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1.
Nat Commun ; 15(1): 9415, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39482307

RESUMO

Intrinsically disordered regions (IDRs) are highly enriched in the nucleolar proteome but their physiological role in ribosome assembly remains poorly understood. Our study reveals the functional plasticity of the extremely abundant lysine-rich IDRs of small nucleolar ribonucleoprotein particles (snoRNPs) from protists to mammalian cells. We show in Saccharomyces cerevisiae that the electrostatic properties of this lysine-rich IDR, the KKE/D domain, promote snoRNP accumulation in the vicinity of nascent rRNAs, facilitating their modification. Under stress conditions reducing the rate of ribosome assembly, they are essential for nucleolar compaction and sequestration of key early-acting ribosome biogenesis factors, including RNA polymerase I, owing to their self-interaction capacity in a latent, non-rRNA-associated state. We propose that such functional plasticity of these lysine-rich IDRs may represent an ancestral eukaryotic regulatory mechanism, explaining how nucleolar morphology is continuously adapted to rRNA production levels.


Assuntos
Nucléolo Celular , Lisina , RNA Ribossômico , Ribonucleoproteínas Nucleolares Pequenas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Lisina/metabolismo , Lisina/química , Nucléolo Celular/metabolismo , RNA Ribossômico/metabolismo , RNA Ribossômico/química , RNA Ribossômico/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Ribonucleoproteínas Nucleolares Pequenas/metabolismo , Ribonucleoproteínas Nucleolares Pequenas/genética , Ribossomos/metabolismo , Domínios Proteicos , RNA Polimerase I/metabolismo , RNA Polimerase I/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/genética , Humanos
2.
Nutrients ; 16(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999805

RESUMO

We previously reported that a combined myo-inositol, probiotics, and enriched micronutrient supplement (intervention) taken preconception and in pregnancy reduced postpartum blood loss (PBL) and major postpartum hemorrhage compared with a standard micronutrient supplement (control), as secondary outcomes of the NiPPeR trial. This study aimed to identify the intervention components that may contribute to this effect. Associations of plasma concentrations of myo-inositol and vitamins B2, B6, B12, and D at preconception (before and after supplementation), early (~7-weeks), and late pregnancy (~28-weeks) with PBL were assessed by multiple linear regression, adjusting for site, ethnicity, preconception BMI, parity, and previous cesarean section. Amongst 583 women, a higher concentration of myo-inositol in early pregnancy was associated with a PBL reduction [ßadj -1.26 (95%CI -2.23, -0.29) mL per µmol/L myo-inositol increase, p = 0.011]. Applying this co-efficient to the increase in mean 7-week-myo-inositol concentration of 23.4 µmol/L with the intervention equated to a PBL reduction of 29.5 mL (~8.4% of mean PBL of 350 mL among controls), accounting for 84.3% of the previously reported intervention effect of 35 mL. None of the examined vitamins were associated with PBL. Therefore, myo-inositol may be a key intervention component mediating the PBL reduction. Further work is required to determine the mechanisms involved.


Assuntos
Suplementos Nutricionais , Inositol , Hemorragia Pós-Parto , Humanos , Feminino , Inositol/sangue , Inositol/administração & dosagem , Gravidez , Adulto , Hemorragia Pós-Parto/sangue , Hemorragia Pós-Parto/prevenção & controle , Micronutrientes/sangue , Fenômenos Fisiológicos da Nutrição Materna , Período Pós-Parto/sangue
3.
Mol Cell ; 84(12): 2337-2352.e9, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38870935

RESUMO

Ribosome assembly requires precise coordination between the production and assembly of ribosomal components. Mutations in ribosomal proteins that inhibit the assembly process or ribosome function are often associated with ribosomopathies, some of which are linked to defects in proteostasis. In this study, we examine the interplay between several yeast proteostasis enzymes, including deubiquitylases (DUBs) Ubp2 and Ubp14, and E3 ligases Ufd4 and Hul5, and we explore their roles in the regulation of the cellular levels of K29-linked unanchored polyubiquitin (polyUb) chains. Accumulating K29-linked unanchored polyUb chains associate with maturing ribosomes to disrupt their assembly, activate the ribosome assembly stress response (RASTR), and lead to the sequestration of ribosomal proteins at the intranuclear quality control compartment (INQ). These findings reveal the physiological relevance of INQ and provide insights into mechanisms of cellular toxicity associated with ribosomopathies.


