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1.
Cell ; 187(9): 2305-2323.e33, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38614099

RESUMEN

Cancer immunotherapy has transformed treatment possibilities, but its effectiveness differs significantly among patients, indicating the presence of alternative pathways for immune evasion. Here, we show that ITPRIPL1 functions as an inhibitory ligand of CD3ε, and its expression inhibits T cells in the tumor microenvironment. The binding of ITPRIPL1 extracellular domain to CD3ε on T cells significantly decreased calcium influx and ZAP70 phosphorylation, impeding initial T cell activation. Treatment with a neutralizing antibody against ITPRIPL1 restrained tumor growth and promoted T cell infiltration in mouse models across various solid tumor types. The antibody targeting canine ITPRIPL1 exhibited notable therapeutic efficacy against naturally occurring tumors in pet clinics. These findings highlight the role of ITPRIPL1 (or CD3L1, CD3ε ligand 1) in impeding T cell activation during the critical "signal one" phase. This discovery positions ITPRIPL1 as a promising therapeutic target against multiple tumor types.


Asunto(s)
Complejo CD3 , Activación de Linfocitos , Linfocitos T , Escape del Tumor , Microambiente Tumoral , Animales , Complejo CD3/metabolismo , Complejo CD3/inmunología , Humanos , Ratones , Linfocitos T/inmunología , Linfocitos T/metabolismo , Microambiente Tumoral/inmunología , Perros , Neoplasias/inmunología , Línea Celular Tumoral , Femenino , Unión Proteica , Proteína Tirosina Quinasa ZAP-70/metabolismo , Anticuerpos Neutralizantes/inmunología , Ratones Endogámicos C57BL
2.
Nat Immunol ; 22(9): 1175-1185, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34429546

RESUMEN

Systematic characterizations of adipose regulatory T (Treg) cell subsets and their phenotypes remain uncommon. Using single-cell ATAC-sequencing and paired single-cell RNA and T cell receptor (TCR) sequencing to map mouse adipose Treg cells, we identified CD73hiST2lo and CD73loST2hi subsets with distinct clonal expansion patterns. Analysis of TCR-sharing data implied a state transition between CD73hiST2lo and CD73loST2hi subsets. Mechanistically, we revealed that insulin signaling occurs through a HIF-1α-Med23-PPAR-γ axis to drive the transition of CD73hiST2lo into a CD73loST2hi adipose Treg cell subset. Treg cells deficient in insulin receptor, HIF-1α or Med23 have decreased PPAR-γ expression that in turn promotes accumulation of CD73hiST2lo adipose Treg cells and physiological adenosine production to activate beige fat biogenesis. We therefore unveiled a developmental trajectory of adipose Treg cells and its dependence on insulin signaling. Our findings have implications for understanding the dynamics of adipose Treg cell subsets in aged and obese contexts.


Asunto(s)
Tejido Adiposo/inmunología , Resistencia a la Insulina/inmunología , Insulina/metabolismo , Receptor de Insulina/metabolismo , Linfocitos T Reguladores/inmunología , 5'-Nucleotidasa/genética , 5'-Nucleotidasa/metabolismo , Tejido Adiposo/citología , Envejecimiento/inmunología , Animales , Células Cultivadas , Secuenciación de Nucleótidos de Alto Rendimiento , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/genética , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Masculino , Complejo Mediador/metabolismo , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/inmunología , PPAR gamma/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Transducción de Señal/genética , Transducción de Señal/inmunología , Linfocitos T Reguladores/citología
3.
Cell ; 173(3): 634-648.e12, 2018 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-29606356

RESUMEN

Identifying tumor-induced leukocyte subsets and their derived circulating factors has been instrumental in understanding cancer as a systemic disease. Nevertheless, how primary tumor-induced non-leukocyte populations in distal organs contribute to systemic spread remains poorly defined. Here, we report one population of tumor-inducible, erythroblast-like cells (Ter-cells) deriving from megakaryocyte-erythroid progenitor cells with a unique Ter-119+CD45-CD71+ phenotype. Ter-cells are enriched in the enlarged spleen of hosts bearing advanced tumors and facilitate tumor progression by secreting neurotrophic factor artemin into the blood. Transforming growth factor ß (TGF-ß) and Smad3 activation are important in Ter-cell generation. In vivo blockade of Ter-cell-derived artemin inhibits hepatocellular carcinoma (HCC) growth, and artemin deficiency abolishes Ter-cells' tumor-promoting ability. We confirm the presence of splenic artemin-positive Ter-cells in human HCC patients and show that significantly elevated serum artemin correlates with poor prognosis. We propose that Ter-cells and the secreted artemin play important roles in cancer progression with prognostic and therapeutic implications.


