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1.
Cell ; 180(5): 968-983.e24, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32109415

RESUMEN

Mammalian tissues engage in specialized physiology that is regulated through reversible modification of protein cysteine residues by reactive oxygen species (ROS). ROS regulate a myriad of biological processes, but the protein targets of ROS modification that drive tissue-specific physiology in vivo are largely unknown. Here, we develop Oximouse, a comprehensive and quantitative mapping of the mouse cysteine redox proteome in vivo. We use Oximouse to establish several paradigms of physiological redox signaling. We define and validate cysteine redox networks within each tissue that are tissue selective and underlie tissue-specific biology. We describe a common mechanism for encoding cysteine redox sensitivity by electrostatic gating. Moreover, we comprehensively identify redox-modified disease networks that remodel in aged mice, establishing a systemic molecular basis for the long-standing proposed links between redox dysregulation and tissue aging. We provide the Oximouse compendium as a framework for understanding mechanisms of redox regulation in physiology and aging.


Asunto(s)
Envejecimiento/genética , Cisteína/genética , Proteínas/genética , Proteoma/genética , Envejecimiento/metabolismo , Envejecimiento/patología , Animales , Cisteína/metabolismo , Humanos , Ratones , Especificidad de Órganos/genética , Oxidación-Reducción , Estrés Oxidativo/genética , Proteómica/métodos , Especies Reactivas de Oxígeno , Transducción de Señal/genética
2.
Nat Immunol ; 22(6): 746-756, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34031618

RESUMEN

T cell exhaustion presents one of the major hurdles to cancer immunotherapy. Among exhausted CD8+ tumor-infiltrating lymphocytes, the terminally exhausted subset contributes directly to tumor cell killing owing to its cytotoxic effector function. However, this subset does not respond to immune checkpoint blockades and is difficult to be reinvigorated with restored proliferative capacity. Here, we show that a half-life-extended interleukin-10-Fc fusion protein directly and potently enhanced expansion and effector function of terminally exhausted CD8+ tumor-infiltrating lymphocytes by promoting oxidative phosphorylation, a process that was independent of the progenitor exhausted T cells. Interleukin-10-Fc was a safe and highly efficient metabolic intervention that synergized with adoptive T cell transfer immunotherapy, leading to eradication of established solid tumors and durable cures in the majority of treated mice. These findings show that metabolic reprogramming by upregulating mitochondrial pyruvate carrier-dependent oxidative phosphorylation can revitalize terminally exhausted T cells and enhance the response to cancer immunotherapy.


Asunto(s)
Inmunoterapia Adoptiva/métodos , Interleucina-10/farmacología , Neoplasias/terapia , Fosforilación Oxidativa/efectos de los fármacos , Linfocitos T Citotóxicos/efectos de los fármacos , Animales , Proteínas de Transporte de Anión/genética , Proteínas de Transporte de Anión/metabolismo , Línea Celular Tumoral , Terapia Combinada/métodos , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Femenino , Células HEK293 , Semivida , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Fragmentos Fc de Inmunoglobulinas/farmacología , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Interleucina-10/uso terapéutico , Ratones , Ratones Transgénicos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neoplasias/inmunología , Neoplasias/patología , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/metabolismo , Receptores de Interleucina-10/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Proteínas Recombinantes de Fusión/uso terapéutico , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Linfocitos T Citotóxicos/citología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo
3.
Nature ; 606(7912): 94-101, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35650358

RESUMEN

Neurotransmitters play essential roles in regulating neural circuit dynamics both in the central nervous system as well as at the peripheral, including the gastrointestinal tract1-3. Their real-time monitoring will offer critical information for understanding neural function and diagnosing disease1-3. However, bioelectronic tools to monitor the dynamics of neurotransmitters in vivo, especially in the enteric nervous systems, are underdeveloped. This is mainly owing to the limited availability of biosensing tools that are capable of examining soft, complex and actively moving organs. Here we introduce a tissue-mimicking, stretchable, neurochemical biological interface termed NeuroString, which is prepared by laser patterning of a metal-complexed polyimide into an interconnected graphene/nanoparticle network embedded in an elastomer. NeuroString sensors allow chronic in vivo real-time, multichannel and multiplexed monoamine sensing in the brain of behaving mouse, as well as measuring serotonin dynamics in the gut without undesired stimulations and perturbing peristaltic movements. The described elastic and conformable biosensing interface has broad potential for studying the impact of neurotransmitters on gut microbes, brain-gut communication and may ultimately be extended to biomolecular sensing in other soft organs across the body.


