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1.
Cell ; 186(2): 279-286.e8, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36580913

RESUMEN

The BQ and XBB subvariants of SARS-CoV-2 Omicron are now rapidly expanding, possibly due to altered antibody evasion properties deriving from their additional spike mutations. Here, we report that neutralization of BQ.1, BQ.1.1, XBB, and XBB.1 by sera from vaccinees and infected persons was markedly impaired, including sera from individuals boosted with a WA1/BA.5 bivalent mRNA vaccine. Titers against BQ and XBB subvariants were lower by 13- to 81-fold and 66- to 155-fold, respectively, far beyond what had been observed to date. Monoclonal antibodies capable of neutralizing the original Omicron variant were largely inactive against these new subvariants, and the responsible individual spike mutations were identified. These subvariants were found to have similar ACE2-binding affinities as their predecessors. Together, our findings indicate that BQ and XBB subvariants present serious threats to current COVID-19 vaccines, render inactive all authorized antibodies, and may have gained dominance in the population because of their advantage in evading antibodies.


Asunto(s)
Anticuerpos Antivirales , COVID-19 , Evasión Inmune , SARS-CoV-2 , Humanos , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , COVID-19/inmunología , COVID-19/virología , Vacunas contra la COVID-19 , SARS-CoV-2/clasificación , SARS-CoV-2/genética
2.
Immunity ; 56(10): 2442-2455.e8, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37776849

RESUMEN

SARS-CoV-2 continues to evolve, with many variants evading clinically authorized antibodies. To isolate monoclonal antibodies (mAbs) with broadly neutralizing capacities against the virus, we screened serum samples from convalescing COVID-19 patients. We isolated two mAbs, 12-16 and 12-19, which neutralized all SARS-CoV-2 variants tested, including the XBB subvariants, and prevented infection in hamsters challenged with Omicron BA.1 intranasally. Structurally, both antibodies targeted a conserved quaternary epitope located at the interface between the N-terminal domain and subdomain 1, uncovering a site of vulnerability on SARS-CoV-2 spike. These antibodies prevented viral receptor engagement by locking the receptor-binding domain (RBD) of spike in the down conformation, revealing a mechanism of virus neutralization for non-RBD antibodies. Deep mutational scanning showed that SARS-CoV-2 could mutate to escape 12-19, but such mutations are rarely found in circulating viruses. Antibodies 12-16 and 12-19 hold promise as prophylactic agents for immunocompromised persons who do not respond robustly to COVID-19 vaccines.


Asunto(s)
COVID-19 , Glicoproteína de la Espiga del Coronavirus , Animales , Cricetinae , Humanos , Vacunas contra la COVID-19 , SARS-CoV-2 , Receptores Virales , Anticuerpos Monoclonales , Anticuerpos Antivirales , Anticuerpos Neutralizantes
3.
Cell ; 165(7): 1621-1631, 2016 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-27315479

RESUMEN

While the search for an efficacious HIV-1 vaccine remains elusive, emergence of a new generation of virus-neutralizing monoclonal antibodies (mAbs) has re-ignited the field of passive immunization for HIV-1 prevention. However, the plasticity of HIV-1 demands additional improvements to these mAbs to better ensure their clinical utility. Here, we report engineered bispecific antibodies that are the most potent and broad HIV-neutralizing antibodies to date. One bispecific antibody, 10E8V2.0/iMab, neutralized 118 HIV-1 pseudotyped viruses tested with a mean 50% inhibitory concentration (IC50) of 0.002 µg/mL. 10E8V2.0/iMab also potently neutralized 99% of viruses in a second panel of 200 HIV-1 isolates belonging to clade C, the dominant subtype accounting for ∼50% of new infections worldwide. Importantly, 10E8V2.0/iMab reduced virus load substantially in HIV-1-infected humanized mice and also provided complete protection when administered prior to virus challenge. These bispecific antibodies hold promise as novel prophylactic and/or therapeutic agents in the fight against HIV-1.