Assuntos
Poliubiquitina , Proteínas Ribossômicas , Ribossomos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/genética , Ribossomos/metabolismo , Ribossomos/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Poliubiquitina/metabolismo , Poliubiquitina/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Proteostase , Núcleo Celular/metabolismo
4.
Plants (Basel) ; 13(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611498

RESUMO

In the context of climate change and the reduction of mineral nitrogen (N) inputs applied to the field, winter oilseed rape (WOSR) will have to cope with low-N conditions combined with water limitation periods. Since these stresses can significantly reduce seed yield and seed quality, maintaining WOSR productivity under a wide range of growth conditions represents a major goal for crop improvement. N metabolism plays a pivotal role during the metabolic acclimation to drought in Brassica species by supporting the accumulation of osmoprotective compounds and the source-to-sink remobilization of nutrients. Thus, N deficiency could have detrimental effects on the acclimation of WOSR to drought. Here, we took advantage of a previously established experiment to evaluate the metabolic acclimation of WOSR during 14 days of drought, followed by 8 days of rehydration under high- or low-N fertilization regimes. For this purpose, we selected three leaf ranks exhibiting contrasted sink/source status to perform absolute quantification of plant central metabolites. Besides the well-described accumulation of proline, we observed contrasted accumulations of some "respiratory" amino acids (branched-chain amino acids, lysineand tyrosine) in response to drought under high- and low-N conditions. Drought also induced an increase in sucrose content in sink leaves combined with a decrease in source leaves. N deficiency strongly decreased the levels of major amino acids and subsequently the metabolic response to drought. The drought-rehydration sequence identified proline, phenylalanine, and tryptophan as valuable metabolic indicators of WOSR water status for sink leaves. The results were discussed with respect to the metabolic origin of sucrose and some amino acids in sink leaves and the impact of drought on source-to-sink remobilization processes depending on N nutrition status. Overall, this study identified major metabolic signatures reflecting a similar response of oilseed rape to drought under low- and high-N conditions.

5.
BMJ Open ; 14(2): e074625, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320845

RESUMO

INTRODUCTION: Autism (formally autism spectrum disorder) encompasses a group of complex neurodevelopmental conditions, characterised by differences in communication and social interactions. Co-occurring chronic gastrointestinal symptoms are common among autistic individuals and can adversely affect their quality of life. This study aims to evaluate the efficacy of oral encapsulated faecal microbiome transfer (FMT) in improving gastrointestinal symptoms and well-being among autistic adolescents and adults. METHODS AND ANALYSIS: This double-blind, randomised, placebo-controlled trial will recruit 100 autistic adolescents and adults aged 16-45 years, who have mild to severe gastrointestinal symptoms (Gastrointestinal Symptoms Rating Scale (GSRS) score ≥2.0). We will also recruit eight healthy donors aged 18-32 years, who will undergo extensive clinical screening. Recipients will be randomised 1:1 to receive FMT or placebo, stratified by biological sex. Capsules will be administered over two consecutive days following an overnight bowel cleanse with follow-up assessments at 6, 12 and 26 weeks post-treatment. The primary outcome is GSRS score at 6 weeks. Other assessments include anthropometry, body composition, hair cortisol concentration, gut microbiome profile, urine/plasma gut-derived metabolites, plasma markers of gut inflammation/permeability and questionnaires on general well-being, sleep quality, physical activity, food diversity and treatment tolerability. Adverse events will be recorded and reviewed by an independent data monitoring committee. ETHICS AND DISSEMINATION: Ethics approval for the study was granted by the Central Health and Disability Ethics Committee on 24 August 2021 (reference number: 21/CEN/211). Results will be published in peer-reviewed journals and presented to both scientific and consumer group audiences. TRIAL REGISTRATION NUMBER: ACTRN12622000015741.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Gastroenteropatias , Microbioma Gastrointestinal , Adulto , Humanos , Adolescente , Transtorno Autístico/terapia , Transtorno do Espectro Autista/terapia , Transplante de Microbiota Fecal/métodos , Qualidade de Vida , Gastroenteropatias/terapia , Método Duplo-Cego , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
BMC Med ; 22(1): 39, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287349