Asunto(s)
Progresión de la Enfermedad , Eritroblastos/citología , Proteínas del Tejido Nervioso/sangre , Bazo/citología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Apoptosis , Carcinoma Hepatocelular/metabolismo , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Receptores del Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Células Hep G2 , Humanos , Antígenos Comunes de Leucocito/metabolismo , Leucocitos/citología , Neoplasias Hepáticas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Invasividad Neoplásica/genética , Transducción de Señal
5.
Nature ; 630(8015): 59-63, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750357

RESUMEN

Ab initio calculations have an essential role in our fundamental understanding of quantum many-body systems across many subfields, from strongly correlated fermions1-3 to quantum chemistry4-6 and from atomic and molecular systems7-9 to nuclear physics10-14. One of the primary challenges is to perform accurate calculations for systems where the interactions may be complicated and difficult for the chosen computational method to handle. Here we address the problem by introducing an approach called wavefunction matching. Wavefunction matching transforms the interaction between particles so that the wavefunctions up to some finite range match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible owing to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations15,16 of light nuclei, medium-mass nuclei, neutron matter and nuclear matter. We use high-fidelity chiral effective field theory interactions17,18 and find good agreement with empirical data. These results are accompanied by insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii and nuclear-matter saturation in ab initio calculations19,20.

6.
Nature ; 630(8016): 381-386, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811733

RESUMEN

Lignocellulose is mainly composed of hydrophobic lignin and hydrophilic polysaccharide polymers, contributing to an indispensable carbon resource for green biorefineries1,2. When chemically treated, lignin is compromised owing to detrimental intra- and intermolecular crosslinking that hampers downstream process3,4. The current valorization paradigms aim to avoid the formation of new C-C bonds, referred to as condensation, by blocking or stabilizing the vulnerable moieties of lignin5-7. Although there have been efforts to enhance biomass utilization through the incorporation of phenolic additives8,9, exploiting lignin's proclivity towards condensation remains unproven for valorizing both lignin and carbohydrates to high-value products. Here we leverage the proclivity by directing the C-C bond formation in a catalytic arylation pathway using lignin-derived phenols with high nucleophilicity. The selectively condensed lignin, isolated in near-quantitative yields while preserving its prominent cleavable ß-ether units, can be unlocked in a tandem catalytic process involving aryl migration and transfer hydrogenation. Lignin in wood is thereby converted to benign bisphenols (34-48 wt%) that represent performance-advantaged replacements for their fossil-based counterparts. Delignified pulp from cellulose and xylose from xylan are co-produced for textile fibres and renewable chemicals. This condensation-driven strategy represents a key advancement complementary to other promising monophenol-oriented approaches targeting valuable platform chemicals and materials, thereby contributing to holistic biomass valorization.


Asunto(s)
Compuestos de Bencidrilo , Biomasa , Fraccionamiento Químico , Lignina , Fenoles , Compuestos de Bencidrilo/química , Compuestos de Bencidrilo/metabolismo , Catálisis , Celulosa/química , Celulosa/metabolismo , Fraccionamiento Químico/métodos , Hidrogenación , Lignina/química , Lignina/metabolismo , Fenoles/química , Fenoles/metabolismo , Madera/química , Xilanos/química , Xilanos/metabolismo , Xilosa/química , Xilosa/metabolismo , Combustibles Fósiles , Textiles
7.
Nature ; 621(7979): 536-542, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37558870

