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1.
Nat Immunol ; 16(11): 1142-52, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26414765

RESUMEN

Mitochondria need to be juxtaposed to phagosomes for the synergistic production of ample reactive oxygen species (ROS) in phagocytes to kill pathogens. However, how phagosomes transmit signals to recruit mitochondria has remained unclear. Here we found that the kinases Mst1 and Mst2 functioned to control ROS production by regulating mitochondrial trafficking and mitochondrion-phagosome juxtaposition. Mst1 and Mst2 activated the GTPase Rac to promote Toll-like receptor (TLR)-triggered assembly of the TRAF6-ECSIT complex that is required for the recruitment of mitochondria to phagosomes. Inactive forms of Rac, including the human Rac2(D57N) mutant, disrupted the TRAF6-ECSIT complex by sequestering TRAF6 and substantially diminished ROS production and enhanced susceptibility to bacterial infection. Our findings demonstrate that the TLR-Mst1-Mst2-Rac signaling axis is critical for effective phagosome-mitochondrion function and bactericidal activity.


Asunto(s)
Fagocitos/inmunología , Fagocitos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Infecciones Bacterianas/etiología , Infecciones Bacterianas/inmunología , Infecciones Bacterianas/metabolismo , Actividad Bactericida de la Sangre/inmunología , Línea Celular , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Antígenos de Histocompatibilidad Menor , Mitocondrias/inmunología , Mitocondrias/metabolismo , Mitocondrias/microbiología , Fagocitos/microbiología , Fagosomas/inmunología , Fagosomas/metabolismo , Fagosomas/microbiología , Proteína Quinasa C-alfa/metabolismo , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/genética , Sepsis/etiología , Sepsis/inmunología , Sepsis/metabolismo , Serina-Treonina Quinasa 3 , Transducción de Señal , Factor 6 Asociado a Receptor de TNF , Receptores Toll-Like/metabolismo , Ubiquitinación , Proteínas de Unión al GTP rac/genética , Proteínas de Unión al GTP rac/metabolismo , Inhibidor beta de Disociación del Nucleótido Guanina rho/metabolismo
2.
J Immunol ; 212(3): 397-409, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38088801

RESUMEN

SHP-1 (Src homology region 2 domain-containing phosphatase 1) is a well-known negative regulator of T cells, whereas its close homolog SHP-2 is the long-recognized main signaling mediator of the PD-1 inhibitory pathway. However, recent studies have challenged the requirement of SHP-2 in PD-1 signaling, and follow-up studies further questioned the alternative idea that SHP-1 may replace SHP-2 in its absence. In this study, we systematically investigate the role of SHP-1 alone or jointly with SHP-2 in CD8+ T cells in a series of gene knockout mice. We show that although SHP-1 negatively regulates CD8+ T cell effector function during acute lymphocytic choriomeningitis virus (LCMV) infection, it is dispensable for CD8+ T cell exhaustion during chronic LCMV infection. Moreover, in contrast to the mortality of PD-1 knockout mice upon chronic LCMV infection, mice double deficient for SHP-1 and SHP-2 in CD8+ T cells survived without immunopathology. Importantly, CD8+ T cells lacking both phosphatases still differentiate into exhausted cells and respond to PD-1 blockade. Finally, we found that SHP-1 and SHP-2 suppressed effector CD8+ T cell expansion at the early and late stages, respectively, during chronic LCMV infection.


Asunto(s)
Coriomeningitis Linfocítica , Virus de la Coriomeningitis Linfocítica , Animales , Ratones , Linfocitos T CD8-positivos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor de Muerte Celular Programada 1/metabolismo , Agotamiento de Células T
3.
Chemistry ; 29(48): e202301121, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37300353

RESUMEN

Lithium-sulfur (Li-S) batteries are a promising energy storage technology due to their tempting high theoretical capacity and energy density. Nevertheless, the wastage of active materials that originates from the shuttling effect of polysulfides still hinders advancement of Li-S batteries. The effective design of cathode materials is extremely pivotal to solve this thorny problem. Herein, surface engineering in covalent organic polymers (COPs) has been performed to investigate the influence of pore wall polarity on the performance of COP-based cathodes used for Li-S batteries. With the assistance of experimental investigation and theoretical calculations, performance improvement by increasing pore surface polarity and a synergy effect of the polarized functionalities, along with nano-confinement effect of the COPs, are disclosed, to which the improved performance of Li-S batteries including outstanding Coulombic efficiency (99.0 %) and extremely low capacity decay (0.08 % over 425 cycles at 1.0 C) is attributed. This work not only enlightens the designable synthesis and applications of covalent polymers as polar sulfur hosts with high utilization of active materials, but also provides a feasible guide for the design of effective cathode materials for future advanced Li-S batteries.

4.
J Proteome Res ; 21(2): 507-518, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-34969243

RESUMEN

Targeted analysis of data-independent acquisition (DIA) data needs a spectral library, which is generated by data-dependent acquisition (DDA) experiments or directly from DIA data. A comparison of the DDA library and DIA library in analyzing DIA data has been reported. However, the effects of different spectral libraries on the analysis of diaPASEF data have not been investigated. Here, we generate different spectral libraries with varying proteome coverage to analyze parallel accumulation-serial fragmentation (diaPASEF) data. Besides, we also employ the library-free strategy. The library, constructed by extensive fractionation DDA experiments, produces the highest numbers of precursors and proteins but with a high percentage of missing values. The library-free strategy identifies 10-20% fewer proteins than the library-based method but with a high degree of data completeness. A further study shows that the library-free strategy, although it identifies fewer proteins than the library-based method, leads to similar biological conclusions as the library-based method.


Asunto(s)
Proteoma , Proteómica , Biblioteca de Péptidos , Proteómica/métodos
5.
Ecotoxicol Environ Saf ; 237: 113557, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35483149

RESUMEN

Mounting evidence has confirmed the existence of plant-soil feedback, a reflection of plant-soil interaction. However, analysis of ecological feedback pathways remains a challenge. In this study, single and mixed plant communities in different soil ecosystems were screened using strict control systems in global ecosystems to identify the positive or negative feedback effects in indicator plants. Furthermore, the plant components and biomass were identified in each pathway. The significantly changed components indicated pathway factors. As negative feedback increased, the InRR (Response Ratio) of soil organic matter, soil total N, microbial alpha diversity and the symbiotic fungi proportion were significantly up-regulated (P < 0.05). In contrast, the stoichiometric ratio (C: N), water content, and the pathogenic bacteria proportion were downregulated (P < 0.05). However, the positive feedback showed the opposite trend. Importantly, N limit as a transform node between positive and negative plant-soil feedback predicted by Akaike information criterion (AIC > 0.8). Therefore, it has become an important evaluation standard for the inter-species relationship and ecological environment changes under the background of global N deposition. Finally, the feedback values of each sampling site were recalculated over the next 20 years, 50 years, and 100 years based on the global temperature rise and changing rainfall patterns. We also found that global warming and extreme rainfall may change the distribution of interspecies relationships on a global scale, with global warming having the greatest recognisable effect and decreasing the negative feedback layout by 21.7% (P < 0.05). Therefore, this work promotes the cognition of relationship of soil environment, microbial abundance and function, plant diversity and plant- soil feedback model. Meanwhile, it is of great significance to protect species diversity and restore environmental degradation.


Asunto(s)
Micorrizas , Suelo , Biodiversidad , Ecosistema , Retroalimentación , Micorrizas/metabolismo , Nitrógeno/análisis , Plantas/metabolismo , Microbiología del Suelo , Temperatura
6.
FASEB J ; 34(6): 7631-7643, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32301540

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disorders which are characterized by the accumulation of excessive lipid in hepatocytes. The precise pathogenesis of NAFLD is very complicated and remains largely unknown. Smad ubiquitination regulatory factor 1 (Smurf1) is crucial for numerous processes including bone homeostasis, embryogenesis, and pathogenic autophagy. In this study, we found that liver steatosis was alleviated in Smurf1-deficient mice fed with high-fat diet (HFD) for 19 weeks. The deletion of Smurf1 reduced the accumulation of lipid droplets and triglycerides in hepatocytes. The stability of sterol regulatory element-binding protein-1c (SREBP-1c), a key transcription factor that mediates de novo lipogenesis, was markedly reduced in Smurf1-deficient mice. The mechanistic study showed that Smurf1 interacts with SREBP-1c and protects SREBP-1c from ubiquitination and degradation by preventing the binding of SREBP-1c to its ubiquitin E3 ligase Fbw7a. Thus, our study presented an E3 ligase catalytic activity-independent function of Smurf1 in the fatty liver development.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos/metabolismo , Células HEK293 , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Lípidos/fisiología , Lipogénesis/fisiología , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transcripción Genética/fisiología , Triglicéridos/metabolismo
7.
J Biol Chem ; 294(8): 2880-2891, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30587574

RESUMEN

Accumulating evidence indicates that a wide range of E3 ubiquitin ligases are involved in the development of many human diseases. Searching for small-molecule modulators of these E3 ubiquitin ligases is emerging as a promising drug discovery strategy. Here, we report the development of a cell-based high-throughput screening method to identify modulators of E3 ubiquitin ligases by integrating the ubiquitin-reference technique (URT), based on a fusion protein of ubiquitin located between a protein of interest and a reference protein moiety, with a Dual-Luciferase system. Using this method, we screened for small-molecule modulators of SMAD ubiquitin regulatory factor 1 (SMURF1), which belongs to the NEDD4 family of E3 ubiquitin ligases and is an attractive therapeutic target because of its roles in tumorigenesis. Using RAS homolog family member B (RHOB) as a SMURF1 substrate in this screen, we identified a potent SMURF1 inhibitor and confirmed that it also blocks SMURF1-dependent degradation of SMAD family member 1 (SMAD1) and RHOA. An in vitro auto-ubiquitination assay indicated that this compound inhibits both SMURF1 and SMURF2 activities, indicating that it may be an antagonist of the catalytic activity of the HECT domain in SMURF1/2. Moreover, cell functional assays revealed that this compound effectively inhibits protrusive activity in HEK293T cells and blocks transforming growth factor ß (TGFß)-induced epithelial-mesenchymal transition (EMT) in MDCK cells, similar to the effects on these processes caused by SMURF1 loss. In summary, the screening approach presented here may have great practical potential for identifying modulators of E3 ubiquitin ligases.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento/métodos , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina/metabolismo , Animales , Perros , Células HEK293 , Humanos , Células de Riñón Canino Madin Darby , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
8.
Int J Phytoremediation ; 22(10): 1085-1095, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32122163

RESUMEN

A laboratory experiment was performed to evaluate the potential role of H2S on cadmium (Cd) toxicity in Phlox paniculata L. Seeds pretreated with 0.3, 0.6, 0.9, and 1.2 mM NaHS as a donor of H2S for 24 h and subsequently exposed to 100, 200, and 300 µM CdCl2 for 26 days had significantly higher germination rate compared with Cd alone. Meanwhile, 2-year-old seedlings sprayed with 0.3, 0.6, and 0.9 µM NaHS were grown in soil with 0.3, 0.6, and 1.2 mg/kg CdCl2, respectively. We observed that H2S decreased Cd accumulation in leaves and elevated Cd concentration in roots. Cd toxicity in seedlings resulted in a substantial increase in Cd-induced overproduction of malondialdehyde (MDA), Cd accumulation, and electrolyte leakage. Meanwhile, addition of NaHS increased photosynthetic performance compared with Cd alone. Exogenous H2S significantly elevated biomass, improved antioxidant enzyme activities, and reduced ABA content compared with Cd alone. H2S also plays an important role in the ABA signaling pathway during stress. Notably, NaHS promoted Cd uptake by Phlox paniculate L. from soil. The prediction model of H2S for increasing plant resistance and reducing soil Cd pollution was established by factor analysis method based on comprehensive evaluation of plant stress physiology.


Asunto(s)
Sulfuro de Hidrógeno , Antioxidantes , Biodegradación Ambiental , Cadmio , Malondialdehído , Raíces de Plantas , Plantones
9.
Dev Cell ; 59(3): 384-399.e5, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38198890

RESUMEN

Different types of cells uptake fatty acids in response to different stimuli or physiological conditions; however, little is known about context-specific regulation of fatty acid uptake. Here, we show that muscle injury induces fatty acid uptake in muscle stem cells (MuSCs) to promote their proliferation and muscle regeneration. In humans and mice, fatty acids are mobilized after muscle injury. Through CD36, fatty acids function as both fuels and growth signals to promote MuSC proliferation. Mechanistically, injury triggers the translocation of CD36 in MuSCs, which relies on dynamic palmitoylation of STX11. Palmitoylation facilitates the formation of STX11/SNAP23/VAMP4 SANRE complex, which stimulates the fusion of CD36- and STX11-containing vesicles. Restricting fatty acid supply, blocking fatty acid uptake, or inhibiting STX11 palmitoylation attenuates muscle regeneration in mice. Our studies have identified a critical role of fatty acids in muscle regeneration and shed light on context-specific regulation of fatty acid sensing and uptake.


