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1.
Cell ; 185(5): 860-871.e13, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-35120603

RESUMEN

The SARS-CoV-2 Omicron variant with increased fitness is spreading rapidly worldwide. Analysis of cryo-EM structures of the spike (S) from Omicron reveals amino acid substitutions forging interactions that stably maintain an active conformation for receptor recognition. The relatively more compact domain organization confers improved stability and enhances attachment but compromises the efficiency of the viral fusion step. Alterations in local conformation, charge, and hydrophobic microenvironments underpin the modulation of the epitopes such that they are not recognized by most NTD- and RBD-antibodies, facilitating viral immune escape. Structure of the Omicron S bound with human ACE2, together with the analysis of sequence conservation in ACE2 binding region of 25 sarbecovirus members, as well as heatmaps of the immunogenic sites and their corresponding mutational frequencies, sheds light on conserved and structurally restrained regions that can be used for the development of broad-spectrum vaccines and therapeutics.


Asunto(s)
Evasión Inmune/fisiología , SARS-CoV-2/fisiología , Glicoproteína de la Espiga del Coronavirus/química , Enzima Convertidora de Angiotensina 2/química , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Antivirales/inmunología , Sitios de Unión , COVID-19/inmunología , COVID-19/patología , COVID-19/virología , Microscopía por Crioelectrón , Humanos , Mutagénesis Sitio-Dirigida , Pruebas de Neutralización , Unión Proteica , Dominios Proteicos/inmunología , Estructura Cuaternaria de Proteína , SARS-CoV-2/aislamiento & purificación , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Resonancia por Plasmón de Superficie , Acoplamiento Viral
2.
Cell ; 173(1): 221-233.e12, 2018 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-29551271

RESUMEN

Tandem zinc finger (ZF) proteins are the largest and most rapidly diverging family of DNA-binding transcription regulators in mammals. ZFP568 represses a transcript of placental-specific insulin like growth factor 2 (Igf2-P0) in mice. ZFP568 binds a 24-base pair sequence-specific element upstream of Igf2-P0 via the eleven-ZF array. Both DNA and protein conformations deviate from the conventional one finger-three bases recognition, with individual ZFs contacting 2, 3, or 4 bases and recognizing thymine on the opposite strand. These interactions arise from a shortened minor groove caused by an AT-rich stretch, suggesting adaptability of ZF arrays to sequence variations. Despite conservation in mammals, mutations at Igf2 and ZFP568 reduce their binding affinity in chimpanzee and humans. Our studies provide important insights into the evolutionary and structural dynamics of ZF-DNA interactions that play a key role in mammalian development and evolution.


Asunto(s)
ADN/metabolismo , Proteínas Nucleares/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Proteínas Portadoras/química , Proteínas Portadoras/clasificación , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , ADN/química , Humanos , Factor II del Crecimiento Similar a la Insulina/química , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , Ratones , Simulación de Dinámica Molecular , Proteínas Nucleares/química , Proteínas Nucleares/clasificación , Proteínas Nucleares/genética , Conformación de Ácido Nucleico , Pan troglodytes , Filogenia , Polimorfismo de Nucleótido Simple , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia
3.
Nature ; 603(7903): 919-925, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35090164

RESUMEN

Omicron (B.1.1.529), the most heavily mutated SARS-CoV-2 variant so far, is highly resistant to neutralizing antibodies, raising concerns about the effectiveness of antibody therapies and vaccines1,2. Here we examined whether sera from individuals who received two or three doses of inactivated SARS-CoV-2 vaccine could neutralize authentic Omicron. The seroconversion rates of neutralizing antibodies were 3.3% (2 out of 60) and 95% (57 out of 60) for individuals who had received 2 and 3 doses of vaccine, respectively. For recipients of three vaccine doses, the geometric mean neutralization antibody titre for Omicron was 16.5-fold lower than for the ancestral virus (254). We isolated 323 human monoclonal antibodies derived from memory B cells in triple vaccinees, half of which recognized the receptor-binding domain, and showed that a subset (24 out of 163) potently neutralized all SARS-CoV-2 variants of concern, including Omicron. Therapeutic treatments with representative broadly neutralizing monoclonal antibodies were highly protective against infection of mice with SARS-CoV-2 Beta (B.1.351) and Omicron. Atomic structures of the Omicron spike protein in complex with three classes of antibodies that were active against all five variants of concern defined the binding and neutralizing determinants and revealed a key antibody escape site, G446S, that confers greater resistance to a class of antibodies that bind on the right shoulder of the receptor-binding domain by altering local conformation at the binding interface. Our results rationalize the use of three-dose immunization regimens and suggest that the fundamental epitopes revealed by these broadly ultrapotent antibodies are rational targets for a universal sarbecovirus vaccine.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Células B de Memoria , SARS-CoV-2 , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/aislamiento & purificación , Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/aislamiento & purificación , Anticuerpos Antivirales/uso terapéutico , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Modelos Animales de Enfermedad , Humanos , Células B de Memoria/inmunología , Ratones , Pruebas de Neutralización , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología
4.
Proc Natl Acad Sci U S A ; 121(23): e2403726121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38805293