RESUMEN

Coral reef ecosystems are being fundamentally restructured by local human impacts and climate-driven marine heatwaves that trigger mass coral bleaching and mortality1. Reducing local impacts can increase reef resistance to and recovery from bleaching2. However, resource managers lack clear advice on targeted actions that best support coral reefs under climate change3 and sector-based governance means most land- and sea-based management efforts remain siloed4. Here we combine surveys of reef change with a unique 20-year time series of land-sea human impacts that encompassed an unprecedented marine heatwave in Hawai'i. Reefs with increased herbivorous fish populations and reduced land-based impacts, such as wastewater pollution and urban runoff, had positive coral cover trajectories predisturbance. These reefs also experienced a modest reduction in coral mortality following severe heat stress compared to reefs with reduced fish populations and enhanced land-based impacts. Scenario modelling indicated that simultaneously reducing land-sea human impacts results in a three- to sixfold greater probability of a reef having high reef-builder cover four years postdisturbance than if either occurred in isolation. International efforts to protect 30% of Earth's land and ocean ecosystems by 2030 are underway5. Our results reveal that integrated land-sea management could help achieve coastal ocean conservation goals and provide coral reefs with the best opportunity to persist in our changing climate.


Asunto(s)
Antozoos , Conservación de los Recursos Naturales , Arrecifes de Coral , Calor Extremo , Calentamiento Global , Océanos y Mares , Agua de Mar , Animales , Conservación de los Recursos Naturales/métodos , Calor Extremo/efectos adversos , Peces , Calentamiento Global/estadística & datos numéricos , Objetivos , Hawaii , Actividades Humanas , Cooperación Internacional , Agua de Mar/análisis , Agua de Mar/química , Aguas Residuales/análisis , Factores de Tiempo
8.
Nature ; 620(7975): 881-889, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37558878

RESUMEN

Dendritic cells (DCs) have a role in the development and activation of self-reactive pathogenic T cells1,2. Genetic variants that are associated with the function of DCs have been linked to autoimmune disorders3,4, and DCs are therefore attractive therapeutic targets for such diseases. However, developing DC-targeted therapies for autoimmunity requires identification of the mechanisms that regulate DC function. Here, using single-cell and bulk transcriptional and metabolic analyses in combination with cell-specific gene perturbation studies, we identify a regulatory loop of negative feedback that operates in DCs to limit immunopathology. Specifically, we find that lactate, produced by activated DCs and other immune cells, boosts the expression of NDUFA4L2 through a mechanism mediated by hypoxia-inducible factor 1α (HIF-1α). NDUFA4L2 limits the production of mitochondrial reactive oxygen species that activate XBP1-driven transcriptional modules in DCs that are involved in the control of pathogenic autoimmune T cells. We also engineer a probiotic that produces lactate and suppresses T cell autoimmunity through the activation of HIF-1α-NDUFA4L2 signalling in DCs. In summary, we identify an immunometabolic pathway that regulates DC function, and develop a synthetic probiotic for its therapeutic activation.


Asunto(s)
Enfermedades Autoinmunes , Sistema Nervioso Central , Células Dendríticas , Subunidad alfa del Factor 1 Inducible por Hipoxia , Ácido Láctico , Humanos , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Enfermedades Autoinmunes/prevención & control , Autoinmunidad , Sistema Nervioso Central/citología , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/patología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/química , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ácido Láctico/metabolismo , Probióticos/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Linfocitos T/inmunología , Retroalimentación Fisiológica , Lactasa/genética , Lactasa/metabolismo , Análisis de la Célula Individual
9.
Nature ; 605(7908): 160-165, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35477756

RESUMEN

Colorectal cancer (CRC) is among the most frequent forms of cancer, and new strategies for its prevention and therapy are urgently needed1. Here we identify a metabolite signalling pathway that provides actionable insights towards this goal. We perform a dietary screen in autochthonous animal models of CRC and find that ketogenic diets exhibit a strong tumour-inhibitory effect. These properties of ketogenic diets are recapitulated by the ketone body ß-hydroxybutyrate (BHB), which reduces the proliferation of colonic crypt cells and potently suppresses intestinal tumour growth. We find that BHB acts through the surface receptor Hcar2 and induces the transcriptional regulator Hopx, thereby altering gene expression and inhibiting cell proliferation. Cancer organoid assays and single-cell RNA sequencing of biopsies from patients with CRC provide evidence that elevated BHB levels and active HOPX are associated with reduced intestinal epithelial proliferation in humans. This study thus identifies a BHB-triggered pathway regulating intestinal tumorigenesis and indicates that oral or systemic interventions with a single metabolite may complement current prevention and treatment strategies for CRC.