Asunto(s)
Ácidos Grasos , Lipoilación , Músculo Esquelético , Proteínas Qa-SNARE , Regeneración , Animales , Humanos , Ratones , Transporte Biológico , Antígenos CD36/metabolismo , Membrana Celular/metabolismo , Ácidos Grasos/metabolismo , Músculo Esquelético/lesiones , Músculo Esquelético/fisiología , Proteínas Qa-SNARE/metabolismo
10.
Adv Sci (Weinh) ; 10(18): e2300640, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37088735

RESUMEN

The scarcity of high electrocatalysis composite electrode materials has long been suppressing the redox reaction of V(II)/V(III) and V(IV)/V(V) couples in high performance vanadium redox flow batteries (VRFBs). Herein, through ingeniously regulating the growth of Aspergillus Niger, a wrinkle-like carbon (WLC) material that possesses edge-rich carbon, abundant heteroatoms, and nature wrinkle-like structure is obtained, which is subsequently successfully introduced and uniform dispersed on the surface of carbon fiber of graphite felt (GF). This composite electrode presents a lower overpotential and higher charge transfer ability, as the codoped multiheteroatoms increase the electrocatalysis activity and the wrinkled structure affords more abundant reaction area for vanadium ions in the electrolyte when compared with the pristine GF electrode, which is also supported by the density functional theory (DFT) calculations. Hence, the assembled battery using WLC electrodes achieves a high energy efficiency of 74.5% for 300 cycles at a high current density of 200 mA cm-2 , as well as the highest current density of 450 mA cm-2 . The WLC material not only uncovers huge potential in promoting the application of VRFBs, but also offers referential solution to synthesis microorganism-based high-performance electrode in other energy storage systems.


Asunto(s)
Carbono , Grafito , Carbono/química , Aspergillus niger , Vanadio/química , Grafito/química , Oxidación-Reducción , Electrodos
11.
World J Clin Cases ; 11(31): 7543-7552, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-38078121

RESUMEN

BACKGROUND: Deep vein thrombosis (DVT) of the lower extremity is one of the most common postoperative complications, especially after craniocerebral surgery. DVT may lead to pulmonary embolism, which has a devastating impact on patient prognosis. This study aimed to investigate the incidence and risk factors of DVT in the lower limbs following craniocerebral surgery. AIM: To identify independent risk factors for the development of postoperative DVT and to develop an effective risk prediction model. METHODS: The demographic and clinical data of 283 patients who underwent craniocerebral surgery between December 2021 and December 2022 were retrospectively analyzed. The independent risk factors for lower extremity DVT were identified by univariate and multivariate analyses. A nomogram was created to predict the likelihood of lower extremity DVT in patients who had undergone craniocerebral surgery. The efficacy of the prediction model was determined by receiver operating characteristic curve using the probability of lower extremity DVT for each sample. RESULTS: Among all patients included in the analysis, 47.7% developed lower extremity DVT following craniocerebral surgery. The risk of postoperative DVT was higher in those with a longer operative time, and patients with intraoperative intermittent pneumatic compression were less likely to develop postoperative DVT. CONCLUSION: The incidence of lower extremity DVT following craniocerebral surgery is significant, highlighting the importance of identifying independent risk factors. Interventions such as the use of intermittent pneumatic compression during surgery may prevent the formation of postoperative DVT.

12.
Imeta ; 2(4): e133, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38868220

RESUMEN

The prevalence of cadmium (Cd)-polluted agricultural soils is increasing globally, and arbuscular mycorrhizal fungi (AMF) can reduce the absorption of heavy metals by plants and improve mineral nutrition. However, the immobilization of the rhizosphere on cadmium is often overlooked. In this study, Glomus mosseae and Medicago sativa were established as symbiotes, and Cd migration and environmental properties in the rhizosphere were analyzed. AMF reduced Cd migration, and Cd2+ changed to an organic-bound state. AMF symbiosis treatment and Cd exposure resulted in microbial community variation, exhibiting a distinct deterministic process (|ßNTI| > 2), which ultimately resulted in a core microbiome function of heavy metal resistance and nutrient cycling. AMF increased available N and P, extracellular enzyme activity (LaC, LiP, and CAT), organic matter content (TOC, EOC, and GRSP), and Eh of the rhizosphere soil, significantly correlating with decreased Cd migration (p < 0.05). Furthermore, AMF significantly affected root metabolism by upregulating 739 metabolites, with flavonoids being the main factor causing microbiome variation. The structural equation model and variance partial analysis revealed that the superposition of the root metabolites, microbial, and soil exhibited the maximum explanation rate for Cd migration reduction (42.4%), and the microbial model had the highest single explanation rate (15.5%). Thus, the AMF in the rhizosphere microenvironment can regulate metabolite-soil-microbial interactions, reducing Cd migration. In summary, the study provides a new scientific explanation for how AMF improves plant Cd tolerance and offers a sustainable solution that could benefit both the environment and human health.

13.
Nat Commun ; 14(1): 2342, 2023 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-37095176

RESUMEN

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with poor outcome and lacks of approved targeted therapy. Overexpression of epidermal growth factor receptor (EGFR) is found in more than 50% TNBC and is suggested as a driving force in progression of TNBC; however, targeting EGFR using antibodies to prevent its dimerization and activation shows no significant benefits for TNBC patients. Here we report that EGFR monomer may activate signal transducer activator of transcription-3 (STAT3) in the absence of transmembrane protein TMEM25, whose expression is frequently decreased in human TNBC. Deficiency of TMEM25 allows EGFR monomer to phosphorylate STAT3 independent of ligand binding, and thus enhances basal STAT3 activation to promote TNBC progression in female mice. Moreover, supplying TMEM25 by adeno-associated virus strongly suppresses STAT3 activation and TNBC progression. Hence, our study reveals a role of monomeric-EGFR/STAT3 signaling pathway in TNBC progression and points out a potential targeted therapy for TNBC.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Animales , Ratones , Neoplasias de la Mama Triple Negativas/metabolismo , Receptores ErbB/metabolismo , Transducción de Señal/fisiología , Línea Celular Tumoral , Factor de Transcripción STAT3/metabolismo , Proliferación Celular/fisiología
14.
Cell Mol Immunol ; 20(5): 512-524, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36977779

RESUMEN

CD8+ T cells play a central role in antiviral immune responses. Upon infection, naive CD8+ T cells differentiate into effector cells to eliminate virus-infected cells, and some of these effector cells further differentiate into memory cells to provide long-term protection after infection is resolved. Although extensively investigated, the underlying mechanisms of CD8+ T-cell differentiation remain incompletely understood. Themis is a T-cell-specific protein that plays critical roles in T-cell development. Recent studies using Themis T-cell conditional knockout mice also demonstrated that Themis is required to promote mature CD8+ T-cell homeostasis, cytokine responsiveness, and antibacterial responses. In this study, we used LCMV Armstrong infection as a probe to explore the role of Themis in viral infection. We found that preexisting CD8+ T-cell homeostasis defects and cytokine hyporesponsiveness do not impair viral clearance in Themis T-cell conditional knockout mice. Further analyses showed that in the primary immune response, Themis deficiency promoted the differentiation of CD8+ effector cells and increased their TNF and IFNγ production. Moreover, Themis deficiency impaired memory precursor cell (MPEC) differentiation but promoted short-lived effector cell (SLEC) differentiation. Themis deficiency also enhanced effector cytokine production in memory CD8+ T cells while impairing central memory CD8+ T-cell formation. Mechanistically, we found that Themis mediates PD-1 expression and its signaling in effector CD8+ T cells, which explains the elevated cytokine production in these cells when Themis is disrupted.


Asunto(s)
Linfocitos T CD8-positivos , Coriomeningitis Linfocítica , Ratones , Animales , Virus de la Coriomeningitis Linfocítica , Diferenciación Celular , Citocinas/metabolismo , Ratones Noqueados , Ratones Endogámicos C57BL , Memoria Inmunológica , Péptidos y Proteínas de Señalización Intercelular/metabolismo
15.
J Biol Chem ; 286(18): 15883-94, 2011 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-21454478