RESUMO

BACKGROUND: Nutritional intervention preconception and throughout pregnancy has been proposed as an approach to promoting healthy postnatal weight gain in the offspring but few randomised trials have examined this. METHODS: Measurements of weight and length were obtained at multiple time points from birth to 2 years among 576 offspring of women randomised to receive preconception and antenatally either a supplement containing myo-inositol, probiotics, and additional micronutrients (intervention) or a standard micronutrient supplement (control). We examined the influence on age- and sex-standardised BMI at 2 years (WHO standards, adjusting for study site, sex, maternal parity, smoking and pre-pregnancy BMI, and gestational age), together with the change in weight, length, BMI from birth, and weight gain trajectories using latent class growth analysis. RESULTS: At 2 years, there was a trend towards lower mean BMI among intervention offspring (adjusted mean difference [aMD] - 0.14 SD [95% CI 0.30, 0.02], p = 0.09), and fewer had a BMI > 95th percentile (i.e. > 1.65 SD, 9.2% vs 18.0%, adjusted risk ratio [aRR] 0.51 [95% CI 0.31, 0.82], p = 0.006). Longitudinal data revealed that intervention offspring had a 24% reduced risk of experiencing rapid weight gain > 0.67 SD in the first year of life (21.9% vs 31.1%, aRR 0.76 [95% CI 0.58, 1.00], p = 0.047). The risk was likewise decreased for sustained weight gain > 1.34 SD in the first 2 years of life (7.7% vs 17.1%, aRR 0.55 [95% CI 0.34, 0.88], p = 0.014). From five weight gain trajectories identified, there were more intervention offspring in the "normal" weight gain trajectory characterised by stable weight SDS around 0 SD from birth to 2 years (38.8% vs 30.1%, RR 1.29 [95% CI 1.03, 1.62], p = 0.029). CONCLUSIONS: Supplementation with myo-inositol, probiotics, and additional micronutrients preconception and in pregnancy reduced the incidence of rapid weight gain and obesity at 2 years among offspring. Previous reports suggest these effects will likely translate to health benefits, but longer-term follow-up is needed to evaluate this. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02509988 (Universal Trial Number U1111-1171-8056). Registered on 16 July 2015.


Assuntos
Trajetória do Peso do Corpo , Probióticos , Feminino , Humanos , Gravidez , Índice de Massa Corporal , Suplementos Nutricionais , Inositol , Micronutrientes , Aumento de Peso
7.
PLoS Med ; 20(12): e1004260, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38051700

RESUMO

BACKGROUND: Maternal vitamin status preconception and during pregnancy has important consequences for pregnancy outcome and offspring development. Changes in vitamin status from preconception through early and late pregnancy and postpartum have been inferred from cross-sectional data, but longitudinal data on vitamin status from preconception throughout pregnancy and postdelivery are sparse. As such, the influence of vitamin supplementation on vitamin status during pregnancy remains uncertain. This study presents one prespecified outcome from the randomized controlled NiPPeR trial, aiming to identify longitudinal patterns of maternal vitamin status from preconception, through early and late pregnancy, to 6 months postdelivery, and determine the influence of vitamin supplementation. METHODS AND FINDINGS: In the NiPPeR trial, 1,729 women (from the United Kingdom, Singapore, and New Zealand) aged 18 to 38 years and planning conception were randomized to receive a standard vitamin supplement (control; n = 859) or an enhanced vitamin supplement (intervention; n = 870) starting in preconception and continued throughout pregnancy, with blinding of participants and research staff. Supplement components common to both treatment groups included folic acid, ß-carotene, iron, calcium, and iodine; components additionally included in the intervention group were riboflavin, vitamins B6, B12, and D (in amounts available in over-the-counter supplements), myo-inositol, probiotics, and zinc. The primary outcome of the study was glucose tolerance at 28 weeks' gestation, measured by oral glucose tolerance test. The secondary outcome reported in this study was the reduction in maternal micronutrient insufficiency in riboflavin, vitamin B6, vitamin B12, and vitamin D, before and during pregnancy. We measured maternal plasma concentrations of B-vitamins, vitamin D, and markers of insufficiency/deficiency (homocysteine, hydroxykynurenine-ratio, methylmalonic acid) at recruitment, 1 month after commencing intervention preconception, in early pregnancy (7 to 11 weeks' gestation) and late pregnancy (around 28 weeks' gestation), and postdelivery (6 months after supplement discontinuation). We derived standard deviation scores (SDS) to characterize longitudinal changes among participants in the control group and measured differences between the 2 groups. At recruitment, the proportion of patients with marginal or low plasma status was 29.2% for folate (<13.6 nmol/L), 7.5% and 82.0% for riboflavin (<5 nmol/L and ≤26.5 nmol/L, respectively), 9.1% for vitamin B12 (<221 pmol/L), and 48.7% for vitamin D (<50 nmol/L); these proportions were balanced between the groups. Over 90% of all participants had low or marginal status for one or more of these vitamins at recruitment. Among participants in the control group, plasma concentrations of riboflavin declined through early and late pregnancy, whereas concentrations of 25-hydroxyvitamin D were unchanged in early pregnancy, and concentrations of vitamin B6 and B12 declined throughout pregnancy, becoming >1 SDS lower than baseline by 28 weeks gestation. In the control group, 54.2% of participants developed low late-pregnancy vitamin B6 concentrations (pyridoxal 5-phosphate <20 nmol/L). After 1 month of supplementation, plasma concentrations of supplement components were substantially higher among participants in the intervention group than those in the control group: riboflavin by 0.77 SDS (95% CI 0.68 to 0.87, p < 0.0001), vitamin B6 by 1.07 SDS (0.99 to 1.14, p < 0.0001), vitamin B12 by 0.55 SDS (0.46 to 0.64, p < 0.0001), and vitamin D by 0.51 SDS (0.43 to 0.60, p < 0.0001), with higher levels in the intervention group maintained during pregnancy. Markers of vitamin insufficiency/deficiency were reduced in the intervention group, and the proportion of participants with vitamin D insufficiency (<50 nmol/L) during late pregnancy was lower in the intervention group (35.1% versus 8.5%; p < 0.0001). Plasma vitamin B12 remained higher in the intervention group than in the control group 6 months postdelivery (by 0.30 SDS (0.14, 0.46), p = 0.0003). The main limitation is that generalizability to the global population is limited by the high-resource settings and the lack of African and Amerindian women in particular. CONCLUSIONS: Over 90% of the trial participants had marginal or low concentrations of one or more of folate, riboflavin, vitamin B12, or vitamin D during preconception, and many developed markers of vitamin B6 deficiency in late pregnancy. Preconception/pregnancy supplementation in amounts available in over-the-counter supplements substantially reduces the prevalence of vitamin deficiency and depletion markers before and during pregnancy, with higher maternal plasma vitamin B12 maintained during the recommended lactational period. TRIAL REGISTRATION: ClinicalTrials.gov NCT02509988; U1111-1171-8056.


Assuntos
Ácido Fólico , Complexo Vitamínico B , Feminino , Humanos , Gravidez , Estudos Transversais , Suplementos Nutricionais , Resultado da Gravidez , Riboflavina , Vitamina B 12 , Vitamina B 6 , Vitamina D , Adolescente , Adulto Jovem , Adulto
8.
Nat Mach Intell ; 5(8): 861-872, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37829001

RESUMO

Identifying neoepitopes that elicit an adaptive immune response is a major bottleneck to developing personalized cancer vaccines. Experimental validation of candidate neoepitopes is extremely resource intensive and the vast majority of candidates are non-immunogenic, creating a needle-in-a-haystack problem. Here we address this challenge, presenting computational methods for predicting class I major histocompatibility complex (MHC-I) epitopes and identifying immunogenic neoepitopes with improved precision. The BigMHC method comprises an ensemble of seven pan-allelic deep neural networks trained on peptide-MHC eluted ligand data from mass spectrometry assays and transfer learned on data from assays of antigen-specific immune response. Compared with four state-of-the-art classifiers, BigMHC significantly improves the prediction of epitope presentation on a test set of 45,409 MHC ligands among 900,592 random negatives (area under the receiver operating characteristic = 0.9733; area under the precision-recall curve = 0.8779). After transfer learning on immunogenicity data, BigMHC yields significantly higher precision than seven state-of-the-art models in identifying immunogenic neoepitopes, making BigMHC effective in clinical settings.

9.
Front Endocrinol (Lausanne) ; 14: 1226284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37850096

RESUMO

Newborn screening for congenital adrenal hyperplasia using 17-hydroxyprogesterone by immunoassay remains controversial despite screening been available for almost 40 years. Screening is confounded by poor immunoassay specificity, fetal adrenal physiology, stress, and illness which can result in a large number of false positive screening tests. Screening programmes apply higher screening thresholds based on co-variates such as birthweight or gestational age but the false positive rate using immunoassay remains high. Mass spectrometry was first applied to newborn screening for congenital adrenal hyperplasia over 15 years ago. Elevated 17-hydroxprogesterone by immunoassay can be retested with a specific liquid chromatography tandem mass spectrometry assay that may include additional steroid markers. Laboratories register with quality assurance programme providers to ensure accurate steroid measurements. This has led to improvements in screening but there are additional costs and added laboratory workload. The search for novel steroid markers may inform further improvements to screening. Studies have shown that 11-oxygenated androgens are elevated in untreated patients and that the adrenal steroidogenesis backdoor pathway is more active in babies with congenital adrenal hyperplasia. There is continual interest in 21-deoxycortisol, a specific marker of 21-hydroxylase deficiency. The measurement of androgenic steroids and their precursors by liquid chromatography tandem mass spectrometry in bloodspots may inform improvements for screening, diagnosis, and treatment monitoring. In this review, we describe how liquid chromatography tandem mass spectrometry has improved newborn screening for congenital adrenal hyperplasia and explore how future developments may inform further improvements to screening and diagnosis.


Assuntos
Hiperplasia Suprarrenal Congênita , Recém-Nascido , Humanos , Hiperplasia Suprarrenal Congênita/diagnóstico , Triagem Neonatal/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Esteroides
10.
BMJ Open ; 13(7): e070616, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429676

RESUMO

INTRODUCTION: Individuals with anorexia nervosa (AN) harbour distinct gut microbiomes compared with healthy individuals, which are sufficient to induce weight loss and anxiety-like behaviours when transplanted into germ-free mice. We hypothesise that faecal microbiome transfer (FMT) from healthy donors would help restore the gut microbiome of individuals with AN, which in turn, may aid patient recovery. METHODS: We aim to conduct an open-label pilot study in 20 females aged 16-32 years in Auckland, New Zealand who meet the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) criteria for AN and have a body mass index 13-19 kg/m2. We will recruit four healthy, lean, female donors, aged 18-32 years, who will undergo extensive clinical screening prior to stool donation. Faecal microbiota will be harvested from donors and double encapsulated in delayed release, acid-resistant capsules. All participants will receive a single course of 20 FMT capsules (five from each donor) which they can choose to take over two or four consecutive days. Stool and blood samples will be collected from participants over a period of 3 months to assess their gut microbiome profile, metabolome, levels of intestinal inflammation and nutritional status. Our primary outcome is a shift in the gut microbiome composition at 3 weeks post-FMT (Bray-Curtis dissimilarity). We will also monitor participants' body composition (whole-body dual-energy X-ray absorptiometry scans), eating disorder psychopathology, mental health and assess their views on, and tolerability of, treatment. All adverse events will be recorded and reviewed by an independent data monitoring committee. ETHICS AND DISSEMINATION: Ethics approval was provided by the Central Health and Disability Ethics Committee (Ministry of Health, New Zealand, 21/CEN/212). Results will be published in peer-reviewed journals and presented to both scientific and consumer group audiences. TRIAL REGISTRATION NUMBER: ACTRN12621001504808.


Assuntos
Anorexia Nervosa , Microbioma Gastrointestinal , Microbiota , Feminino , Anorexia Nervosa/terapia , Cápsulas , Projetos Piloto , Humanos , Adolescente , Adulto Jovem , Adulto
11.
Eur J Clin Nutr ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524804

RESUMO

BACKGROUND: Bioimpedance devices are practical for measuring body composition in preschool children, but their application is limited by the lack of validated equations. OBJECTIVES: To develop and validate fat-free mass (FFM) bioimpedance prediction equations among New Zealand 3.5-year olds, with dual-energy X-ray absorptiometry (DXA) as the reference method. METHODS: Bioelectrical impedance spectroscopy (SFB7, ImpediMed) and DXA (iDXA, GE Lunar) measurements were conducted on 65 children. An equation incorporating weight, sex, ethnicity, and impedance was developed and validated. Performance was compared with published equations and mixture theory prediction. RESULTS: The equation developed in ~70% (n = 45) of the population (FFM [kg] = 1.39 + 0.30 weight [kg] + 0.39 length2/resistance at 50 kHz [cm2/Ω] + 0.30 sex [M = 1/F = 0] + 0.28 ethnicity [1 = Asian/0 = non-Asian]) explained 88% of the variance in FFM and predicted FFM with a root mean squared error of 0.39 kg (3.4% of mean FFM). When internally validated (n = 20), bias was small (40 g, 0.3% of mean FFM), with limits of agreement (LOA) ±7.6% of mean FFM (95% LOA: -0.82, 0.90 kg). Published equations evaluated had similar LOA, but with marked bias (>12.5% of mean FFM) when validated in our cohort, likely due to DXA differences. Of mixture theory methods assessed, the SFB7 inbuilt equation with personalized body geometry values performed best. However, bias and LOA were larger than with the empirical equations (-0.43 kg [95% LOA: -1.65, 0.79], p < 0.001). CONCLUSIONS: We developed and validated a bioimpedance equation that can accurately predict FFM. Further external validation of the equation is required.

12.
Front Plant Sci ; 14: 1171564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404542

RESUMO

Nowadays, many products are available in the plant biostimulants market. Among them, living yeast-based biostimulants are also commercialized. Given the living aspect of these last products, the reproducibility of their effects should be investigated to ensure end-users' confidence. Therefore, this study aimed to compare the effects of a living yeast-based biostimulant between two different soybean cultures. These two cultures named C1 and C2 were conducted on the same variety and soil but in different locations and dates until the VC developmental stage (unifoliate leaves unrolled), with Bradyrhizobium japonicum (control and Bs condition) and with and without biostimulant coating seed treatment. The foliar transcriptomic analysis done first showed a high gene expression difference between the two cultures. Despite this first result, a secondary analysis seemed to show that this biostimulant led to a similar pathway enhancement in plants and with common genes even if the expressed genes were different between the two cultures. The pathways which seem to be reproducibly impacted by this living yeast-based biostimulant are abiotic stress tolerance and cell wall/carbohydrate synthesis. Impacting these pathways may protect the plant from abiotic stresses and maintain a higher level of sugars in plant.

13.
Expert Opin Biol Ther ; 23(6): 553-564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37171790

RESUMO

INTRODUCTION: Heart valve disease is a growing burden on the healthcare system. Current solutions are insufficient for young patients and do not offer relief from reintervention. Tissue engineered heart valves (TEHVs) offer a solution that grows and responds to the native environment in a similar way to a healthy valve. Stem cells hold potential to populate these valves as a malleable source that can adapt to environmental cues. AREAS COVERED: This review covers current methods of recapitulating features of native heart valves with tissue engineering through use of stem cell populations with in situ and in vitro methods. EXPERT OPINION: In the field of TEHVs, we see a variety of approaches in cell source, biomaterial, and maturation methods. Choosing appropriate cell populations may be very patient specific; consistency and predictability will be key to long-term success. In situ methods are closer to translation but struggle with consistent cellularization. In vitro culture requires specialized methods but may recapitulate native valve cell populations with higher fidelity. Understanding how cell populations react to valve conditions and immune response is vital for success. Detrimental valve pathologies have proven to be difficult to avoid in early translation attempts.


Assuntos
Próteses Valvulares Cardíacas , Engenharia Tecidual , Humanos , Valvas Cardíacas , Células-Tronco , Materiais Biocompatíveis
14.
bioRxiv ; 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37205480

RESUMO

Ribosome assembly requires precise coordination between the production and assembly of ribosomal components. Mutations in ribosomal proteins that inhibit the assembly process or ribosome function are often associated with Ribosomopathies, some of which are linked to defects in proteostasis. In this study, we examine the interplay between several yeast proteostasis enzymes, including deubiquitylases (DUBs), Ubp2 and Ubp14, and E3 ligases, Ufd4 and Hul5, and we explore their roles in the regulation of the cellular levels of K29-linked unanchored polyubiquitin (polyUb) chains. Accumulating K29-linked unanchored polyUb chains associate with maturing ribosomes to disrupt their assembly, activate the Ribosome assembly stress response (RASTR), and lead to the sequestration of ribosomal proteins at the Intranuclear Quality control compartment (INQ). These findings reveal the physiological relevance of INQ and provide insights into mechanisms of cellular toxicity associated with Ribosomopathies.

