Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
EMBO J ; 42(14): e113168, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37248947

RESUMEN

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.


Asunto(s)
Venenos , Humanos , Proteínas y Péptidos de Choque por Frío/metabolismo , Frío , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
2.
Am J Pathol ; 194(7): 1374-1387, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38537932

RESUMEN

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.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Carcinoma de Células Renales , Proteínas de Ciclo Celular , Proliferación Celular , Neoplasias Renales , Mitocondrias , Receptores Tipo II del Factor de Necrosis Tumoral , Transducción de Señal , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Neoplasias Renales/genética , Mitocondrias/metabolismo , Fosfoproteínas/metabolismo , Fosforilación , Biosíntesis de Proteínas , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/genética
3.
Proc Biol Sci ; 291(2024): 20240435, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38835280

RESUMEN

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.


Asunto(s)
Agresión , Cognición , Conducta Social , Animales , Australia Occidental , Masculino , Passeriformes/fisiología , Femenino
4.
Anim Cogn ; 27(1): 52, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060612

RESUMEN

Despite considerable research into the structure of cognition in non-human animal species, there is still much debate as to whether animal cognition is organised as a series of discrete domains or an overarching general cognitive factor. In humans, the existence of general intelligence is widely accepted, but less work has been undertaken in animal psychometrics to address this question. The relatively few studies on non-primate animal species that do investigate the structure of cognition rarely include tasks assessing social cognition and focus instead on physical cognitive tasks. In this study, we tested 36 wild Western Australian magpies (Gymnorhina tibicen dorsalis) on a battery of three physical (associative learning, spatial memory, and numerical assessment) and one social (observational spatial memory) cognitive task, to investigate if cognition in this species fits a general cognitive factor model, or instead one of separate physical and social cognitive domains. A principal component analysis (PCA) identified two principal components with eigenvalues exceeding 1; a first component onto which all three physical tasks loaded strongly and positively, and a second component onto which only the social task (observational spatial memory) loaded strongly and positively. These findings provide tentative evidence for separate physical and social cognitive domains in this species, and highlight the importance of including tasks assessing both social and physical cognition in cognitive test batteries.


Asunto(s)
Cognición , Passeriformes , Animales , Masculino , Femenino , Passeriformes/fisiología , Memoria Espacial , Cognición Social
5.
Glob Chang Biol ; 29(24): 6912-6930, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37846601

RESUMEN

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.


Asunto(s)
Ecosistema , Passeriformes , Humanos , Animales , Australia , Ruido/efectos adversos , Animales Salvajes , Cognición
6.
Int J Cancer ; 138(8): 1959-70, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26619948

RESUMEN

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.


Asunto(s)
Anticuerpos Monoclonales , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/patología , Moléculas de Adhesión Celular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Secuencias de Aminoácidos , Animales , Especificidad de Anticuerpos , Sitios de Unión de Anticuerpos , Neoplasias de la Mama/metabolismo , Movimiento Celular/fisiología , Femenino , Humanos , Inmunohistoquímica , Ratones , Persona de Mediana Edad , Análisis de Matrices Tisulares
7.
Nat Genet ; 39(9): 1074-82, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17676041

RESUMEN

Genome-wide association studies are now identifying disease-associated chromosome regions. However, even after convincing replication, the localization of the causal variant(s) requires comprehensive resequencing, extensive genotyping and statistical analyses in large sample sets leading to targeted functional studies. Here, we have localized the type 1 diabetes (T1D) association in the interleukin 2 receptor alpha (IL2RA) gene region to two independent groups of SNPs, spanning overlapping regions of 14 and 40 kb, encompassing IL2RA intron 1 and the 5' regions of IL2RA and RBM17 (odds ratio = 2.04, 95% confidence interval = 1.70-2.45; P = 1.92 x 10(-28); control frequency = 0.635). Furthermore, we have associated IL2RA T1D susceptibility genotypes with lower circulating levels of the biomarker, soluble IL-2RA (P = 6.28 x 10(-28)), suggesting that an inherited lower immune responsiveness predisposes to T1D.


