salivares/genética , Índice de Massa Corporal , Genômica/métodos , Humanos , Análise em Microsséries , Razão de Chances , alfa-Amilases Salivares/sangue
20.
Mol Reprod Dev ; 81(4): 284-314, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24273059

RESUMO

Cytokines are key regulators of ovarian physiology, particularly in relation to folliculogenesis and ovulation, where they contribute to creating an environment supporting follicle selection and growth. Their manifold functions include regulating cellular proliferation/differentiation, follicular survival/atresia, and oocyte maturation. Several cytokines, such as TGF-ß-superfamily members, are involved at all stages of folliculogenesis while the production of others is stage-dependent. This review draws upon evidence from both human and animal models to highlight the species-specific roles at each milestone of follicular development. Given these pivotal roles and their ease of detection in follicular fluid, cytokines have been considered as attractive biomarkers of oocyte maturational status and of successful assisted reproductive outcome. Despite this, our understanding of cytokines and their interactions remains incomplete, and is still frequently limited to overly simplistic descriptions of their interrelationships. Given our increased appreciation of cytokine activity in complex and highly regulated networks, we put forward the case for using Bayesian modelling approaches to describe their hierarchical relationships in order to predict causal physiological interactions in vivo.


Assuntos
Citocinas/fisiologia , Luteinização/fisiologia , Oogênese/fisiologia , Folículo Ovariano/fisiologia , Ovário/citologia , Animais , Teorema de Bayes , Eosinófilos/metabolismo , Feminino , Líquido Folicular/química , Líquido Folicular/fisiologia , Humanos , Subpopulações de Linfócitos/metabolismo , Mastócitos/metabolismo , Modelos Biológicos , Monócitos/metabolismo , Neutrófilos/metabolismo , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/ultraestrutura , Ovário/metabolismo , Ovulação/fisiologia , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida
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