Asunto(s)
Anticuerpos Biespecíficos/inmunología , Anticuerpos Neutralizantes/inmunología , Proteínas gp160 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Animales , Anticuerpos Biespecíficos/química , Anticuerpos Monoclonales/química , Anticuerpos Neutralizantes/química , Proteínas gp160 de Envoltorio del VIH/química , Infecciones por VIH/prevención & control , Infecciones por VIH/terapia , Humanos , Inmunización Pasiva , Ratones
4.
Nature ; 624(7992): 639-644, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37871613

RESUMEN

A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariant, BA.2.86, has emerged and spread to numerous countries worldwide, raising alarm because its spike protein contains 34 additional mutations compared with its BA.2 predecessor1. We examined its antigenicity using human sera and monoclonal antibodies (mAbs). Reassuringly, BA.2.86 was no more resistant to human sera than the currently dominant XBB.1.5 and EG.5.1, indicating that the new subvariant would not have a growth advantage in this regard. Importantly, sera from people who had XBB breakthrough infection exhibited robust neutralizing activity against all viruses tested, suggesting that upcoming XBB.1.5 monovalent vaccines could confer added protection. Although BA.2.86 showed greater resistance to mAbs to subdomain 1 (SD1) and receptor-binding domain (RBD) class 2 and 3 epitopes, it was more sensitive to mAbs to class 1 and 4/1 epitopes in the 'inner face' of the RBD that is exposed only when this domain is in the 'up' position. We also identified six new spike mutations that mediate antibody resistance, including E554K that threatens SD1 mAbs in clinical development. The BA.2.86 spike also had a remarkably high receptor affinity. The ultimate trajectory of this new SARS-CoV-2 variant will soon be revealed by continuing surveillance, but its worldwide spread is worrisome.


Asunto(s)
Epítopos de Linfocito B , Receptores Virales , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Epítopos de Linfocito B/inmunología , Inmunogenicidad Vacunal , Mutación , Receptores Virales/metabolismo , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Sueros Inmunes/inmunología
5.
Nature ; 617(7962): 717-723, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37225883

RESUMEN

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

6.
Nature ; 608(7923): 603-608, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35790190

RESUMEN

SARS-CoV-2 Omicron subvariants BA.2.12.1 and BA.4/5 have surged notably to become dominant in the United States and South Africa, respectively1,2. These new subvariants carrying further mutations in their spike proteins raise concerns that they may further evade neutralizing antibodies, thereby further compromising the efficacy of COVID-19 vaccines and therapeutic monoclonals. We now report findings from a systematic antigenic analysis of these surging Omicron subvariants. BA.2.12.1 is only modestly (1.8-fold) more resistant to sera from vaccinated and boosted individuals than BA.2. However, BA.4/5 is substantially (4.2-fold) more resistant and thus more likely to lead to vaccine breakthrough infections. Mutation at spike residue L452 found in both BA.2.12.1 and BA.4/5 facilitates escape from some antibodies directed to the so-called class 2 and 3 regions of the receptor-binding domain3. The F486V mutation found in BA.4/5 facilitates escape from certain class 1 and 2 antibodies but compromises the spike affinity for the viral receptor. The R493Q reversion mutation, however, restores receptor affinity and consequently the fitness of BA.4/5. Among therapeutic antibodies authorized for clinical use, only bebtelovimab retains full potency against both BA.2.12.1 and BA.4/5. The Omicron lineage of SARS-CoV-2 continues to evolve, successively yielding subvariants that are not only more transmissible but also more evasive to antibodies.


Asunto(s)
Anticuerpos Antivirales , Deriva y Cambio Antigénico , COVID-19 , Mutación , SARS-CoV-2 , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , Deriva y Cambio Antigénico/genética , Deriva y Cambio Antigénico/inmunología , COVID-19/inmunología , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Humanos , Inmunización Secundaria , Receptores Virales/metabolismo , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo
7.
Nature ; 604(7906): 553-556, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35240676