Asunto(s)
Mapeo Cromosómico/métodos , Diabetes Mellitus Tipo 1/genética , Subunidad alfa del Receptor de Interleucina-2/genética , Polimorfismo de Nucleótido Simple , Diabetes Mellitus Tipo 1/sangre , Salud de la Familia , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Subunidad alfa del Receptor de Interleucina-2/sangre , Desequilibrio de Ligamiento , Modelos Logísticos , Masculino , Oportunidad Relativa , Fenotipo
8.
Nat Genet ; 39(7): 857-64, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17554260

RESUMEN

The Wellcome Trust Case Control Consortium (WTCCC) primary genome-wide association (GWA) scan on seven diseases, including the multifactorial autoimmune disease type 1 diabetes (T1D), shows associations at P < 5 x 10(-7) between T1D and six chromosome regions: 12q24, 12q13, 16p13, 18p11, 12p13 and 4q27. Here, we attempted to validate these and six other top findings in 4,000 individuals with T1D, 5,000 controls and 2,997 family trios independent of the WTCCC study. We confirmed unequivocally the associations of 12q24, 12q13, 16p13 and 18p11 (P(follow-up)

Asunto(s)
Mapeo Cromosómico , Diabetes Mellitus Tipo 1/genética , Predisposición Genética a la Enfermedad , Genoma Humano , Adolescente , Estudios de Casos y Controles , Humanos , Polimorfismo de Nucleótido Simple
9.
Nat Genet ; 38(6): 617-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16699517

RESUMEN

In this study we report convincing statistical support for a sixth type 1 diabetes (T1D) locus in the innate immunity viral RNA receptor gene region IFIH1 (also known as mda-5 or Helicard) on chromosome 2q24.3. We found the association in an interim analysis of a genome-wide nonsynonymous SNP (nsSNP) scan, and we validated it in a case-control collection and replicated it in an independent family collection. In 4,253 cases, 5,842 controls and 2,134 parent-child trio genotypes, the risk ratio for the minor allele of the nsSNP rs1990760 A --> G (A946T) was 0.86 (95% confidence interval = 0.82-0.90) at P = 1.42 x 10(-10).


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Genoma Humano , Polimorfismo de Nucleótido Simple , ARN Helicasas/genética , Cromosomas Humanos Par 2 , ARN Helicasas DEAD-box , Genotipo , Humanos , Helicasa Inducida por Interferón IFIH1
10.
Development ; 138(6): 1131-42, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21307093

RESUMEN

In mammals, left-right (L-R) asymmetry is established by posteriorly oriented cilia driving a leftwards laminar flow in the embryonic node, thereby activating asymmetric gene expression. The two-cilia hypothesis argues that immotile cilia detect and respond to this flow through a Pkd2-mediated mechanism; a putative sensory partner protein has, however, remained unidentified. We have identified the Pkd1-related locus Pkd1l1 as a crucial component of L-R patterning in mouse. Systematic comparison of Pkd1l1 and Pkd2 point mutants reveals strong phenocopying, evidenced by both morphological and molecular markers of sidedness; both mutants fail to activate asymmetric gene expression at the node or in the lateral plate and exhibit right isomerism of the lungs. Node and cilia morphology were normal in mutants and cilia demonstrated typical motility, consistent with Pkd1l1 and Pkd2 activity downstream of nodal flow. Cell biological analysis reveals that Pkd1l1 and Pkd2 localise to the cilium and biochemical experiments demonstrate that they can physically interact. Together with co-expression in the node, these data argue that Pkd1l1 is the elusive Pkd2 binding partner required for L-R patterning and support the two-cilia hypothesis.


Asunto(s)
Tipificación del Cuerpo/genética , Proteínas de la Membrana/fisiología , Canales Catiónicos TRPP/metabolismo , Secuencia de Aminoácidos , Animales , Tipificación del Cuerpo/fisiología , Células Cultivadas , Cilios/genética , Cilios/metabolismo , Cilios/fisiología , Regulación del Desarrollo de la Expresión Génica , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Transgénicos , Modelos Biológicos , Modelos Moleculares , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple/genética , Polimorfismo de Nucleótido Simple/fisiología , Unión Proteica/genética , Unión Proteica/fisiología , Homología de Secuencia de Aminoácido , Canales Catiónicos TRPP/genética , Canales Catiónicos TRPP/fisiología
11.
Mol Reprod Dev ; 81(4): 284-314, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24273059

RESUMEN

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.


Asunto(s)
Citocinas/fisiología , Luteinización/fisiología , Oogénesis/fisiología , Folículo Ovárico/fisiología , Ovario/citología , Animales , Teorema de Bayes , Eosinófilos/metabolismo , Femenino , Líquido Folicular/química , Líquido Folicular/fisiología , Humanos , Subgrupos Linfocitarios/metabolismo , Mastocitos/metabolismo , Modelos Biológicos , Monocitos/metabolismo , Neutrófilos/metabolismo , Oocitos/crecimiento & desarrollo , Folículo Ovárico/ultraestructura , Ovario/metabolismo , Ovulación/fisiología , Embarazo , Índice de Embarazo , Técnicas Reproductivas Asistidas
12.
Autism ; 28(6): 1328-1343, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38197398

RESUMEN

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.