15.
Lancet Glob Health ; 11 Suppl 1: S11-S12, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36866469

RESUMO

BACKGROUND: Nutritional intervention before and throughout pregnancy might promote healthy infant weight gain; however, clinical evidence is scarce. Therefore, we examined whether preconception and antenatal supplementation would affect the body size and growth of children in the first 2 years of life. METHODS: Women were recruited from the community before conception in the UK, Singapore, and New Zealand, and randomly allocated to either the intervention (myo-inositol, probiotics, and additional micronutrients) or control group (standard micronutrient supplement) with stratification by site and ethnicity. Measurements of weight and length were obtained from 576 children at multiple timepoints in the first 2 years of life. Differences in age and sex standardised BMI at age 2 years (WHO standards) and the change in weight from birth were examined. Written informed consent was obtained from the mothers, and ethics approval was granted by local committees. The NiPPeR trial was registered with ClinicalTrials.gov (NCT02509988) on July 16, 2015 (Universal Trial Number U1111-1171-8056). FINDINGS: 1729 women were recruited between Aug 3, 2015, and May 31, 2017. Of the women randomised, 586 had births at 24 weeks or more of gestation between April, 2016, and January, 2019. At age 2 years, adjusting for study site, infant sex, parity, maternal smoking, maternal prepregnancy BMI, and gestational age, fewer children of mothers who received the intervention had a BMI of more than the 95th percentile (22 [9%] of 239 vs 44 [18%] of 245, adjusted risk ratio 0·51, 95% CI 0·31-0·82, p=0·006). Longitudinal data revealed that the children of mothers who received the intervention had a 24% reduced risk of experiencing rapid weight gain of more than 0·67 SD in the first year of life (58 [21·9%] of 265 vs 80 [31·1%] of 257, adjusted risk ratio 0·76, 95% CI 0·58-1·00, p=0·047). Risk was likewise decreased for sustained weight gain of more than 1·34 SD in the first 2 years (19 [7·7%] of 246 vs 43 [17·1%] of 251, adjusted risk ratio 0·55, 95% CI 0·34-0·88, p=0·014). INTERPRETATION: Rapid weight gain in infancy is associated with future adverse metabolic health. The intervention supplement taken before and throughout pregnancy was associated with lower risk of rapid weight gain and high BMI at age 2 years among children. Long-term follow-up is required to assess the longevity of these benefits. FUNDING: National Institute for Health Research; New Zealand Ministry of Business, Innovation and Employment; Société Des Produits Nestlé; UK Medical Research Council; Singapore National Research Foundation; National University of Singapore and the Agency of Science, Technology and Research; and Gravida.


Assuntos
Comércio , Suplementos Nutricionais , Gravidez , Lactente , Humanos , Criança , Feminino , Pré-Escolar , Índice de Massa Corporal , Emprego , Etnicidade
16.
Genome Biol ; 24(1): 30, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36803582

RESUMO

BACKGROUND: The Ccr4-Not complex is mostly known as the major eukaryotic deadenylase. However, several studies have uncovered roles of the complex, in particular of the Not subunits, unrelated to deadenylation and relevant for translation. In particular, the existence of Not condensates that regulate translation elongation dynamics has been reported. Typical studies that evaluate translation efficiency rely on soluble extracts obtained after the disruption of cells and ribosome profiling. Yet cellular mRNAs in condensates can be actively translated and may not be present in such extracts. RESULTS: In this work, by analyzing soluble and insoluble mRNA decay intermediates in yeast, we determine that insoluble mRNAs are enriched for ribosomes dwelling at non-optimal codons compared to soluble mRNAs. mRNA decay is higher for soluble RNAs, but the proportion of co-translational degradation relative to the overall mRNA decay is higher for insoluble mRNAs. We show that depletion of Not1 and Not4 inversely impacts mRNA solubilities and, for soluble mRNAs, ribosome dwelling according to codon optimality. Depletion of Not4 solubilizes mRNAs with lower non-optimal codon content and higher expression that are rendered insoluble by Not1 depletion. By contrast, depletion of Not1 solubilizes mitochondrial mRNAs, which are rendered insoluble upon Not4 depletion. CONCLUSIONS: Our results reveal that mRNA solubility defines the dynamics of co-translation events and is oppositely regulated by Not1 and Not4, a mechanism that we additionally determine may already be set by Not1 promoter association in the nucleus.


Assuntos
Ribossomos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Códon/metabolismo , Biossíntese de Proteínas , Ribossomos/metabolismo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Solubilidade , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
17.
Am J Clin Nutr ; 117(5): 883-895, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36781129

RESUMO

BACKGROUND: Maternal obesity during pregnancy is associated with an increased risk of obesity and metabolic disease in the offspring. Supplementation with fish oil (FO), which is insulin sensitizing, during pregnancy in mothers with overweight or obesity may prevent the development of greater adiposity and metabolic dysfunction in their children. OBJECTIVES: To determine the effects of FO supplementation throughout the second half of pregnancy and lactation in mothers with overweight or obesity on infant body composition and metabolism. METHODS: A double-blind randomized controlled trial of 6 g FO (3.55 g/d of n-3 PUFAs) compared with olive oil (control) from mid-pregnancy until 3 mo postpartum. Eligible women had singleton pregnancies at 12-20 wk of gestation, and BMI ≥ 25 kg/m2. The primary outcome was the infant body fat percentage (DXA scans) at 2 wk of age. Secondary outcomes included maternal metabolic markers during pregnancy, infant anthropometry at 2 wk and 3 mo of age, and metabolic markers at 3 mo. RESULTS: A total of 129 mothers were randomized, and 98 infants had a DXA scan at 2 wk. PRIMARY OUTCOME: Imputed and nonimputed analyses showed no effects of FO supplementation on infant body fat percentage at age 2 wk. SECONDARY OUTCOMES: There were no treatment effects on infant outcomes at 2 wk, but FO infants had a higher BMI z-score (P = 0.025) and ponderal index (P = 0.017) at age 3 mo. FO supplementation lowered maternal triglycerides by 17% at 30 wk of pregnancy (P = 0.0002) and infant triglycerides by 21% at 3 mo of age (P = 0.016) but did not affect maternal or infant insulin resistance. The rate of emergency cesarean section was lower with FO supplementation [aRR = 0.38 (95%CI 0.16, 0.90); P = 0.027]. CONCLUSIONS: FO supplementation of mothers with overweight or obesity during pregnancy did not impact infant body composition. There is a need to follow up the offspring to determine whether the observed metabolic effects persist. CLINICAL TRIAL REGISTRY NUMBER: This study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12617001078347p). In addition, the Universal Trial Number, WHO, was obtained (U1111-1199-5860).