RESUMEN

The identification of the Omicron (B.1.1.529.1 or BA.1) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Botswana in November 20211 immediately caused concern owing to the number of alterations in the spike glycoprotein that could lead to antibody evasion. We2 and others3-6 recently reported results confirming such a concern. Continuing surveillance of the evolution of Omicron has since revealed the rise in prevalence of two sublineages, BA.1 with an R346K alteration (BA.1+R346K, also known as BA.1.1) and B.1.1.529.2 (BA.2), with the latter containing 8 unique spike alterations and lacking 13 spike alterations found in BA.1. Here we extended our studies to include antigenic characterization of these new sublineages. Polyclonal sera from patients infected by wild-type SARS-CoV-2 or recipients of current mRNA vaccines showed a substantial loss in neutralizing activity against both BA.1+R346K and BA.2, with drops comparable to that already reported for BA.1 (refs. 2,3,5,6). These findings indicate that these three sublineages of Omicron are antigenically equidistant from the wild-type SARS-CoV-2 and thus similarly threaten the efficacies of current vaccines. BA.2 also exhibited marked resistance to 17 of 19 neutralizing monoclonal antibodies tested, including S309 (sotrovimab)7, which had retained appreciable activity against BA.1 and BA.1+R346K (refs. 2-4,6). This finding shows that no authorized monoclonal antibody therapy could adequately cover all sublineages of the Omicron variant, except for the recently authorized LY-CoV1404 (bebtelovimab).


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
8.
Nature ; 602(7898): 676-681, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35016198

RESUMEN

The B.1.1.529/Omicron variant of SARS-CoV-2 was only recently detected in southern Africa, but its subsequent spread has been extensive, both regionally and globally1. It is expected to become dominant in the coming weeks2, probably due to enhanced transmissibility. A striking feature of this variant is the large number of spike mutations3 that pose a threat to the efficacy of current COVID-19 vaccines and antibody therapies4. This concern is amplified by the findings of our study. Here we found that B.1.1.529 is markedly resistant to neutralization by serum not only from patients who recovered from COVID-19, but also from individuals who were vaccinated with one of the four widely used COVID-19 vaccines. Even serum from individuals who were vaccinated and received a booster dose of mRNA-based vaccines exhibited substantially diminished neutralizing activity against B.1.1.529. By evaluating a panel of monoclonal antibodies against all known epitope clusters on the spike protein, we noted that the activity of 17 out of the 19 antibodies tested were either abolished or impaired, including ones that are currently authorized or approved for use in patients. Moreover, we also identified four new spike mutations (S371L, N440K, G446S and Q493R) that confer greater antibody resistance on B.1.1.529. The Omicron variant presents a serious threat to many existing COVID-19 vaccines and therapies, compelling the development of new interventions that anticipate the evolutionary trajectory of SARS-CoV-2.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/virología , Evasión Inmune/inmunología , SARS-CoV-2/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/sangre , COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Línea Celular , Convalecencia , Evolución Molecular , Humanos , Sueros Inmunes/inmunología , Concentración 50 Inhibidora , Modelos Moleculares , Mutación , Pruebas de Neutralización , SARS-CoV-2/química , SARS-CoV-2/clasificación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología
9.
PLoS Biol ; 22(5): e3002621, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38805565

RESUMEN

Cholesterol metabolism is vital for multiple cancer progression, while how cholesterol affects lung, a low-cholesterol tissue, for cancer metastasis and the underlying mechanism remain unclear. In this study, we found that metastatic lung adenocarcinoma cells acquire cellular dehydrocholesterol and cholesterol by endogenous cholesterol biosynthesis, instead of uptake upon cholesterol treatment. Besides, we demonstrated that exogenous cholesterol functions as signaling molecule to induce FOXA3, a key transcription factor for lipid metabolism via GLI2. Subsequently, ChIP-seq analysis and molecular studies revealed that FOXA3 transcriptionally activated Hmgcs1, an essential enzyme of cholesterol biosynthesis, to induce endogenous dehydrocholesterol and cholesterol level for membrane composition change and cell migration. Conversely, FOXA3 knockdown or knockout blocked cholesterol biosynthesis and lung adenocarcinoma metastasis in mice. In addition, the potent FOXA3 inhibitor magnolol suppressed metastatic gene programs in lung adenocarcinoma patient-derived organoids (PDOs). Altogether, our findings shed light onto unique cholesterol metabolism and FOXA3 contribution to lung adenocarcinoma metastasis.