Asunto(s)
Antropología Cultural , Trastorno Autístico , Salud Mental , Humanos , Trastorno Autístico/psicología , Adaptación Psicológica
13.
Cell Death Dis ; 15(3): 203, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467609

RESUMEN

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.


Asunto(s)
Sistemas CRISPR-Cas , Membranas Asociadas a Mitocondrias , Sistemas CRISPR-Cas/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Calcio/metabolismo
14.
Nature ; 450(7171): 887-92, 2007 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-18004301

RESUMEN

The major histocompatibility complex (MHC) on chromosome 6 is associated with susceptibility to more common diseases than any other region of the human genome, including almost all disorders classified as autoimmune. In type 1 diabetes the major genetic susceptibility determinants have been mapped to the MHC class II genes HLA-DQB1 and HLA-DRB1 (refs 1-3), but these genes cannot completely explain the association between type 1 diabetes and the MHC region. Owing to the region's extreme gene density, the multiplicity of disease-associated alleles, strong associations between alleles, limited genotyping capability, and inadequate statistical approaches and sample sizes, which, and how many, loci within the MHC determine susceptibility remains unclear. Here, in several large type 1 diabetes data sets, we analyse a combined total of 1,729 polymorphisms, and apply statistical methods-recursive partitioning and regression-to pinpoint disease susceptibility to the MHC class I genes HLA-B and HLA-A (risk ratios >1.5; P(combined) = 2.01 x 10(-19) and 2.35 x 10(-13), respectively) in addition to the established associations of the MHC class II genes. Other loci with smaller and/or rarer effects might also be involved, but to find these, future searches must take into account both the HLA class II and class I genes and use even larger samples. Taken together with previous studies, we conclude that MHC-class-I-mediated events, principally involving HLA-B*39, contribute to the aetiology of type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Genes MHC Clase I/genética , Predisposición Genética a la Enfermedad/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Alelos , Estudios de Casos y Controles , Bases de Datos Genéticas , Frecuencia de los Genes , Genes MHC Clase II/genética , Genotipo , Antígenos HLA-DQ/genética , Cadenas beta de HLA-DQ , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Polimorfismo de Nucleótido Simple/genética , Tamaño de la Muestra , Población Blanca/genética
15.
Biochem J ; 441(2): 755-62, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22039967

RESUMEN

The production of cytotoxic nitric oxide (NO) and conversion into the neuropharmacological agent and potent greenhouse gas nitrous oxide (N2O) is linked with anoxic nitrate catabolism by Salmonella enterica serovar Typhimurium. Salmonella can synthesize two types of nitrate reductase: a membrane-bound form (Nar) and a periplasmic form (Nap). Nitrate catabolism was studied under nitrate-rich and nitrate-limited conditions in chemostat cultures following transition from oxic to anoxic conditions. Intracellular NO production was reported qualitatively by assessing transcription of the NO-regulated genes encoding flavohaemoglobin (Hmp), flavorubredoxin (NorV) and hybrid cluster protein (Hcp). A more quantitative analysis of the extent of NO formation was gained by measuring production of N2O, the end-product of anoxic NO-detoxification. Under nitrate-rich conditions, the nar, nap, hmp, norV and hcp genes were all induced following transition from the oxic to anoxic state, and 20% of nitrate consumed in steady-state was released as N2O when nitrite had accumulated to millimolar levels. The kinetics of nitrate consumption, nitrite accumulation and N2O production were similar to those of wild-type in nitrate-sufficient cultures of a nap mutant. In contrast, in a narG mutant, the steady-state rate of N2O production was ~30-fold lower than that of the wild-type. Under nitrate-limited conditions, nap, but not nar, was up-regulated following transition from oxic to anoxic metabolism and very little N2O production was observed. Thus a combination of nitrate-sufficiency, nitrite accumulation and an active Nar-type nitrate reductase leads to NO and thence N2O production, and this can account for up to 20% of the nitrate catabolized.