RESUMEN

The transforming growth factor-ß (TGF-ß) superfamily of ligands signals along two intracellular pathways, Smad2/3-mediated TGF-ß/activin pathway and Smad1/5/8-mediated bone morphogenetic protein pathway. The C terminus of Hsc70-interacting protein (CHIP) serves as an E3 ubiquitin ligase to mediate the degradation of Smad proteins and many other signaling proteins. However, the molecular mechanism for CHIP-mediated down-regulation of TGF-ß signaling remains unclear. Here we show that the extreme C-terminal sequence of Smad1 plays an indispensable role in its direct association with the tetratricopeptide repeat (TPR) domain of CHIP. Interestingly, Smad1 undergoes CHIP-mediated polyubiquitination in the absence of molecular chaperones, and phosphorylation of the C-terminal SXS motif of Smad1 enhances the interaction and ubiquitination. We also found that CHIP preferentially binds to Smad1/5 and specifically disrupts the core signaling complex of Smad1/5 and Smad4. We determined the crystal structures of CHIP-TPR in complex with the phosphorylated/pseudophosphorylated Smad1 peptides and with an Hsp70/Hsc70 C-terminal peptide. Structural analyses and subsequent biochemical studies revealed that the distinct CHIP binding affinities of Smad1/5 or Smad2/3 result from the nonconservative hydrophobic residues at R-Smad C termini. Unexpectedly, the C-terminal peptides from Smad1 and Hsp70/Hsc70 bind in the same groove of CHIP-TPR, and heat shock proteins compete with Smad1/5 for CHIP interaction and concomitantly suppress, rather than facilitate, CHIP-mediated Smad ubiquitination. Thus, we conclude that CHIP inhibits the signaling activities of Smad1/5 by recruiting Smad1/5 from the functional R-/Co-Smad complex and further promoting the ubiquitination/degradation of Smad1/5 in a chaperone-independent manner.


Asunto(s)
Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Secuencias de Aminoácidos , Células HEK293 , Proteínas del Choque Térmico HSC70/química , Proteínas del Choque Térmico HSC70/genética , Proteínas del Choque Térmico HSC70/metabolismo , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Péptidos/química , Péptidos/genética , Péptidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Transducción de Señal/fisiología , Proteína Smad1/química , Proteína Smad1/genética , Proteína Smad5/química , Proteína Smad5/genética , Factor de Crecimiento Transformador beta/química , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación/fisiología
16.
J Hazard Mater ; 435: 129077, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35650732

RESUMEN

Cadmium (Cd) pollution in croplands is a global environmental problem. Measures to improve the tolerance of sensitive crops and reduce pollutant absorption and accumulation are needed in contaminated agricultural areas, and inoculation with rhizosphere microorganisms to regulate plant resistance and heavy metal transport can provide an effective solution. A pot experiment was conducted to analyse the impact of arbuscular mycorrhizal fungi (AMF) on alfalfa oxidase activity, heavy metal resistance genes and transport proteins, metabolism, and other biochemical regulation mechanisms that lead to complexation, compartmentalisation, efflux, enrichment, and antioxidant detoxification pathways. The AMF reduced shoot and protoplasm Cd inflow, and promoted organic compound production (e.g., by upregulating HM-Res4 for 1.2 times), to complex with Cd, reducing its biological toxicity. The AMF increased the ROS scavenging efficiency and osmotic regulatory substance content of the alfalfa plants, reduced oxidative stress (ROS dereased), and maintained homeostasis. It also alleviated Cd inhibition of photosynthetic electron transport, tricarboxylic acid circulation, and nitrogen assimilation. These AMF effects improved leaf and root biomass by 43.87% and 59.71% and facilitated recovery of a conservative root economic strategy. It is speculated that AMF induces the resistance signal switch by regulating the negative feedback regulation mode of indole acetic acid upward transport and methyl jasmonate downward transmission in plants.


Asunto(s)
Metales Pesados , Micorrizas , Contaminantes del Suelo , Cadmio/metabolismo , Medicago sativa/metabolismo , Metales Pesados/metabolismo , Micorrizas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Contaminantes del Suelo/metabolismo
17.
Adv Mater ; 34(33): e2202695, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35747910

RESUMEN

It is still very urgent and challenging to simultaneously develop high-rate and long-cycle oxide cathodes for sodium-ion batteries (SIBs) because of the sluggish kinetics and complex multiphase evolution during cycling. Here, the concept of accurately manipulating structural evolution and formulating high-performance heterostructured biphasic layered oxide cathodes by local chemistry and orbital hybridization modulation is reported. The P2-structure stoichiometric composition of the cathode material shows a layered P2- and O3-type heterostructure that is explicitly evidenced by various macroscale and atomic-scale techniques. Surprisingly, the heterostructured cathode displays excellent rate performance, remarkable cycling stability (capacity retention of 82.16% after 600 cycles at 2 C), and outstanding compatibility with hard carbon anode because of the integrated advantages of intergrowth structure and local environment regulation. Meanwhile, the formation process from precursors during calcination and the highly reversible dynamic structural evolution during the Na+ intercalation/deintercalation process are clearly articulated by a series of in situ characterization techniques. Also, the intrinsic structural properties and corresponding electrochemical behavior are further elucidated by the density of states and electron localization function of density functional theory calculations. Overall, this strategy, which finely tunes the local chemistry and orbitals hybridization for high-performance SIBs, will open up a new field for other materials.