Asunto(s)
Encéfalo , Sistema Nervioso Entérico , Tracto Gastrointestinal , Neurotransmisores , Animales , Técnicas Biosensibles , Encéfalo/metabolismo , Eje Cerebro-Intestino , Elastómeros , Sistema Nervioso Entérico/metabolismo , Tracto Gastrointestinal/inervación , Tracto Gastrointestinal/fisiología , Grafito , Rayos Láser , Ratones , Nanopartículas , Neurotransmisores/análisis , Serotonina/análisis
4.
Nature ; 589(7841): 214-219, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408416

RESUMEN

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

5.
Proc Natl Acad Sci U S A ; 120(19): e2212118120, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37126683

RESUMEN

The prognosis and treatment outcomes of heart failure (HF) patients rely heavily on disease etiology, yet the majority of underlying signaling mechanisms are complex and not fully elucidated. Phosphorylation is a major point of protein regulation with rapid and profound effects on the function and activity of protein networks. Currently, there is a lack of comprehensive proteomic and phosphoproteomic studies examining cardiac tissue from HF patients with either dilated dilated cardiomyopathy (DCM) or ischemic cardiomyopathy (ICM). Here, we used a combined proteomic and phosphoproteomic approach to identify and quantify more than 5,000 total proteins with greater than 13,000 corresponding phosphorylation sites across explanted left ventricle (LV) tissue samples, including HF patients with DCM vs. nonfailing controls (NFC), and left ventricular infarct vs. noninfarct, and periinfarct vs. noninfarct regions of HF patients with ICM. Each pair-wise comparison revealed unique global proteomic and phosphoproteomic profiles with both shared and etiology-specific perturbations. With this approach, we identified a DCM-associated hyperphosphorylation cluster in the cardiomyocyte intercalated disc (ICD) protein, αT-catenin (CTNNA3). We demonstrate using both ex vivo isolated cardiomyocytes and in vivo using an AAV9-mediated overexpression mouse model, that CTNNA3 phosphorylation at these residues plays a key role in maintaining protein localization at the cardiomyocyte ICD to regulate conductance and cell-cell adhesion. Collectively, this integrative proteomic/phosphoproteomic approach identifies region- and etiology-associated signaling pathways in human HF and describes a role for CTNNA3 phosphorylation in the pathophysiology of DCM.


Asunto(s)
Cardiomiopatía Dilatada , Insuficiencia Cardíaca , Animales , Ratones , Humanos , Cardiomiopatía Dilatada/metabolismo , Ventrículos Cardíacos/metabolismo , Fosforilación , Proteómica , Miocardio/metabolismo , Insuficiencia Cardíaca/metabolismo , alfa Catenina/metabolismo
6.
Dev Biol ; 512: 57-69, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38750688