Asunto(s)
Membrana Celular/enzimología , Nitrato Reductasas/metabolismo , Nitrito Reductasas/metabolismo , Óxido Nitroso/metabolismo , Periplasma/enzimología , Salmonella typhimurium/enzimología , Aerobiosis , Anaerobiosis , Hipoxia de la Célula , Regulación Bacteriana de la Expresión Génica , Nitratos/metabolismo , Nitritos/metabolismo , Salmonella typhimurium/metabolismo
16.
J Eat Disord ; 11(1): 17, 2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36759874

RESUMEN

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.

17.
Sci Rep ; 13(1): 3934, 2023 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-36894612

RESUMEN

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.


Asunto(s)
Sistemas CRISPR-Cas , Retículo Endoplásmico , Humanos , Tunicamicina/farmacología , Retículo Endoplásmico/metabolismo , Muerte Celular , Estrés del Retículo Endoplásmico , Neuronas Dopaminérgicas/metabolismo , Apoptosis , Factores de Transcripción p300-CBP/metabolismo
18.
Biochim Biophys Acta ; 1807(4): 451-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21296048

RESUMEN

The active site of the bacterial nitric oxide reductase from Paracoccus denitrificans contains a dinuclear centre comprising heme b3 and non heme iron (Fe(B)). These metal centres are shown to be at isopotential with midpoint reduction potentials of E(m) ≈ +80 mV. The midpoint reduction potentials of the other two metal centres in the enzyme, heme c and heme b, are greater than the dinuclear centre suggesting that they act as an electron receiving/storage module. Reduction of the low-spin heme b causes structural changes at the dinuclear centre which allow access to substrate molecules. In the presence of the substrate analogue, CO, the midpoint reduction potential of heme b3 is raised to a region similar to that of heme c and heme b. This leads us to suggest that reduction of the electron transfer hemes leads to an opening of the active site which allows substrate to bind and in turn raises the reduction potential of the active site such that electrons are only delivered to the active site following substrate binding.


Asunto(s)
Dominio Catalítico , Hemo/química , Hemo/metabolismo , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Paracoccus denitrificans/enzimología , Transporte de Electrón , Concentración de Iones de Hidrógeno , Ligandos , Oxidación-Reducción
19.
J Allergy Clin Immunol ; 128(3): 549-56.e1-12, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21752437

RESUMEN

BACKGROUND: Asthma is a complex disease involving gene and environment interactions. Although atopy is a strong predisposing risk factor for asthma, local tissue susceptibilities are required for disease expression. The bronchial epithelium forms the interface with the external environment and is pivotally involved in controlling tissue homeostasis through provision of a physical barrier controlled by tight junction (TJ) complexes. OBJECTIVES: To explain the link between environment exposures and airway vulnerability, we hypothesized that epithelial TJs are abnormal in asthma, leading to increased susceptibility to environmental agents. METHODS: Localization of TJs in bronchial biopsies and differentiated epithelial cultures was assessed by electron microscopy or immunostaining. Baseline permeability and the effect of cigarette smoke and growth factor were assessed by measurement of transepithelial electrical resistance and passage of fluorescently labeled dextrans. RESULTS: By using immunostaining, we found that bronchial biopsies from asthmatic subjects displayed patchy disruption of TJs. In differentiated bronchial epithelial cultures, TJ formation and transepithelial electrical resistance were significantly lower (P < .05) in cultures from asthmatic donors (n = 43) than from normal controls (n = 40) and inversely correlated with macromolecular permeability. Cultures from asthmatic donors were also more sensitive to disruption by cigarette smoke extract. Epidermal growth factor enhanced basal TJ formation in cultures from asthmatic subjects (P < .01) and protected against cigarette smoke-induced barrier disruption (P < .01). CONCLUSIONS: Our results show that the bronchial epithelial barrier in asthma is compromised. This defect may facilitate the passage of allergens and other agents into the airway tissue, leading to immune activation and may thus contribute to the end organ expression of asthma.


Asunto(s)
Bronquios/patología , Células Epiteliales/patología , Uniones Estrechas/patología , Animales , Asma/patología , Biopsia , Bronquios/citología , Bronquios/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Células Cultivadas , Dextranos/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Células Epiteliales/metabolismo , Humanos , Ratones , Microscopía Electrónica , Fumar , Uniones Estrechas/metabolismo , Nicotiana
20.
Cell Rep Methods ; 2(11): 100341, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36452863

RESUMEN

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.


Asunto(s)
Dolor Crónico , Células Madre Pluripotentes Inducidas , Humanos , Nociceptores , Dolor Crónico/genética , Nocicepción , Células Receptoras Sensoriales/metabolismo , Canal de Sodio Activado por Voltaje NAV1.7/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA