RESUMEN
Almost all the neutralizing antibodies targeting the receptor-binding domain (RBD) of spike (S) protein show weakened or lost efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged or emerging variants, such as Omicron and its sub-variants. This suggests that highly conserved epitopes are crucial for the development of neutralizing antibodies. Here, we present one nanobody, N235, displaying broad neutralization against the SARS-CoV-2 prototype and multiple variants, including the newly emerged Omicron and its sub-variants. Cryo-electron microscopy demonstrates N235 binds a novel, conserved, cryptic epitope in the N-terminal domain (NTD) of the S protein, which interferes with the RBD in the neighboring S protein. The neutralization mechanism interpreted via flow cytometry and Western blot shows that N235 appears to induce the S1 subunit shedding from the trimeric S complex. Furthermore, a nano-IgM construct (MN235), engineered by fusing N235 with the human IgM Fc region, displays prevention via inducing S1 shedding and cross-linking virus particles. Compared to N235, MN235 exhibits varied enhancement in neutralization against pseudotyped and authentic viruses in vitro. The intranasal administration of MN235 in low doses can effectively prevent the infection of Omicron sub-variant BA.1 and XBB in vivo, suggesting that it can be developed as a promising prophylactic antibody to cope with the ongoing and future infection.
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Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Epítopos , Inmunoglobulina M , SARS-CoV-2 , Anticuerpos de Dominio Único , Glicoproteína de la Espiga del Coronavirus , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/química , Humanos , Anticuerpos de Dominio Único/inmunología , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/farmacología , Epítopos/inmunología , Epítopos/genética , Epítopos/química , Animales , COVID-19/inmunología , COVID-19/virología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/química , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/genética , Inmunoglobulina M/inmunología , Inmunoglobulina M/genética , Ratones , Dominios Proteicos , Microscopía por CrioelectrónRESUMEN
BACKGROUND: Nutrition service needs are huge in China. Previous studies indicated that personalized nutrition (PN) interventions were effective. The aim of the present study is to identify the effectiveness and feasibility of a novel PN approach supported by artificial intelligence (AI). METHODS: This study is a two-arm parallel, randomized, controlled trial in real world scenario. The participants will be enrolled among who consume lunch at a staff canteen. In Phase I, a total of 170 eligible participants will be assigned to either intervention or control group on 1:1 ratio. The intervention group will be instructed to use the smartphone applet to record their lunches and reach the real-time AI-based information of dish nutrition evaluation and PN evaluation after meal consumption for 3 months. The control group will receive no nutrition information but be asked to record their lunches though the applet. Dietary pattern, body weight or blood pressure optimizing is expected after the intervention. In phase II, the applet will be free to all the diners (about 800) at the study canteen for another one year. Who use the applet at least 2 days per week will be regarded as the intervention group while the others will be the control group. Body metabolism normalization is expected after this period. Generalized linear mixed models will be used to identify the dietary, anthropometric and metabolic changes. DISCUSSION: This novel approach will provide real-time AI-based dish nutrition evaluation and PN evaluation after meal consumption in order to assist users with nutrition information to make wise food choice. This study is designed under a real-life scenario which facilitates translating the trial intervention into real-world practice. TRIAL REGISTRATION: This trial has been registered with the Chinese Clinical Trial Registry (ChiCTR2100051771; date registered: 03/10/2021).
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Inteligencia Artificial , Estado Nutricional , Humanos , Programas Informáticos , Evaluación Nutricional , Peso Corporal , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Emerging Omicron sub-variants are causing global concerns, and their immune evasion should be monitored continuously. We previously evaluated the escape of Omicron BA.1, BA.1.1, BA.2, and BA.3 from an atlas of 50 monoclonal antibodies (mAbs), covering seven epitope classes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD). Here, we update the atlas of totally 77 mAbs against emerging sub-variants including BQ.1.1 and XBB and find that BA.4/5, BQ.1.1, and XBB display further evasion. Besides, investigation into the correlation of binding and neutralization of mAbs reveals the important role of antigenic conformation in mAb functioning. Moreover, the complex structures of BA.2 RBD/BD-604/S304 and BA.4/5 RBD/BD-604/S304/S309 further elucidate the molecular mechanism of antibody evasion by these sub-variants. By focusing on the identified broadly potent mAbs, we find a general hotspot epitope on the RBD, which could guide the design of vaccines and calls for new broad-spectrum countermeasures against COVID-19.
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COVID-19 , SARS-CoV-2 , Humanos , Anticuerpos Monoclonales , Epítopos , Evasión InmuneRESUMEN
Indoor air pollution is complex and serious. In fact, an on-site investigation of an office building revealed that the concentration of three typical pollutants (CO2, VOCs, PM2.5) exceeded the Chinese standard. To identify a better control method to achieve good indoor air quality, an orthogonal experiment was carried out in an environmental chamber to compare the control time and energy consumption of four control methods (purifier+ and window+, purifier+ and window-, purified fresh air 240 m3/h and purified fresh air 400 m3/h) to meet the standard established for pollutants. The purifier+ and window+ method was found to be more effective in most conditions, with a control time reduced by 8.06% and energy consumption reduced by 11.91% compared with the traditional control method of purified fresh air 240 m3/h. This research highlights the optimal control strategy for the air quality in office buildings under different pollution conditions.
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Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminantes Ambientales , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/prevención & control , Dióxido de Carbono , Monitoreo del Ambiente/métodos , Material Particulado/análisisRESUMEN
The cytoplasmic Toll/interleukin-1 receptor (TIR) domains of IL-1 receptors (IL-1Rs) are evolutionally conserved and essential for transmitting signals. IL-1RAcP is a shared co-receptor in the IL-1R family for signaling. Its splicing form IL-1RAcPb contains a different TIR domain and is unable to transduce NF-κB signaling. Here, we determined crystal structures of TIR domains of IL-1RAcPb and other IL-1Rs including IL-18Rß, IL-1RAPL2, and zebrafish SIGIRR (zSIGIRR). Structurally variant regions in the TIR domain important for signaling were revealed by structural comparisons. Taking advantage of the IL-1RAcP/IL-1RAcPb pair, we demonstrated that differential TIR domain determines signaling discrepancies between IL-1RAcP and IL-1RAcPb. We also proved the functional importance of two helices (αC and αD) in the structurally variable regions and pinpointed critical residues in αC and αD for signaling. These results collectively provide additional and important knowledge for fully understanding the molecular basis of IL-1R TIR domain in mediating signaling.
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In dynamic interferometry, the retardation error of quarter-wave plate (QWP) causes inconsistency of the background intensity and the modulation of the four phase shift interferograms, which makes the periodic ripple error in the measurement results. In this paper, an iterative algorithm is proposed to solve this problem. Both simulations and experiments validated that the algorithm can effectively eliminate the ripple error in the measurement results with stable and quick convergence, therefore the measurement accuracy of the dynamic interferometer can be improved without any extra manual operation.
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This study deals with the facility location problem of locating a set V p of p facilities on a graph such that the subgraph induced by V p is connected. We consider the connected p-median problem on a cactus graph G whose vertices and edges have nonnegative weights. The aim of a connected p-median problem is to minimize the sum of weighted distances from every vertex of a graph to the nearest vertex in V p . We provide an O(n 2 p 2) time algorithm for the connected p-median problem, where n is the number of vertices.
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Cactaceae , AlgoritmosRESUMEN
Growing evidence suggests that redox-sensitive proteins including glutaredoxins (Grxs) can protect cardiac muscle cells from oxidative stress-induced damage. Mammalian Grx3 has been shown to be critical in regulating cellular redox states. However, how Grx3 affects cardiac function by modulating reactive oxygen species (ROS) signaling remains unknown. In this study, we found that the expression of Grx3 in the heart is decreased during aging. To assess the physiological role of Grx3 in the heart, we generated mice in which Grx3 was conditionally deleted in cardiomyocytes (Grx3 conditional knockout (CKO) mice). Grx3 CKO mice were viable and grew indistinguishably from their littermates at young age. No difference in cardiac function was found comparing Grx3 CKO mice and littermate controls at this age. However, by the age of 12 months, Grx3 CKO mice exhibited left ventricular hypertrophy with a significant decrease in ejection fraction and fractional shortening along with a significant increase of ROS production in cardiomyocytes compared to controls. Deletion of Grx3 also impaired Ca2+ handling, caused enhanced sarcoplasmic reticulum (SR) calcium (Ca2+ ) leak, and decreased SR Ca2+ uptake. Furthermore, enhanced ROS production and alteration of Ca2+ handling in cardiomyocytes occurred, prior to cardiac dysfunction in young mice. Therefore, our findings demonstrate that Grx3 is an important factor in regulating cardiac hypertrophy and heart failure by modulating both cellular redox homeostasis and Ca2+ handling in the heart.
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Envejecimiento/metabolismo , Cardiomegalia/genética , Glutarredoxinas/genética , Insuficiencia Cardíaca/genética , Envejecimiento/patología , Animales , Señalización del Calcio , Cardiomegalia/metabolismo , Células Cultivadas , Glutarredoxinas/metabolismo , Insuficiencia Cardíaca/metabolismo , Masculino , Ratones , Miocitos Cardíacos/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The mRNAs stored in oocytes undergo general decay during the maternal-zygotic transition (MZT), and their stability is tightly interconnected with meiotic cell-cycle progression. However, the factors that trigger decay of maternal mRNA and couple this event to oocyte meiotic maturation remain elusive. Here, we identified B-cell translocation gene-4 (BTG4) as an MZT licensing factor in mice. BTG4 bridged CNOT7, a catalytic subunit of the CCR4-NOT deadenylase, to eIF4E, a key translation initiation factor, and facilitated decay of maternal mRNA. Btg4-null females produced morphologically normal oocytes but were infertile, owing to early developmental arrest. The intrinsic MAP kinase cascade in oocytes triggered translation of Btg4 mRNA stored in fully grown oocytes by targeting the 3' untranslated region, thereby coupling CCR4-NOT deadenylase-mediated decay of maternal mRNA with oocyte maturation and fertilization. This is a key step in oocyte cytoplasmic maturation that determines the developmental potential of mammalian embryos.
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Proteínas de Ciclo Celular/fisiología , Oocitos/fisiología , Regiones no Traducidas 3' , Animales , Secuencia de Bases , Células Cultivadas , Factor 4E Eucariótico de Iniciación/fisiología , Exorribonucleasas , Femenino , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Sistema de Señalización de MAP Quinasas , Masculino , Meiosis , Ratones Endogámicos ICR , Ratones Noqueados , Proteínas/metabolismo , Estabilidad del ARN , Proteínas Represoras , RibonucleasasRESUMEN
In early mammalian embryos, the genome is transcriptionally quiescent until the zygotic genome activation (ZGA) which occurs 2-3 days after fertilization. Despite a long-standing effort, maternal transcription factors regulating this crucial developmental event remain largely elusive. Here, using maternal and paternal mouse models of Yap1 deletion, we show that maternally accumulated yes-associated protein (YAP) in oocyte is essential for ZGA. Maternal Yap1-knockout embryos exhibit a prolonged two-cell stage and develop into the four-cell stage at a much slower pace than the wild-type controls. Transcriptome analyses identify YAP target genes in early blastomeres; two of which, Rpl13 and Rrm2, are required to mediate maternal YAP's effect in conferring developmental competence on preimplantation embryos. Furthermore, the physiological YAP activator, lysophosphatidic acid, can substantially improve early development of wild-type, but not maternal Yap1-knockout embryos in both oviduct and culture. These observations provide insights into the mechanisms of ZGA, and suggest potentials of YAP activators in improving the developmental competence of cultured embryos in assisted human reproduction and animal biotechnology.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Oocitos/metabolismo , Fosfoproteínas/metabolismo , Cigoto/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Proteínas de Ciclo Celular , Células Cultivadas , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/efectos de los fármacos , Genoma , Células HEK293 , Humanos , Lisofosfolípidos/farmacología , Ratones , Fosfoproteínas/genética , Proteínas Señalizadoras YAPRESUMEN
DNA double-strand breaks (DSBs) are one of the most cytotoxic types of DNA lesion challenging genome integrity. The activity of cyclin-dependent kinase Cdk1 is essential for DSB repair by homologous recombination and for DNA damage signaling. Here we identify the Fun30 chromatin remodeler as a new target of Cdk1. Fun30 is phosphorylated by Cdk1 on Serine 28 to stimulate its functions in DNA damage response including resection of DSB ends. Importantly, Cdk1-dependent phosphorylation of Fun30-S28 increases upon DNA damage and requires the recruitment of Fun30 to DSBs, suggesting that phosphorylation increases in situ at the DNA damage. Consistently, we find that Cdk1 and multiple cyclins become highly enriched at DSBs and that the recruitment of Cdk1 and cyclins Clb2 and Clb5 ensures optimal Fun30 phosphorylation and checkpoint activation. We propose that the enrichment of Cdk1-cyclin complexes at DSBs serves as a mechanism for enhanced targeting and modulating of the activity of DNA damage response proteins.