RESUMEN

Understanding the developmental processes and signaling pathways involved in larval myogenesis and metamorphosis is crucial for comprehending the life history and adaptive strategies of marine organisms. In this study, we investigated the temporal and spatial patterns of myogenesis in the mussel Mytilus coruscus (Mc), focusing on the emergence and transformation of major muscle groups during different larval stages. We also explored the role of the Hedgehog (Hh) signaling pathway in regulating myogenesis and larval metamorphosis. The results revealed distinct developmental stages characterized by the emergence of specific muscular components, such as velum retractor muscles and anterior adductor muscles, in D-veliger and umbo larvae, which are responsible for the planktonic stage. In the pediveliger stage, posterior ventral, posterior adductor, and foot muscles appeared. After larval metamorphosis, the velum structure and its corresponding retractor muscles degenerate, indicating the transition from planktonic to benthic life. We observed a conserved pattern of larval musculature development and revealed a high degree of conservation across bivalve species, with comparable emergence times during myogenesis. Furthermore, exposure to the Hh signaling inhibitor cyclopamine impaired larval muscle development, reduced larval swimming activity, and inhibited larval metamorphosis in M. coruscus. Cyclopamine-mediated inhibition of Hh signaling led to reduced expression of four key genes within the Hh signaling pathway (McHh, McPtc, McSmo, and McGli) and the striated myosin heavy chain gene (McMHC). It is hypothesised that the abnormal larval muscle development in cyclopamine-treated groups may be an indirect effect due to disrupted McMHC expression. We provide evidence for the first time that cyclopamine treatment inhibited larval metamorphosis in bivalves, highlighting the potential involvement of Hh signaling in mediating larval muscle development and metamorphosis in M. coruscus. The present study provides insights into the dynamic nature of myogenesis and the regulatory role of the Hh signaling pathway during larval development and metamorphosis in M. coruscus. The results obtained in this study contribute to a better understanding of the evolutionary significance of Hh signaling in bivalves and shed light on the mechanisms underlying larval muscle development and metamorphosis in marine invertebrates.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Proteínas Hedgehog , Larva , Metamorfosis Biológica , Desarrollo de Músculos , Mytilus , Transducción de Señal , Animales , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Larva/crecimiento & desarrollo , Larva/metabolismo , Mytilus/crecimiento & desarrollo , Mytilus/metabolismo , Alcaloides de Veratrum/farmacología , Músculos/metabolismo
7.
Development ; 149(12)2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35587592

RESUMEN

Vascular establishment is one of the early events in embryogenesis. It is believed that vessel-initiating endothelial progenitors cluster to form the first primitive vessel. Understanding the molecular identity of these progenitors is crucial in order to elucidate lineage hierarchy. In this study, we identify protein C receptor (Procr) as an endothelial progenitor marker and investigate the role of Procr+ progenitors during embryonic vascular development. Using a ProcrmGFP-2A-lacZ reporter, we reveal a much earlier Procr expression (embryonic day 7.5) than previously acknowledged (embryonic day 13.5). Genetic fate-mapping experiments using ProcrCre and ProcrCreER demonstrate that Procr+ cells give rise to blood vessels throughout the entire embryo proper. Single-cell RNA-sequencing analyses place Procr+ cells at the start of endothelial commitment and maturation. Furthermore, targeted ablation of Procr+ cells results in failure of vessel formation and early embryonic lethality. Notably, genetic fate mapping and scRNA-seq pseudotime analysis support the view that Procr+ progenitors can give rise to hemogenic endothelium. In this study, we establish a Procr expression timeline and identify Procr+ vessel-initiating progenitors, and demonstrate their indispensable role in establishment of the vasculature during embryo development.


Asunto(s)
Hemangioblastos , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Receptor de Proteína C Endotelial/genética , Receptor de Proteína C Endotelial/metabolismo , Hemangioblastos/metabolismo
8.
Immunity ; 44(6): 1337-49, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27317260

RESUMEN

Distinct metabolic programs support the differentiation of CD4(+) T cells into separate functional subsets. In this study, we investigated metabolic mechanisms underlying the differentiation of IL-9-producing CD4(+) T cells (Th9) in allergic airway inflammation and cancerous tumors. We found that histone deacetylase SIRT1 negatively regulated Th9 cell differentiation. A deficiency of SIRT1 induced by either conditional deletion in mouse CD4(+) T cells or the use of small interfering RNA (siRNA) in mouse or human T cells increased IL-9 production, whereas ectopic SIRT1 expression inhibited it. Notably, SIRT1 inhibited Th9 cell differentiation that regulated anti-tumor immunity and allergic pulmonary inflammation. Glycolytic activation through the mTOR-hypoxia-inducible factor-1α (HIF1α) was required for the differentiation of Th9 cells that conferred protection against tumors and is involved in allergic airway inflammation. Our results define the essential features of SIRT1-mTOR-HIF1α signaling-coupled glycolytic pathway in inducing Th9 cell differentiation, with implications for metabolic reprogramming as an immunotherapeutic approach.


Asunto(s)
Hipersensibilidad/inmunología , Melanoma/inmunología , Sirtuina 1/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Diferenciación Celular , Células Cultivadas , Glucólisis , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Interleucina-9/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Melanoma Experimental , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias Experimentales , ARN Interferente Pequeño/genética , Transducción de Señal , Sirtuina 1/genética , Serina-Treonina Quinasas TOR/metabolismo , Activación Transcripcional
9.
Nature ; 576(7786): 287-292, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31776510

RESUMEN

Mammals form scars to quickly seal wounds and ensure survival by an incompletely understood mechanism1-5. Here we show that skin scars originate from prefabricated matrix in the subcutaneous fascia. Fate mapping and live imaging revealed that fascia fibroblasts rise to the skin surface after wounding, dragging their surrounding extracellular jelly-like matrix, including embedded blood vessels, macrophages and peripheral nerves, to form the provisional matrix. Genetic ablation of fascia fibroblasts prevented matrix from homing into wounds and resulted in defective scars, whereas placing an impermeable film beneath the skin-preventing fascia fibroblasts from migrating upwards-led to chronic open wounds. Thus, fascia contains a specialized prefabricated kit of sentry fibroblasts, embedded within a movable sealant, that preassemble together diverse cell types and matrix components needed to heal wounds. Our findings suggest that chronic and excessive skin wounds may be attributed to the mobility of the fascia matrix.


Asunto(s)
Fascia/patología , Cicatrización de Heridas , Animales , Biomarcadores/análisis , Movimiento Celular , Fascia/trasplante , Fibroblastos , Queloide , Ratones Endogámicos C57BL
10.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38436467

RESUMEN

Previous working memory research has demonstrated robust stimulus representations during memory maintenance in both voltage and alpha-band activity in electroencephalography. However, the exact functions of these 2 neural signatures have remained controversial. Here we systematically investigated their respective contributions to memory manipulation. Human participants either maintained a previously seen spatial location, or manipulated the location following a mental rotation cue over a delay. Using multivariate decoding, we observed robust location representations in low-frequency voltage and alpha-band oscillatory activity with distinct spatiotemporal dynamics: location representations were most evident in posterior channels in alpha-band activity, but were most prominent in the more anterior, central channels in voltage signals. Moreover, the temporal emergence of manipulated representation in central voltage preceded that in posterior alpha-band activity, suggesting that voltage might carry stimulus-specific source signals originated internally from anterior cortex, whereas alpha-band activity might reflect feedback signals in posterior cortex received from higher-order cortex. Lastly, while location representations in both signals were coded in a low-dimensional neural subspace, location representation in central voltage was higher-dimensional and underwent a representational transformation that exclusively predicted memory behavior. Together, these results highlight the crucial role of central voltage in working memory, and support functional distinctions between voltage and alpha-band activity.


Asunto(s)
Corteza Cerebral , Memoria a Corto Plazo , Humanos , Electroencefalografía
11.
Proc Natl Acad Sci U S A ; 119(32): e2122854119, 2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-35914153

RESUMEN

There are over 250,000 international treaties that aim to foster global cooperation. But are treaties actually helpful for addressing global challenges? This systematic field-wide evidence synthesis of 224 primary studies and meta-analysis of the higher-quality 82 studies finds treaties have mostly failed to produce their intended effects. The only exceptions are treaties governing international trade and finance, which consistently produced intended effects. We also found evidence that impactful treaties achieve their effects through socialization and normative processes rather than longer-term legal processes and that enforcement mechanisms are the only modifiable treaty design choice with the potential to improve the effectiveness of treaties governing environmental, human rights, humanitarian, maritime, and security policy domains. This evidence synthesis raises doubts about the value of international treaties that neither regulate trade or finance nor contain enforcement mechanisms.