Asunto(s)
Adenocarcinoma del Pulmón , Colesterol , Progresión de la Enfermedad , Factor Nuclear 3-gamma del Hepatocito , Neoplasias Pulmonares , Colesterol/metabolismo , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/genética , Animales , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Ratones , Factor Nuclear 3-gamma del Hepatocito/metabolismo , Factor Nuclear 3-gamma del Hepatocito/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Movimiento Celular
10.
Nature ; 593(7857): 130-135, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33684923

RESUMEN

The COVID-19 pandemic has had widespread effects across the globe, and its causative agent, SARS-CoV-2, continues to spread. Effective interventions need to be developed to end this pandemic. Single and combination therapies with monoclonal antibodies have received emergency use authorization1-3, and more treatments are under development4-7. Furthermore, multiple vaccine constructs have shown promise8, including two that have an approximately 95% protective efficacy against COVID-199,10. However, these interventions were directed against the initial SARS-CoV-2 virus that emerged in 2019. The recent detection of SARS-CoV-2 variants B.1.1.7 in the UK11 and B.1.351 in South Africa12 is of concern because of their purported ease of transmission and extensive mutations in the spike protein. Here we show that B.1.1.7 is refractory to neutralization by most monoclonal antibodies against the N-terminal domain of the spike protein and is relatively resistant to a few monoclonal antibodies against the receptor-binding domain. It is not more resistant to plasma from individuals who have recovered from COVID-19 or sera from individuals who have been vaccinated against SARS-CoV-2. The B.1.351 variant is not only refractory to neutralization by most monoclonal antibodies against the N-terminal domain but also by multiple individual monoclonal antibodies against the receptor-binding motif of the receptor-binding domain, which is mostly due to a mutation causing an E484K substitution. Moreover, compared to wild-type SARS-CoV-2, B.1.351 is markedly more resistant to neutralization by convalescent plasma (9.4-fold) and sera from individuals who have been vaccinated (10.3-12.4-fold). B.1.351 and emergent variants13,14 with similar mutations in the spike protein present new challenges for monoclonal antibody therapies and threaten the protective efficacy of current vaccines.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/terapia , Evasión Inmune/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto , Anciano , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , COVID-19/prevención & control , COVID-19/virología , Chlorocebus aethiops , Farmacorresistencia Viral/inmunología , Células HEK293 , Humanos , Evasión Inmune/genética , Inmunización Pasiva , Persona de Mediana Edad , Modelos Moleculares , Mutación , Pruebas de Neutralización , Dominios Proteicos/inmunología , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Vacunas Sintéticas/inmunología , Células Vero , Sueroterapia para COVID-19 , Tratamiento Farmacológico de COVID-19 , Vacunas de ARNm
11.
Proc Natl Acad Sci U S A ; 121(14): e2317574121, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38530899

RESUMEN

Fine particulate matter (PM2.5) is globally recognized for its adverse implications on human health. Yet, remain limited the individual contribution of particular PM2.5 components to its toxicity, especially considering regional disparities. Moreover, prevention solutions for PM2.5-associated health effects are scarce. In the present study, we comprehensively characterized and compared the primary PM2.5 constituents and their altered metabolites from two locations: Taiyuan and Guangzhou. Analysis of year-long PM2.5 samples revealed 84 major components, encompassing organic carbon, elemental carbon, ions, metals, and organic chemicals. PM2.5 from Taiyuan exhibited higher contamination, associated health risks, dithiothreitol activity, and cytotoxicities than Guangzhou's counterpart. Applying metabolomics, BEAS-2B lung cells exposed to PM2.5 from both cities were screened for significant alterations. A correlation analysis revealed the metabolites altered by PM2.5 and the critical toxic PM2.5 components in both regions. Among the PM2.5-down-regulated metabolites, phosphocholine emerged as a promising intervention for PM2.5 cytotoxicities. Its supplementation effectively attenuated PM2.5-induced energy metabolism disorder and cell death via activating fatty acid oxidation and inhibiting Phospho1 expression. The highlighted toxic chemicals displayed combined toxicities, potentially counteracted by phosphocholine. Our study offered a promising functional metabolite to alleviate PM2.5-induced cellular disorder and provided insights into the geo-based variability in toxic PM2.5 components.


Asunto(s)
Contaminantes Atmosféricos , Enfermedades Mitocondriales , Humanos , Contaminantes Atmosféricos/análisis , Fosforilcolina , Material Particulado/análisis , Pulmón , Carbono/análisis , Monitoreo del Ambiente
12.
Nature ; 584(7821): 450-456, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32698192

RESUMEN

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic continues, with devasting consequences for human lives and the global economy1,2. The discovery and development of virus-neutralizing monoclonal antibodies could be one approach to treat or prevent infection by this coronavirus. Here we report the isolation of sixty-one SARS-CoV-2-neutralizing monoclonal antibodies from five patients infected with SARS-CoV-2 and admitted to hospital with severe coronavirus disease 2019 (COVID-19). Among these are nineteen antibodies that potently neutralized authentic SARS-CoV-2 in vitro, nine of which exhibited very high potency, with 50% virus-inhibitory concentrations of 0.7 to 9 ng ml-1. Epitope mapping showed that this collection of nineteen antibodies was about equally divided between those directed against the receptor-binding domain (RBD) and those directed against the N-terminal domain (NTD), indicating that both of these regions at the top of the viral spike are immunogenic. In addition, two other powerful neutralizing antibodies recognized quaternary epitopes that overlap with the domains at the top of the spike. Cryo-electron microscopy reconstructions of one antibody that targets the RBD, a second that targets the NTD, and a third that bridges two separate RBDs showed that the antibodies recognize the closed, 'all RBD-down' conformation of the spike. Several of these monoclonal antibodies are promising candidates for clinical development as potential therapeutic and/or prophylactic agents against SARS-CoV-2.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Epítopos de Linfocito B/inmunología , Neumonía Viral/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Animales , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/ultraestructura , Anticuerpos Neutralizantes/análisis , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/ultraestructura , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/química , Anticuerpos Antivirales/ultraestructura , Betacoronavirus/química , Betacoronavirus/ultraestructura , COVID-19 , Infecciones por Coronavirus/prevención & control , Microscopía por Crioelectrón , Modelos Animales de Enfermedad , Mapeo Epitopo , Epítopos de Linfocito B/química , Epítopos de Linfocito B/ultraestructura , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/ultraestructura , Pulmón/patología , Pulmón/virología , Masculino , Mesocricetus , Modelos Moleculares , Pruebas de Neutralización , Pandemias/prevención & control , Neumonía Viral/prevención & control , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/ultraestructura
13.
Plant J ; 119(1): 283-299, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38606500

RESUMEN

Drought stress is one of the dominating challenges to the growth and productivity in crop plants. Elucidating the molecular mechanisms of plants responses to drought stress is fundamental to improve fruit quality. However, such molecular mechanisms are poorly understood in apple (Malus domestica Borkh.). In this study, we explored that the BTB-BACK-TAZ protein, MdBT2, negatively modulates the drought tolerance of apple plantlets. Moreover, we identified a novel Homeodomain-leucine zipper (HD-Zip) transcription factor, MdHDZ27, using a yeast two-hybrid (Y2H) screen with MdBT2 as the bait. Overexpression of MdHDZ27 in apple plantlets, calli, and tomato plantlets enhanced their drought tolerance by promoting the expression of drought tolerance-related genes [responsive to dehydration 29A (MdRD29A) and MdRD29B]. Biochemical analyses demonstrated that MdHDZ27 directly binds to and activates the promoters of MdRD29A and MdRD29B. Furthermore, in vitro and in vivo assays indicate that MdBT2 interacts with and ubiquitinates MdHDZ27, via the ubiquitin/26S proteasome pathway. This ubiquitination results in the degradation of MdHDZ27 and weakens the transcriptional activation of MdHDZ27 on MdRD29A and MdRD29B. Finally, a series of transgenic analyses in apple plantlets further clarified the role of the relationship between MdBT2 and MdHDZ27, as well as the effect of their interaction on drought resistance in apple plantlets. Collectively, our findings reveal a novel mechanism by which the MdBT2-MdHDZ27 regulatory module controls drought tolerance, which is of great significance for enhancing the drought resistance of apple and other plants.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Malus , Proteínas de Plantas , Plantas Modificadas Genéticamente , Factores de Transcripción , Ubiquitinación , Malus/genética , Malus/fisiología , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estrés Fisiológico , Resistencia a la Sequía
14.
PLoS Comput Biol ; 20(4): e1012012, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38574114

RESUMEN

Anti-cancer response of cell lines to drugs is in urgent need for individualized precision medical decision-making in the era of precision medicine. Measurements with wet-experiments is time-consuming and expensive and it is almost impossible for wide ranges of application. The design of computational models that can precisely predict the responses between drugs and cell lines could provide a credible reference for further research. Existing methods of response prediction based on matrix factorization or neural networks have revealed that both linear or nonlinear latent characteristics are applicable and effective for the precise prediction of drug responses. However, the majority of them consider only linear or nonlinear relationships for drug response prediction. Herein, we propose a Dual Branch Deep Neural Matrix Factorization (DBDNMF) method to address the above-mentioned issues. DBDNMF learns the latent representation of drugs and cell lines through flexible inputs and reconstructs the partially observed matrix through a series of hidden neural network layers. Experimental results on the datasets of Cancer Cell Line Encyclopedia (CCLE) and Genomics of Drug Sensitivity in Cancer (GDSC) show that the accuracy of drug prediction exceeds state-of-the-art drug response prediction algorithms, demonstrating its reliability and stability. The hierarchical clustering results show that drugs with similar response levels tend to target similar signaling pathway, and cell lines coming from the same tissue subtype tend to share the same pattern of response, which are consistent with previously published studies.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Reproducibilidad de los Resultados , Medicina de Precisión/métodos , Línea Celular Tumoral
15.
Proc Natl Acad Sci U S A ; 119(51): e2211775119, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36508676

RESUMEN

Synthetic lethality is a powerful approach for targeting oncogenic drivers in cancer. Recent studies revealed that cancer cells with microsatellite instability (MSI) require Werner (WRN) helicase for survival; however, the underlying mechanism remains unclear. In this study, we found that WRN depletion strongly induced p53 and its downstream apoptotic target PUMA in MSI colorectal cancer (CRC) cells. p53 or PUMA deletion abolished apoptosis induced by WRN depletion in MSI CRC cells. Importantly, correction of MSI abrogated the activation of p53/PUMA and cell killing, while induction of MSI led to sensitivity in isogenic CRC cells. Rare p53-mutant MSI CRC cells are resistant to WRN depletion due to lack of PUMA induction, which could be restored by wildtype (WT) p53 knock in or reconstitution. WRN depletion or treatment with the RecQ helicase inhibitor ML216 suppressed in vitro and in vivo growth of MSI CRCs in a p53/PUMA-dependent manner. ML216 treatment was efficacious in MSI CRC patient-derived xenografts. Interestingly, p53 gene remains WT in the majority of MSI CRCs. These results indicate a critical role of p53/PUMA-mediated apoptosis in the vulnerability of MSI CRCs to WRN loss, and support WRN as a promising therapeutic target in p53-WT MSI CRCs.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Humanos , Helicasa del Síndrome de Werner/genética , Proteína p53 Supresora de Tumor/genética , Inestabilidad de Microsatélites , Neoplasias Colorrectales/genética , RecQ Helicasas/genética
16.
J Biol Chem ; 299(11): 105294, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37774972

RESUMEN

The glycoside hydrolase family 55 (GH55) includes inverting exo-ß-1,3-glucosidases and endo-ß-1,3-glucanases, acting on laminarin, which is a ß1-3/1-6-glucan consisting of a ß1-3/1-6-linked main chain and ß1-6-linked branches. Despite their different modes of action toward laminarin, endo-ß-1,3-glucanases share with exo-ß-1,3-glucosidases conserved residues that form the dead-end structure of subsite -1. Here, we investigated the mechanism of endo-type action on laminarin by GH55 endo-ß-1,3-glucanase MnLam55A, identified from Microdochium nivale. MnLam55A, like other endo-ß-1,3-glucanases, degraded internal ß-d-glucosidic linkages of laminarin, producing more reducing sugars than the sum of d-glucose and gentiooligosaccharides detected. ß1-3-Glucans lacking ß1-6-linkages in the main chain were not hydrolyzed. NMR analysis of the initial degradation of laminarin revealed that MnLam55A preferentially cleaved the nonreducing terminal ß1-3-linkage of the laminarioligosaccharide moiety at the reducing end side of the main chain ß1-6-linkage. MnLam55A liberates d-glucose from laminaritriose and longer laminarioligosaccharides, but kcat/Km values to laminarioligosaccharides (≤4.21 s-1 mM-1) were much lower than to laminarin (5920 s-1 mM-1). These results indicate that ß-glucan binding to the minus subsites of MnLam55A, including exclusive binding of the gentiobiosyl moiety to subsites -1 and -2, is required for high hydrolytic activity. A crystal structure of MnLam55A, determined at 2.4 Å resolution, showed that MnLam55A adopts an overall structure and catalytic site similar to those of exo-ß-1,3-glucosidases. However, MnLam55A possesses an extended substrate-binding cleft that is expected to form the minus subsites. Sequence comparison suggested that other endo-type enzymes share the extended cleft. The specific hydrolysis of internal linkages in laminarin is presumably common to GH55 endo-ß-1,3-glucanases.


Asunto(s)
Glicósido Hidrolasas , beta-Glucanos , Glucanos/metabolismo , Glucosa , Glucosidasas/metabolismo , Glicósido Hidrolasas/metabolismo , Especificidad por Sustrato
17.
J Biol Chem ; 299(4): 103059, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36841479

RESUMEN

Peroxisome proliferator-activated receptor γ (PPARγ) is a master regulator of adipocyte differentiation, glucolipid metabolism, and inflammation. Thiazolidinediones are PPARγ full agonists with potent insulin-sensitizing effects, whereas their oral usage is restricted because of unwanted side effects, including obesity and cardiovascular risks. Here, via virtual screening, microscale thermophoresis analysis, and molecular confirmation, we demonstrate that diosmin, a natural compound of wide and long-term clinical use, is a selective PPARγ modulator that binds to PPARγ and blocks PPARγ phosphorylation with weak transcriptional activity. Local diosmin administration in subcutaneous fat (inguinal white adipose tissue [iWAT]) improved insulin sensitivity and attenuated obesity via enhancing browning of white fat and energy expenditure. Besides, diosmin ameliorated inflammation in WAT and liver and reduced hepatic steatosis. Of note, we determined that iWAT local administration of diosmin did not exhibit obvious side effects. Taken together, the present study demonstrated that iWAT local delivery of diosmin protected mice from diet-induced insulin resistance, obesity, and fatty liver by blocking PPARγ phosphorylation, without apparent side effects, making it a potential therapeutic agent for the treatment of metabolic diseases.


Asunto(s)
Tejido Adiposo Pardo , Tejido Adiposo Blanco , Diosmina , Hígado Graso , Resistencia a la Insulina , PPAR gamma , Animales , Ratones , Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Dieta Alta en Grasa , Diosmina/farmacología , Diosmina/metabolismo , Diosmina/uso terapéutico , Hígado Graso/metabolismo , Inflamación/metabolismo , Ratones Endogámicos C57BL , Obesidad/metabolismo , PPAR gamma/metabolismo , Tejido Adiposo Pardo/metabolismo
18.
Plant J ; 115(2): 398-413, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37021636