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Proteína Quinasa CDC2/genética , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades/genética , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Proteína Quinasa CDC2/metabolismo , Cromatina/química , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina , Ciclina B/genética , Ciclina B/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Datos de Secuencia Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alineación de Secuencia , Serina/metabolismo , Factores de Transcripción/metabolismoRESUMEN
In mammals, ovulation is a multistep physiological process that includes preovulatory follicle growth, oocyte meiotic maturation, cumulus-oocyte complex (COC) expansion, follicle rupture, and luteinization. TGF-ß signaling pathway has multiple functions in mammalian ovary, as its complexity in ovarian function has been demonstrated by mouse models with knockouts of TGF-ß receptors and SMADs. We describe the protocol that we use to study functions of TGF-ß signaling pathway in follicle development and ovulation. Because total knockout of TGF-ß pathway components often causes embryonic lethality, which prevents further investigation of these genes in ovarian functions, people have generated ovarian cell type-specific knockout mouse strains for TGF-ß signaling pathway genes. These mouse models are also described.
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Ovario/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Animales , Técnicas de Cultivo de Célula , Femenino , Hormona Folículo Estimulante/farmacología , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Hormona Luteinizante/farmacología , Ratones , Ratones Noqueados , Microscopía Confocal , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Ovulación/fisiología , Transducción de Señal/efectos de los fármacosRESUMEN
The duration of a woman's reproductive period is determined by the size and persistence of a dormant oocyte pool. Specific oocyte genes are essential for follicle maintenance and female fertility. The mechanisms that regulate the expression of these genes are poorly understood. We found that a cullin-ring finger ligase-4 (CRL4) complex was crucial in this process. Oocyte-specific deletion of the CRL4 linker protein DDB1 or its substrate adaptor VPRBP (also known as DCAF1) caused rapid oocyte loss, premature ovarian insufficiency, and silencing of fertility maintaining genes. CRL4(VPRBP) activates the TET methylcytosine dioxygenases, which are involved in female germ cell development and zygote genome reprogramming. Hence, CRL4(VPRBP) ubiquitin ligase is a guardian of female reproductive life in germ cells and a maternal reprogramming factor after fertilization.
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Proteínas Portadoras/metabolismo , Reprogramación Celular/genética , Proteínas de Unión al ADN/metabolismo , Dioxigenasas/metabolismo , Fertilidad/genética , Oocitos/fisiología , Proteínas Proto-Oncogénicas/metabolismo , Animales , Proteínas Portadoras/genética , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Proteínas de Unión al ADN/genética , Dioxigenasas/genética , Femenino , Silenciador del Gen , Disgenesia Gonadal/genética , Células HeLa , Humanos , Ratones , Ratones Noqueados , Oxigenasas de Función Mixta , Ovario/fisiopatología , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas/genéticaRESUMEN
Cullin-RING ubiquitin ligases (CRLs) are the largest family of E3 ligases and require cullin neddylation for their activation. The NEDD8-activating enzyme inhibitor MLN4924 reportedly blocked cullin neddylation and inactivated CRLs, which resulted in apoptosis induction and tumor suppression. However, CRL roles in ovarian cancer cell survival and the ovarian tumor repressing effects of MLN4924 are unknown. We show here that CRL4 components are highly expressed in human epithelial ovarian cancer tissues. MLN4924-induced DNA damage, cell cycle arrest, and apoptosis in ovarian cancer cells in a time- and dose-dependent manner. In addition, MLN4924 sensitized ovarian cancer cells to other chemotherapeutic drug treatments. Depletion of CRL4 components Roc1/2, Cul4a, and DDB1 had inhibitory effects on ovarian cancer cells similar to MLN4924 treatment, which suggested that CRL4 inhibition contributed to the chemotherapeutic effect of MLN4924 in ovarian cancers. We also investigated for key CRL4 substrate adaptors required for ovarian cancer cells. Depleting Vprbp/Dcaf1 did not significantly affect ovarian cancer cell growth, even though it was expressed by ovarian cancer tissues. However, depleting Cdt2/Dcaf2 mimicked the pharmacological effects of MLN4924 and caused the accumulation of its substrate, CDT1, both in vitro and in vivo. MLN4924-induced DNA damage and apoptosis were partially rescued by Cdt1 depletion, suggesting that CRL4(CDT2) repression and CDT1 accumulation were key biochemical events contributing to the genotoxic effects of MLN4924 in ovarian cancer cells. Taken together, these results indicate that CRL4(CDT2) is a potential drug target in ovarian cancers and that MLN4924 may be an effective anticancer agent for targeted ovarian cancer therapy.
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Ciclopentanos/farmacología , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Proteínas Nucleares/genética , Neoplasias Ováricas/tratamiento farmacológico , Pirimidinas/farmacología , Ubiquitina-Proteína Ligasas/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Western Blotting , Carcinoma Epitelial de Ovario , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Daño del ADN , Relación Dosis-Respuesta a Droga , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Ratones , Ratones Desnudos , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Glandulares y Epiteliales/patología , Proteínas Nucleares/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
BACKGROUND: The role of DAXX in ovarian cancer development and metastasis has not been investigated before now. RESULTS: Overexpression of DAXX enhanced ovarian cancer cell proliferation, colony formation, and migration, whereas Daxx depletion had the opposite effects. CONCLUSION: DAXX promotes ovarian cancer cell proliferation and chemoresistance. SIGNIFICANCE: ModulatingDAXXmay be an effective strategy for preventing the recurrence and chemoresistance of ovarian cancers. Understanding the genes involved in apoptosis and DNA damage responses may improve therapeutic strategies for ovarian cancer. The death domain-associated protein DAXX can be either a pro-apoptotic or an anti-apoptotic factor, depending on the cell type and context. In this study, we found that DAXX was highly expressed in human ovarian surface epithelial tumors but not in granulosa cell tumors. In cultured ovarian cancer cells, DAXX interacted with promyelocytic leukemia protein (PML) and localized to subnuclear domains (so-called PML nuclear bodies). A role for DAXX in ovarian cancer cell proliferation, metastasis, and radio/chemoresistance was examined. Overexpression of DAXX enhanced multiple ovarian cancer cell lines' proliferation, colony formation, and migration, whereas Daxx depletion by RNA interference had the opposite effects. When transplanted into nude mice, ovarian cancer cells that overexpressed DAXX displayed enhanced tumorigenesis capability in vivo, whereas Daxx depletion inhibited tumor development. Importantly, Daxx induced tumorigenic transformation of normal ovarian surface epithelial cells. Daxx also protected ovarian cancer cells against x-irradiation- and chemotherapy-induced DNA damage by interacting with PML. Taken together, our results suggest that DAXX is a novel ovarian cancer oncogene that promotes ovarian cancer cell proliferation and chemoresistance in ovarian cancer cells. Thus, modulating DAXX-PML nuclear body activity may be an effective strategy for preventing the recurrence and chemoresistance of ovarian cancers.