Asunto(s)
Neoplasias Colorrectales , Transducción de Señal , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacología , Animales , Proliferación Celular , Transformación Celular Neoplásica , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/prevención & control , Humanos
10.
EMBO J ; 42(6): e111473, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36719036

RESUMEN

BRD4 is a well-recognized transcriptional activator, but how it regulates gene transcriptional repression in a cell type-specific manner has remained elusive. In this study, we report that BRD4 works with Polycomb repressive complex 2 (PRC2) to repress transcriptional expression of the T-helper 2 (Th2)-negative regulators Foxp3 and E3-ubiqutin ligase Fbxw7 during lineage-specific differentiation of Th2 cells from mouse primary naïve CD4+ T cells. Brd4 binds to the lysine-acetylated-EED subunit of the PRC2 complex via its second bromodomain (BD2) to facilitate histone H3 lysine 27 trimethylation (H3K27me3) at target gene loci and thereby transcriptional repression. We found that Foxp3 represses transcription of Th2-specific transcription factor Gata3, while Fbxw7 promotes its ubiquitination-directed protein degradation. BRD4-mediated repression of Foxp3 and Fbxw7 in turn promotes BRD4- and Gata3-mediated transcriptional activation of Th2 cytokines including Il4, Il5, and Il13. Chemical inhibition of the BRD4 BD2 induces transcriptional de-repression of Foxp3 and Fbxw7, and thus transcriptional downregulation of Il4, Il5, and Il13, resulting in inhibition of Th2 cell lineage differentiation. Our study presents a previously unappreciated mechanism of BRD4's role in orchestrating a Th2-specific transcriptional program that coordinates gene repression and activation, and safeguards cell lineage differentiation.


Asunto(s)
Proteínas Nucleares , Complejo Represivo Polycomb 2 , Ratones , Animales , Complejo Represivo Polycomb 2/metabolismo , Proteínas Nucleares/metabolismo , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Interleucina-13/metabolismo , Interleucina-4/genética , Interleucina-5/metabolismo , Lisina , Diferenciación Celular/genética , Factores de Transcripción Forkhead/genética
11.
Nature ; 599(7885): 399-403, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34789901

RESUMEN

The breakdown of translational symmetry at heterointerfaces leads to the emergence of new phonon modes localized at the interface1. These modes have an essential role in thermal and electrical transport properties in devices, especially in miniature ones wherein the interface may dominate the entire response of the device2. Although related theoretical work began decades ago1,3-5, experimental research is totally absent owing to challenges in achieving the combined spatial, momentum and spectral resolutions required to probe localized modes. Here, using the four-dimensional electron energy-loss spectroscopy technique, we directly measure both the local vibrational spectra and the interface phonon dispersion relation for an epitaxial cubic boron nitride/diamond heterointerface. In addition to bulk phonon modes, we observe modes localized at the interface and modes isolated from the interface. These features appear only within approximately one nanometre around the interface. The localized modes observed here are predicted to substantially affect the interface thermal conductance and electron mobility. Our findings provide insights into lattice dynamics at heterointerfaces, and the demonstrated experimental technique should be useful in thermal management, electrical engineering and topological phononics.

12.
Nature ; 598(7882): 662-666, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34616044

RESUMEN

The availability of L-arginine in tumours is a key determinant of an efficient anti-tumour T cell response1-4. Consequently, increases of typically low L-arginine concentrations within the tumour may greatly potentiate the anti-tumour responses of immune checkpoint inhibitors, such as programmed death-ligand 1 (PD-L1)-blocking antibodies5. However, currently no means are available to locally increase intratumoural L-arginine levels. Here we used a synthetic biology approach to develop an engineered probiotic Escherichia coli Nissle 1917 strain that colonizes tumours and continuously converts ammonia, a metabolic waste product that accumulates in tumours6, to L-arginine. Colonization of tumours with these bacteria increased intratumoural L-arginine concentrations, increased the number of tumour-infiltrating T cells and had marked synergistic effects with PD-L1 blocking antibodies in the clearance of tumours. The anti-tumour effect of these bacteria was mediated by L-arginine and was dependent on T cells. These results show that engineered microbial therapies enable metabolic modulation of the tumour microenvironment leading to enhanced efficacy of immunotherapies.