18.
Nanoscale ; 14(3): 1008-1013, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34989750

RESUMEN

Aqueous zinc-ion batteries (ZIBs) are widely recognized for their excellent safety and high theoretical capacity but are hindered by the scarcity of cathode materials with high-rate performance and stability. Herein, a dual conducting network corbelled hydrated vanadium pentoxide that involves structural water as a pillar to enlarge the layer spacing of vanadium pentoxide and ensure cycling stability was reported. Along with the proton co-insertion, the hydrated vanadium pentoxide delivers nearly theoretical specific capacities of 524.6 mA h g-1 at 0.3 A g-1 and 258.7 mA h g-1 at 10 A g-1, which was largely due to non-faradaic contribution, and retains 196.8 mA h g-1 at 4.8 A g-1 after 1100 cycles. Notably, a high energy density of 409.3 W h kg-1 at 0.3 A g-1 and a power density of 6666.4 W kg-1 at 10 A g-1 have also been achieved. The design strategy offers a potential path to develop high-rate ZIBs.

19.
Nat Commun ; 13(1): 6004, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36224181

RESUMEN

Aberrant activation of EGFR due to overexpression or mutation is associated with poor prognosis in many types of tumors. Here we show that blocking the sorting system that directs EGFR to plasma membrane is a potent strategy to treat EGFR-dependent tumors. We find that EGFR palmitoylation by DHHC13 is critical for its plasma membrane localization and identify ARF6 as a key factor in this process. N-myristoylated ARF6 recognizes palmitoylated EGFR via lipid-lipid interaction, recruits the exocyst complex to promote EGFR budding from Golgi, and facilitates EGFR transporting to plasma membrane in a GTP-bound form. To evaluate the therapeutic potential of this sorting system, we design a cell-permeable peptide, N-myristoylated GKVL-TAT, and find it effectively disrupts plasma membrane localization of EGFR and significantly inhibits progression of EGFR-dependent tumors. Our findings shed lights on the underlying mechanism of how palmitoylation directs protein sorting and provide an potential strategy to manage EGFR-dependent tumors.


Asunto(s)
Factores de Ribosilacion-ADP , Neoplasias , Factores de Ribosilacion-ADP/metabolismo , Membrana Celular/metabolismo , Receptores ErbB/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Lípidos , Neoplasias/metabolismo , Transporte de Proteínas
20.
Sci Signal ; 15(721): eabi9983, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35167340

RESUMEN

To perform their antiviral and antitumor functions, T cells must integrate signals both from the T cell receptor (TCR), which instruct the cell to remain quiescent or become activated, and from cytokines that guide cellular proliferation and differentiation. In mature CD8+ T cells, Themis has been implicated in integrating TCR and cytokine signals. We investigated whether Themis plays a direct role in cytokine signaling in mature T cells. Themis was required for IL-2- and IL-15-driven CD8+ T cell proliferation both in mice and in vitro. Mechanistically, we found that Themis promoted the activation of the transcription factor Stat and mechanistic target of rapamycin signaling downstream of cytokine receptors. Metabolomics and stable isotope tracing analyses revealed that Themis deficiency reduced glycolysis and serine and nucleotide biosynthesis, demonstrating a receptor-proximal requirement for Themis in triggering the metabolic changes that enable T cell proliferation. The cellular, metabolic, and biochemical defects caused by Themis deficiency were corrected in mice lacking both Themis and the phosphatase Shp1, suggesting that Themis mediates IL-2 and IL-15 receptor-proximal signaling by restraining the activity of Shp1. Together, these results not only shed light on the mechanisms of cytokine signaling but also provide new clues on manipulating T cells for clinical applications.


Asunto(s)
Linfocitos T CD8-positivos , Interleucina-2 , Animales , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Péptidos y Proteínas de Señalización Intercelular , Interleucina-15/genética , Interleucina-2/genética , Ratones , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo
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