12.
J Neurosci ; 43(38): 6508-6524, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37582626

RESUMEN

Humans constantly receive massive amounts of information, both perceived from the external environment and imagined from the internal world. To function properly, the brain needs to correctly identify the origin of information being processed. Recent work has suggested common neural substrates for perception and imagery. However, it has remained unclear how the brain differentiates between external and internal experiences with shared neural codes. Here we tested this question in human participants (male and female) by systematically investigating the neural processes underlying the generation and maintenance of visual information from voluntary imagery, veridical perception, and illusion. The inclusion of illusion allowed us to differentiate between objective and subjective internality: while illusion has an objectively internal origin and can be viewed as involuntary imagery, it is also subjectively perceived as having an external origin like perception. Combining fMRI, eye-tracking, multivariate decoding, and encoding approaches, we observed superior orientation representations in parietal cortex during imagery compared with perception, and conversely in early visual cortex. This imagery dominance gradually developed along a posterior-to-anterior cortical hierarchy from early visual to parietal cortex, emerged in the early epoch of imagery and sustained into the delay epoch, and persisted across varied imagined contents. Moreover, representational strength of illusion was more comparable to imagery in early visual cortex, but more comparable to perception in parietal cortex, suggesting content-specific representations in parietal cortex differentiate between subjectively internal and external experiences, as opposed to early visual cortex. These findings together support a domain-general engagement of parietal cortex in internally generated experience.SIGNIFICANCE STATEMENT How does the brain differentiate between imagined and perceived experiences? Combining fMRI, eye-tracking, multivariate decoding, and encoding approaches, the current study revealed enhanced stimulus-specific representations in visual imagery originating from parietal cortex, supporting the subjective experience of imagery. This neural principle was further validated by evidence from visual illusion, wherein illusion resembled perception and imagery at different levels of cortical hierarchy. Our findings provide direct evidence for the critical role of parietal cortex as a domain-general region for content-specific imagery, and offer new insights into the neural mechanisms underlying the differentiation between subjectively internal and external experiences.


Asunto(s)
Ilusiones , Percepción Visual , Humanos , Masculino , Femenino , Imaginación , Lóbulo Parietal , Encéfalo , Mapeo Encefálico , Imagen por Resonancia Magnética
13.
J Proteome Res ; 23(5): 1834-1843, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38594897

RESUMEN

GoDig, a platform for targeted pathway proteomics without the need for manual assay scheduling or synthetic standards, is a powerful, flexible, and easy-to-use method that uses tandem mass tags to increase sample throughput up to 18-fold relative to label-free methods. Though the protein-level success rates of GoDig are high, the peptide-level success rates are more limited, hampering assays of harder-to-quantify proteins and site-specific phenomena. To guide the optimization of GoDig assays as well as improvements to the GoDig platform, we created GoDigViewer, a new stand-alone software that provides detailed visualizations of GoDig runs. GoDigViewer guided the implementation of "priming runs," an acquisition mode with significantly higher success rates. In this mode, two or more chromatographic priming runs are automatically performed to improve the accuracy and precision of target elution orders, followed by analytical runs which quantify targets. Using priming runs, success rates exceeded 97% for a list of 400 peptide targets and 95% for a list of 200 targets that are usually not quantified using untargeted mass spectrometry. We used priming runs to establish a quantitative assay of 125 macroautophagy proteins that had a >95% success rate and revealed differences in macroautophagy expression profiles across four human cell lines.


Asunto(s)
Proteómica , Programas Informáticos , Espectrometría de Masas en Tándem , Proteómica/métodos , Humanos , Espectrometría de Masas en Tándem/métodos , Péptidos/análisis , Cromatografía Liquida/métodos , Autofagia
14.
J Proteome Res ; 23(1): 142-148, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38009700

RESUMEN

Targeted proteomics strategies present a streamlined hypothesis-driven approach to analyze specific sets of pathways or disease related proteins. goDig is a quantitative, targeted tandem mass tag (TMT)-based assay that can measure the relative abundance differences for hundreds of proteins directly from unfractionated mixtures. Specific protein groups or entire pathways of up to 200 proteins can be selected for quantitative profiling, while leveraging sample multiplexing permits the simultaneous analysis of up to 18 samples. Despite these benefits, implementing goDig is not without challenges, as it requires access to an instrument application programming interface (iAPI), an elution order and spectral library, a web-based method builder, and dedicated companion software. In addition, the absence of an example test assay may dissuade researchers from testing or implementing goDig. Here, we repurpose the TKO11 standard─which is commercially available but may also be assembled in-lab─and establish it as a de facto test assay for goDig. We build a proteome-wide goDig yeast library, quantify protein expression across several gene ontology (GO) categories, and compare these results to a fully fractionated yeast gold-standard data set. Essentially, we provide a guide detailing the goDig-based quantification of TKO11, which can also be used as a template for user-defined assays in other species.


Asunto(s)
Saccharomyces cerevisiae , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Proteómica/métodos , Programas Informáticos , Proteoma/análisis
15.
Plant J ; 115(4): 986-1003, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37158657

RESUMEN

The accumulation of carotenoids, such as xanthophylls, lycopene, and carotenes, is responsible for the color of carrot (Daucus carota subsp. sativus) fleshy roots. The potential role of DcLCYE, encoding a lycopene ε-cyclase associated with carrot root color, was investigated using cultivars with orange and red roots. The expression of DcLCYE in red carrot varieties was significantly lower than that in orange carrots at the mature stage. Furthermore, red carrots accumulated larger amounts of lycopene and lower levels of α-carotene. Sequence comparison and prokaryotic expression analysis revealed that amino acid differences in red carrots did not affect the cyclization function of DcLCYE. Analysis of the catalytic activity of DcLCYE revealed that it mainly formed ε-carotene, while a side activity on α-carotene and γ-carotene was also observed. Comparative analysis of the promoter region sequences indicated that differences in the promoter region may affect the transcription of DcLCYE. DcLCYE was overexpressed in the red carrot 'Benhongjinshi' under the control of the CaMV35S promoter. Lycopene in transgenic carrot roots was cyclized, resulting in the accumulation of higher levels of α-carotene and xanthophylls, while the ß-carotene content was significantly decreased. The expression levels of other genes in the carotenoid pathway were simultaneously upregulated. Knockout of DcLCYE in the orange carrot 'Kurodagosun' by CRISPR/Cas9 technology resulted in a decrease in the α-carotene and xanthophyll contents. The relative expression levels of DcPSY1, DcPSY2, and DcCHXE were sharply increased in DcLCYE knockout mutants. The results of this study provide insights into the function of DcLCYE in carrots, which could serve as a basis for creating colorful carrot germplasms.


Asunto(s)
Daucus carota , beta Caroteno , beta Caroteno/metabolismo , Daucus carota/genética , Licopeno/metabolismo , Carotenoides/metabolismo , Xantófilas/metabolismo
16.
J Am Chem Soc ; 146(21): 14445-14452, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38739877

RESUMEN

Transition-metal-catalyzed C-Si/Ge cross-coupling offers promising avenues for the synthesis of organosilanes/organogermanes, yet it is fraught with long-standing challenges. A Ni/Ti-catalyzed strategy is reported here, allowing the use of disubstituted malononitriles as tertiary C(sp3) coupling partners to couple with chlorosilanes and chlorogermanes, respectively. This method enables the catalytic cleavage of the C(sp3)-CN bond of the quaternary carbon followed by the formation of C(sp3)-Si/C(sp3)-Ge bonds from ubiquitously available starting materials. The efficiency and generality are showcased by a broad scope for both of the coupling partners, therefore holding the potential to synthesize structurally diverse quaternary organosilanes and organogermanes that were difficult to access previously.

17.
Hum Mol Genet ; 31(15): 2498-2507, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35165721

RESUMEN

Tau oligomers (oTau) are thought to precede neurofibrillary tangle formation and likely represent one of the toxic species in disease. This study addresses whether mitochondrial reactive oxygen species (ROS) contribute to tau oligomer accumulation. First, we determined whether elevated oxidative stress correlates with aggregation of tau oligomers in the brain and platelets of human Alzheimer's disease (AD) patient, tauopathy mice, primary cortical neurons from tau mice and human trans-mitochondrial 'cybrid' (cytoplasmic hybrid) neuronal cells, whose mitochondria are derived from platelets of patients with sporadic AD- or mild cognitive impairment (MCI)-derived mitochondria. Increased formation of tau oligomers correlates with elevated ROS levels in the hippocampi of AD patients and tauopathy mice, AD- and MCI-derived mitochondria and AD and MCI cybrid cells. Furthermore, scavenging ROS by application of mito-TEMPO/2-(2,2,6,6-Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride, a mitochondria-targeted antioxidant, not only inhibits the generation of mitochondrial ROS and rescues mitochondrial respiratory function but also robustly suppresses tau oligomer accumulation in MCI and AD cybrids as well as cortical neurons from tau mice. These studies provide substantial evidence that mitochondria-mediated oxidative stress contributes to tau oligomer formation and accumulation.


Asunto(s)
Enfermedad de Alzheimer , Tauopatías , Enfermedad de Alzheimer/patología , Animales , Humanos , Ratones , Mitocondrias/metabolismo , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Tauopatías/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
18.
Oncologist ; 29(1): e15-e24, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37279780

RESUMEN

BACKGROUND: Neoadjuvant trastuzumab/pertuzumab (HP) plus chemotherapy for HER2-positive breast cancer (BC) achieved promising efficacy. The additional cardiotoxicity still existed. Brecan study evaluated the efficacy and safety of neoadjuvant pegylated liposomal doxorubicin (PLD)/cyclophosphamide and sequential nab-paclitaxel based on HP (PLD/C/HP-nabP/HP). PATIENTS AND METHODS: Brecan was a single-arm phase II study. Eligible patients with stages IIA-IIIC HER2-positive BC received 4 cycles of PLD, cyclophosphamide, and HP, followed by 4 cycles of nab-paclitaxel and HP. Definitive surgery was scheduled after 21 days for patients completing treatment or experiencing intolerable toxicity. The primary endpoint was the pathological complete response (pCR). RESULTS: Between January 2020 and December 2021, 96 patients were enrolled. Ninety-five (99.0%) patients received 8 cycles of neoadjuvant therapy and all underwent surgery with 45 (46.9%) breast-conserving surgery and 51 (53.1%) mastectomy. The pCR was 80.2% (95%CI, 71.2%-87.0%). Four (4.2%) experienced left ventricular insufficiency with an absolute decline in LVEF (43%-49%). No congestive heart failure and ≥grade 3 cardiac toxicity occurred. The objective response rate was 85.4% (95%CI, 77.0%-91.1%), including 57 (59.4%) complete responses and 25 (26.0%) partial responses. The disease control rate was 99.0% (95%CI, 94.3%-99.8%). For overall safety, ≥grade 3 AEs occurred in 30 (31.3%) and mainly included neutropenia (30.2%) and asthenia (8.3%). No treatment-related deaths occurred. Notably, age of >30 (P = .01; OR = 5.086; 95%CI, 1.44-17.965) and HER2 IHC 3+ (P = .02; OR = 4.398; 95%CI, 1.286-15.002) were independent predictors for superior pCR (ClinicalTrials.gov Identifier NCT05346107). CONCLUSION: Brecan study demonstrated the encouraging safety and efficacy of neoadjuvant PLD/C/HP-nabP/HP, suggesting a potential therapeutic option in HER2-positive BC.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Terapia Neoadyuvante/efectos adversos , Receptor ErbB-2/uso terapéutico , Mastectomía , Resultado del Tratamiento , Paclitaxel , Ciclofosfamida/uso terapéutico , Trastuzumab/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
19.
Anal Chem ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916969

RESUMEN

The integration of electrochemistry with nuclear magnetic resonance (NMR) spectroscopy recently offers a powerful approach to understanding oxidative metabolism, detecting reactive intermediates, and predicting biological activities. This combination is particularly effective as electrochemical methods provide excellent mimics of metabolic processes, while NMR spectroscopy offers precise chemical analysis. NMR is already widely utilized in the quality control of pharmaceuticals, foods, and additives and in metabolomic studies. However, the introduction of additional and external connections into the magnet has posed challenges, leading to signal deterioration and limitations in routine measurements. Herein, we report an anti-interference compact in situ electrochemical NMR system (AICISENS). Through a wireless strategy, the compact design allows for the independent and stable operation of electrochemical NMR components with effective interference isolation. Thus, it opens an avenue toward easy integration into in situ platforms, applicable not only to laboratory settings but also to fieldwork. The operability, reliability, and versatility were validated with a series of biomimetic assessments, including measurements of microbial electrochemical systems, functional foods, and simulated drug metabolisms. The robust performance of AICISENS demonstrates its high potential as a powerful analytical tool across diverse applications.

20.
Am J Physiol Heart Circ Physiol ; 327(1): H56-H66, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38758128

RESUMEN

Mouse models of congenital aortic valve malformations are useful for studying disease pathobiology, but most models have incomplete penetrance [e.g., ∼2 to 77% prevalence of bicuspid aortic valves (BAVs) across multiple models]. For longitudinal studies of pathologies associated with BAVs and other congenital valve malformations, which manifest over months in mice, it is operationally inefficient, economically burdensome, and ethically challenging to enroll large numbers of mice in studies without first identifying those with valvular abnormalities. To address this need, we established and validated a novel in vivo high-frequency (30 MHz) ultrasound imaging protocol capable of detecting aortic valvular malformations in juvenile mice. Fifty natriuretic peptide receptor 2 heterozygous mice on a low-density lipoprotein receptor-deficient background (Npr2+/-;Ldlr-/-; 32 males and 18 females) were imaged at 4 and 8 wk of age. Fourteen percent of the Npr2+/-;Ldlr-/- mice exhibited features associated with aortic valve malformations, including 1) abnormal transaortic flow patterns on color Doppler (recirculation and regurgitation), 2) peak systolic flow velocities distal to the aortic valves reaching or surpassing ∼1,250 mm/s by pulsed-wave Doppler, and 3) putative fusion of cusps along commissures and abnormal movement elucidated by two-dimensional (2-D) imaging with ultrahigh temporal resolution. Valves with these features were confirmed by ex vivo gross anatomy and histological visualization to have thickened cusps, partial fusions, or Sievers type-0 bicuspid valves. This ultrasound imaging protocol will enable efficient, cost effective, and humane implementation of studies of congenital aortic valvular abnormalities and associated pathologies in a wide range of mouse models.NEW & NOTEWORTHY We developed a high-frequency ultrasound imaging protocol for diagnosing congenital aortic valve structural abnormalities in 4-wk-old mice. Our protocol defines specific criteria to distinguish mice with abnormal aortic valves from those with normal tricuspid valves using color Doppler, pulsed-wave Doppler, and two-dimensional (2-D) imaging with ultrahigh temporal resolution. This approach enables early identification of valvular abnormalities for efficient and ethical experimental design of longitudinal studies of congenital valve diseases and associated pathologies in mice.


Asunto(s)
Válvula Aórtica , Modelos Animales de Enfermedad , Receptores del Factor Natriurético Atrial , Animales , Válvula Aórtica/anomalías , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Femenino , Masculino , Receptores del Factor Natriurético Atrial/genética , Receptores del Factor Natriurético Atrial/deficiencia , Receptores del Factor Natriurético Atrial/metabolismo , Ratones , Ratones Noqueados , Receptores de LDL/genética , Receptores de LDL/deficiencia , Ratones Endogámicos C57BL , Enfermedad de la Válvula Aórtica Bicúspide/diagnóstico por imagen
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