Asunto(s)
Inmunoterapia/métodos , Ingeniería Metabólica , Microorganismos Modificados Genéticamente , Neoplasias Experimentales/terapia , Traslado Adoptivo , Animales , Arginina/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Línea Celular Tumoral , Escherichia coli , Femenino , Linfocitos Infiltrantes de Tumor/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/microbiología , Probióticos , Proteoma , Biología Sintética , Linfocitos T/inmunología , Microambiente Tumoral/inmunología
13.
Nature ; 600(7890): 727-730, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34912120

RESUMEN

Human epidermal growth factor receptor 2 (HER2, also known as ERBB2) amplification or overexpression occurs in approximately 20% of advanced gastric or gastro-oesophageal junction adenocarcinomas1-3. More than a decade ago, combination therapy with the anti-HER2 antibody trastuzumab and chemotherapy became the standard first-line treatment for patients with these types of tumours4. Although adding the anti-programmed death 1 (PD-1) antibody pembrolizumab to chemotherapy does not significantly improve efficacy in advanced HER2-negative gastric cancer5, there are preclinical6-19 and clinical20,21 rationales for adding pembrolizumab in HER2-positive disease. Here we describe results of the protocol-specified first interim analysis of the randomized, double-blind, placebo-controlled phase III KEYNOTE-811 study of pembrolizumab plus trastuzumab and chemotherapy for unresectable or metastatic, HER2-positive gastric or gastro-oesophageal junction adenocarcinoma22 ( https://clinicaltrials.gov , NCT03615326). We show that adding pembrolizumab to trastuzumab and chemotherapy markedly reduces tumour size, induces complete responses in some participants, and significantly improves objective response rate.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Receptor de Muerte Celular Programada 1 , Receptor ErbB-2 , Neoplasias Gástricas , Trastuzumab , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Unión Esofagogástrica/efectos de los fármacos , Unión Esofagogástrica/patología , Humanos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Trastuzumab/farmacología , Trastuzumab/uso terapéutico
14.
Proc Natl Acad Sci U S A ; 121(24): e2321267121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38838014

RESUMEN

Mitochondria perform an array of functions, many of which involve interactions with gene products encoded by the nucleus. These mitochondrial functions, particularly those involving energy production, can be expected to differ between sexes and across ages. Here, we measured mitochondrial effects on sex- and age-specific gene expression in parental and reciprocal F1 hybrids between allopatric populations of Tigriopus californicus with over 20% mitochondrial DNA divergence. Because the species lacks sex chromosomes, sex-biased mitochondrial effects are not confounded by the effects of sex chromosomes. Results revealed pervasive sex differences in mitochondrial effects, including effects on energetics and aging involving nuclear interactions throughout the genome. Using single-individual RNA sequencing, sex differences were found to explain more than 80% of the variance in gene expression. Males had higher expression of mitochondrial genes and mitochondrially targeted proteins (MTPs) involved in oxidative phosphorylation (OXPHOS), while females had elevated expression of non-OXPHOS MTPs, indicating strongly sex-dimorphic energy metabolism at the whole organism level. Comparison of reciprocal F1 hybrids allowed insights into the nature of mito-nuclear interactions, showing both mitochondrial effects on nuclear expression, and nuclear effects on mitochondrial expression. While based on a small set of crosses, sex-specific increases in mitochondrial expression with age were associated with longer life. Network analyses identified nuclear components of strong mito-nuclear interactions and found them to be sexually dimorphic. These results highlight the profound impact of mitochondria and mito-nuclear interactions on sex- and age-specific gene expression.


Asunto(s)
Mitocondrias , Cromosomas Sexuales , Animales , Femenino , Masculino , Mitocondrias/genética , Mitocondrias/metabolismo , Cromosomas Sexuales/genética , Envejecimiento/genética , Envejecimiento/metabolismo , Fosforilación Oxidativa , Caracteres Sexuales , ADN Mitocondrial/genética , Núcleo Celular/metabolismo , Núcleo Celular/genética , Regulación de la Expresión Génica , Metabolismo Energético/genética
15.
Chem Rev ; 124(6): 2889-2954, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38483065

RESUMEN

In recent years, the issues of global warming and CO2 emission reduction have garnered increasing global attention. In the 21st Conference of the Parties (convened in Paris in 2015), 179 nations and the European Union signed a pivotal agreement to limit the global temperature increase of this century to well below 2 K above preindustrial levels. To fulfill this objective, extensive research has been conducted to use renewable energy sources as potential replacements for traditional fossil fuels. Among them, the production of hydrocarbon transportation fuels from CO2-neutral and renewable biomass has proven to be a particularly promising solution due to its compatibility with existing infrastructure. This review systematically summarizes research progress in the synthesis of liquid hydrocarbon biofuels from lignocellulose during the past two decades. Based on the chemical structure (including n-paraffins, iso-paraffins, aromatics, and cycloalkanes) of hydrocarbon transportation fuels, the synthesis pathways of these biofuels are discussed in four separate sections. Furthermore, this review proposes three guiding principles for the design of practical hydrocarbon biofuels, providing insights into future directions for the development of viable biomass-derived liquid fuels.

16.
Cell ; 147(1): 173-84, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-21962514

RESUMEN

Saturated fatty acids (FA) exert adverse health effects and are more likely to cause insulin resistance and type 2 diabetes than unsaturated FA, some of which exert protective and beneficial effects. Saturated FA, but not unsaturated FA, activate Jun N-terminal kinase (JNK), which has been linked to obesity and insulin resistance in mice and humans. However, it is unknown how saturated and unsaturated FA are discriminated. We now demonstrate that saturated FA activate JNK and inhibit insulin signaling through c-Src activation. FA alter the membrane distribution of c-Src, causing it to partition into intracellular membrane subdomains, where it likely becomes activated. Conversely, unsaturated FA with known beneficial effects on glucose metabolism prevent c-Src membrane partitioning and activation, which are dependent on its myristoylation, and block JNK activation. Consumption of a diabetogenic high-fat diet causes the partitioning and activation of c-Src within detergent insoluble membrane subdomains of murine adipocytes.


Asunto(s)
Adipocitos/metabolismo , Ácidos Grasos/metabolismo , Resistencia a la Insulina , Membranas Intracelulares/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Adipocitos/química , Animales , Diabetes Mellitus Tipo 2/metabolismo , Dieta , Ácidos Grasos Insaturados/metabolismo , Fibroblastos/metabolismo , Ratones , Ratones Endogámicos C57BL , Obesidad/metabolismo , Proteínas Proto-Oncogénicas pp60(c-src)/análisis , Transducción de Señal
17.
Mol Cell Proteomics ; 23(3): 100738, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38364992

RESUMEN

Wind is one of the most prevalent environmental forces entraining plants to develop various mechano-responses, collectively called thigmomorphogenesis. Largely unknown is how plants transduce these versatile wind force signals downstream to nuclear events and to the development of thigmomorphogenic phenotype or anemotropic response. To identify molecular components at the early steps of the wind force signaling, two mechanical signaling-related phosphoproteins, identified from our previous phosphoproteomic study of Arabidopsis touch response, mitogen-activated protein kinase kinase 1 (MKK1) and 2 (MKK2), were selected for performing in planta TurboID (ID)-based quantitative proximity-labeling (PL) proteomics. This quantitative biotinylproteomics was separately performed on MKK1-ID and MKK2-ID transgenic plants, respectively, using the genetically engineered TurboID biotin ligase expression transgenics as a universal control. This unique PTM proteomics successfully identified 11 and 71 MKK1 and MKK2 putative interactors, respectively. Biotin occupancy ratio (BOR) was found to be an alternative parameter to measure the extent of proximity and specificity between the proximal target proteins and the bait fusion protein. Bioinformatics analysis of these biotinylprotein data also found that TurboID biotin ligase favorably labels the loop region of target proteins. A WInd-Related Kinase 1 (WIRK1), previously known as rapidly accelerated fibrosarcoma (Raf)-like kinase 36 (RAF36), was found to be a putative common interactor for both MKK1 and MKK2 and preferentially interacts with MKK2. Further molecular biology studies of the Arabidopsis RAF36 kinase found that it plays a role in wind regulation of the touch-responsive TCH3 and CML38 gene expression and the phosphorylation of a touch-regulated PATL3 phosphoprotein. Measurement of leaf morphology and shoot gravitropic response of wirk1 (raf36) mutant revealed that the WIRK1 gene is involved in both wind-triggered rosette thigmomorphogenesis and gravitropism of Arabidopsis stems, suggesting that the WIRK1 (RAF36) protein probably functioning upstream of both MKK1 and MKK2 and that it may serve as the crosstalk point among multiple mechano-signal transduction pathways mediating both wind mechano-response and gravitropism.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Gravitropismo , Biotina/metabolismo , Viento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Ligasas/metabolismo , Calmodulina/metabolismo
18.
Nucleic Acids Res ; 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38908023

RESUMEN

The concomitant cloning of RNA degradation products is a major concern in standard small RNA-sequencing practices. This not only complicates the characterization of bona fide sRNAs but also hampers cross-batch experimental replicability and sometimes even results in library construction failure. Given that all types of plant canonical small RNAs possess the 3' end 2'-O-methylation modification, a new small RNA sequencing (sRNA-seq) method, designated as PBOX-sRNA-seq, has been developed specifically to capture this modification. PBOX-sRNA-seq, as its name implies, relies on the sequential treatment of RNA samples with phenylboronic acid-polyacrylamide gel electrophoresis (PBA-PAGE) and sodium periodate (NaIO4) oxidation, before sRNA library construction and sequencing. PBOX-sRNA-seq outperformed separate treatments (i.e. PBA-PAGE only or NaIO4 only) in terms of the depletion of unmethylated RNA species and capture 2'-O-modified sRNAs with extra-high purity. Using PBOX-sRNA-seq, we discovered that nascent miRNA-5p/-3p duplexes may undergo mono-cytidylation/uridylation before 2'-O-methylation. We also identified two highly conserved types of 5'-tRNA fragments (tRF) bearing HEN1-independent 2'-O modification (mainly the 13-nt tRF-5aAla and the 26-nt tRF-5bGly). We believe that PBOX-sRNA-seq is powerful for both qualitative and quantitative analyses of sRNAs in plants and piRNAs in animals.

19.
Proc Natl Acad Sci U S A ; 120(40): e2310881120, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37748065

RESUMEN

Cytonuclear disruption may accompany allopolyploid evolution as a consequence of the merger of different nuclear genomes in a cellular environment having only one set of progenitor organellar genomes. One path to reconcile potential cytonuclear mismatch is biased expression for maternal gene duplicates (homoeologs) encoding proteins that target to plastids and/or mitochondria. Assessment of this transcriptional form of cytonuclear coevolution at the level of individual cells or cell types remains unexplored. Using single-cell (sc-) and single-nucleus (sn-) RNAseq data from eight tissues in three allopolyploid species, we characterized cell type-specific variations of cytonuclear coevolutionary homoeologous expression and demonstrated the temporal dynamics of expression patterns across development stages during cotton fiber development. Our results provide unique insights into transcriptional cytonuclear coevolution in plant allopolyploids at the single-cell level.


Asunto(s)
Mitocondrias , Plastidios , Mitocondrias/genética , Diferenciación Celular , Núcleo Solitario
20.
Brief Bioinform ; 24(3)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37080761

RESUMEN

Advancing spatially resolved transcriptomics (ST) technologies help biologists comprehensively understand organ function and tissue microenvironment. Accurate spatial domain identification is the foundation for delineating genome heterogeneity and cellular interaction. Motivated by this perspective, a graph deep learning (GDL) based spatial clustering approach is constructed in this paper. First, the deep graph infomax module embedded with residual gated graph convolutional neural network is leveraged to address the gene expression profiles and spatial positions in ST. Then, the Bayesian Gaussian mixture model is applied to handle the latent embeddings to generate spatial domains. Designed experiments certify that the presented method is superior to other state-of-the-art GDL-enabled techniques on multiple ST datasets. The codes and dataset used in this manuscript are summarized at https://github.com/narutoten520/SCGDL.


Asunto(s)
Aprendizaje Profundo , Transcriptoma , Teorema de Bayes , Perfilación de la Expresión Génica , Comunicación Celular
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