RESUMEN

The potato's most devastating disease is late blight, which is caused by Phytophthora infestans. Whereas various resistance (R) genes are known, most are typically defeated by this fast-evolving oomycete pathogen. However, the broad-spectrum and durable R8 is a vital gene resource for potato resistance breeding. To support an educated deployment of R8, we embarked on a study on the corresponding avirulence gene Avr8. We overexpressed Avr8 by transient and stable transformation, and found that Avr8 promotes colonization of P. infestans in Nicotiana benthamiana and potato, respectively. A yeast-two-hybrid (Y2H) screen showed that AVR8 interacts with a desumoylating isopeptidase (StDeSI2) of potato. We overexpressed DeSI2 and found that DeSI2 positively regulates resistance to P. infestans, while silencing StDeSI2 downregulated the expression of a set of defense-related genes. By using a specific proteasome inhibitor, we found that AVR8 destabilized StDeSI2 through the 26S proteasome and attenuated early PTI responses. Altogether, these results indicate that AVR8 manipulates desumoylation, which is a new strategy that adds to the plethora of mechanisms that Phytophthora exploits to modulate host immunity, and StDeSI2 provides a new target for durable resistance breeding against P. infestans in potato.


Asunto(s)
Phytophthora infestans , Solanum tuberosum , Fitomejoramiento , Inmunidad de la Planta , Solanum tuberosum/genética , Enfermedades de las Plantas
19.
Mol Biol Evol ; 40(5)2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37140205

RESUMEN

Gene loss is a prevalent source of genetic variation in genome evolution. Calling loss events effectively and efficiently is a critical step for systematically characterizing their functional and phylogenetic profiles genome wide. Here, we developed a novel pipeline integrating orthologous inference and genome alignment. Interestingly, we identified 33 gene loss events that give rise to evolutionarily novel long noncoding RNAs (lncRNAs) that show distinct expression features and could be associated with various functions related to growth, development, immunity, and reproduction, suggesting loss relics as a potential source of functional lncRNAs in humans. Our data also demonstrated that the rates of protein gene loss are variable among different lineages with distinct functional biases.


Asunto(s)
ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Perfilación de la Expresión Génica , Filogenia , Genoma
20.
Cancer ; 130(12): 2139-2149, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38315517

RESUMEN

BACKGROUND: Although the prognosis of Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) has improved with the introduction of tyrosine kinase inhibitors (TKIs) and stem cell transplantation, prevention of relapse after transplantation remains a concern. The aim of this study was to compare the impact of TKI prophylaxis with imatinib and dasatinib on long-term outcomes after transplantation. METHODS: Patients with Ph+ ALL who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) at first complete remission (CR1) and received TKI prophylaxis after allo-HSCT were included in this retrospective analysis. Two cohorts were established based on the choice of TKI prophylaxis: the imatinib (Ima) and dasatinib (Das) cohorts. The survival and safety outcomes of these cohorts were compared. RESULTS: Ninety-one patients in the Ima cohort and 50 in the Das cohort were included. After a median follow-up of 50.6 months, the 5-year cumulative incidence of relapse, nonrelapse mortality rate, and overall survival in the Ima and Das cohorts were 16.1% and 12.5%, 5.2% and 9.8%, and 86.5% and 77.6%, respectively, with no statistical differences. The cumulative incidence of mild chronic graft-versus-host disease was higher in the Das cohort. The most common adverse event was neutropenia (64.7% vs. 69.5%). The Das cohort had a higher incidence of gastrointestinal bleeding (25.5% vs. 2.3%) and gastrointestinal reaction (48.9% vs. 31.4%) than the Ima cohort. The proportion of patients treated on schedule was significantly lower in the Das cohort than in the Ima cohort, and drug intolerance was the main reason for protocol violation. CONCLUSIONS: For patients with Ph+ ALL undergoing allo-HSCT in CR1, imatinib prophylaxis achieved long-term outcomes similar to those of dasatinib.


Asunto(s)
Dasatinib , Trasplante de Células Madre Hematopoyéticas , Mesilato de Imatinib , Leucemia-Linfoma Linfoblástico de Células Precursoras , Inhibidores de Proteínas Quinasas , Trasplante Homólogo , Humanos , Dasatinib/uso terapéutico , Dasatinib/efectos adversos , Estudios Retrospectivos , Masculino , Femenino , Adulto , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Persona de Mediana Edad , Mesilato de Imatinib/uso terapéutico , Adulto Joven , Adolescente , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Resultado del Tratamiento , Antineoplásicos/uso terapéutico , Antineoplásicos/efectos adversos , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/etiología
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