Assuntos
Óleos de Peixe , Sobrepeso , Feminino , Lactente , Gravidez , Humanos , Cesárea , Suplementos Nutricionais , Austrália , Obesidade/terapia , Composição Corporal , Lactação , Método Duplo-Cego , Triglicerídeos/farmacologia
18.
Nucleic Acids Res ; 51(2): 744-764, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36610750

RESUMO

Ribosomes are ribozymes, hence correct folding of the rRNAs during ribosome biogenesis is crucial to ensure catalytic activity. RNA helicases, which can modulate RNA-RNA and RNA/protein interactions, are proposed to participate in rRNA tridimensional folding. Here, we analyze the biochemical properties of Dbp6, a DEAD-box RNA helicase required for the conversion of the initial 90S pre-ribosomal particle into the first pre-60S particle. We demonstrate that in vitro, Dbp6 shows ATPase as well as annealing and clamping activities negatively regulated by ATP. Mutations in Dbp6 core motifs involved in ATP binding and ATP hydrolysis are lethal and impair Dbp6 ATPase activity but increase its RNA binding and RNA annealing activities. These data suggest that correct regulation of these activities is important for Dbp6 function in vivo. Using in vivo cross-linking (CRAC) experiments, we show that Dbp6 interacts with 25S rRNA sequences located in the 5' domain I and in the peptidyl transferase center (PTC), and also crosslinks to snoRNAs hybridizing to the immature PTC. We propose that the ATPase and RNA clamping/annealing activities of Dbp6 modulate interactions of snoRNAs with the immature PTC and/or contribute directly to the folding of this region.


Assuntos
RNA Helicases DEAD-box , Ribossomos , Proteínas de Saccharomyces cerevisiae , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Peptidil Transferases/genética , Peptidil Transferases/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , RNA Helicases/genética , RNA Ribossômico/metabolismo , RNA Nucleolar Pequeno/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
20.
Front Physiol ; 13: 923704, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518108

RESUMO

Type 2 diabetes mellitus is a complex and under-treated disorder closely intertwined with obesity. Adolescents with severe obesity and type 2 diabetes have a more aggressive disease compared to adults, with a rapid decline in pancreatic ß cell function and increased incidence of comorbidities. Given the relative paucity of pharmacotherapies, bariatric surgery has become increasingly used as a therapeutic option. However, subsets of this population have sub-optimal outcomes with either inadequate weight loss or little improvement in disease. Predicting which patients will benefit from surgery is a difficult task and detailed physiological characteristics of patients who do not respond to treatment are generally unknown. Identifying physiological predictors of surgical response therefore has the potential to reveal both novel phenotypes of disease as well as therapeutic targets. We leverage data assimilation paired with mechanistic models of glucose metabolism to estimate pre-operative physiological states of bariatric surgery patients, thereby identifying latent phenotypes of impaired glucose metabolism. Specifically, maximal insulin secretion capacity, σ, and insulin sensitivity, SI, differentiate aberrations in glucose metabolism underlying an individual's disease. Using multivariable logistic regression, we combine clinical data with data assimilation to predict post-operative glycemic outcomes at 12 months. Models using data assimilation sans insulin had comparable performance to models using oral glucose tolerance test glucose and insulin. Our best performing models used data assimilation and had an area under the receiver operating characteristic curve of 0.77 (95% confidence interval 0.7665, 0.7734) and mean average precision of 0.6258 (0.6206, 0.6311). We show that data assimilation extracts knowledge from mechanistic models of glucose metabolism to infer future glycemic states from limited clinical data. This method can provide a pathway to predict long-term, post-surgical glycemic states by estimating the contributions of insulin resistance and limitations of insulin secretion to pre-operative glucose metabolism.

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