RESUMEN

The key of heterostructure is the combinations created by stacking various vdW materials, which can modify interlayer coupling and electronic properties, providing exciting opportunities for designer devices. However, this simple stacking does not create chemical bonds, making it difficult to fundamentally alter the electronic structure. Here, we demonstrate that interlayer interactions in heterostructures can be fundamentally controlled using hydrostatic pressure, providing a bonding method to modify electronic structures. By covering graphene with boron nitride and inducing an irreversible phase transition, the conditions for graphene lattice-matching bonding (IMB) were created. We demonstrate that the increased bandgap of graphene under pressure is well maintained in ambient due to the IMB in the interface. Comparison to theoretical modeling emphasizes the process of pressure-induced interfacial bonding, systematically generalizes, and predicts this model. Our results demonstrate that pressure can irreversibly control interlayer bonding, providing opportunities for high-pressure technology in ambient applications and IMB engineering in heterostructures.

5.
Proc Natl Acad Sci U S A ; 121(2): e2310763120, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38165928

RESUMEN

Habitat degradation and loss of genetic diversity are common threats faced by almost all of today's wild cats. Big cats, such as tigers and lions, are of great concern and have received considerable conservation attention through policies and international actions. However, knowledge of and conservation actions for small wild cats are lagging considerably behind. The black-footed cat, Felis nigripes, one of the smallest felid species, is experiencing increasing threats with a rapid reduction in population size. However, there is a lack of genetic information to assist in developing effective conservation actions. A de novo assembly of a high-quality chromosome-level reference genome of the black-footed cat was made, and comparative genomics and population genomics analyses were carried out. These analyses revealed that the most significant genetic changes in the evolution of the black-footed cat are the rapid evolution of sensory and metabolic-related genes, reflecting genetic adaptations to its characteristic nocturnal hunting and a high metabolic rate. Genomes of the black-footed cat exhibit a high level of inbreeding, especially for signals of recent inbreeding events, which suggest that they may have experienced severe genetic isolation caused by habitat fragmentation. More importantly, inbreeding associated with two deleterious mutated genes may exacerbate the risk of amyloidosis, the dominant disease that causes mortality of about 70% of captive individuals. Our research provides comprehensive documentation of the evolutionary history of the black-footed cat and suggests that there is an urgent need to investigate genomic variations of small felids worldwide to support effective conservation actions.


Asunto(s)
Felidae , Felis , Leones , Humanos , Animales , Felidae/genética , Genoma , Genómica
6.
Proc Natl Acad Sci U S A ; 121(25): e2400546121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38857407

RESUMEN

Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that C─C bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.

7.
Genome Res ; 33(3): 463-477, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37310928

RESUMEN

Structural variations (SVs) are a major contributor to genetic diversity and phenotypic variations, but their prevalence and functions in domestic animals are largely unexplored. Here we generated high-quality genome assemblies for 15 individuals from genetically diverse sheep breeds using Pacific Biosciences (PacBio) high-fidelity sequencing, discovering 130.3 Mb nonreference sequences, from which 588 genes were annotated. A total of 149,158 biallelic insertions/deletions, 6531 divergent alleles, and 14,707 multiallelic variations with precise breakpoints were discovered. The SV spectrum is characterized by an excess of derived insertions compared to deletions (94,422 vs. 33,571), suggesting recent active LINE expansions in sheep. Nearly half of the SVs display low to moderate linkage disequilibrium with surrounding single-nucleotide polymorphisms (SNPs) and most SVs cannot be tagged by SNP probes from the widely used ovine 50K SNP chip. We identified 865 population-stratified SVs including 122 SVs possibly derived in the domestication process among 690 individuals from sheep breeds worldwide. A novel 168-bp insertion in the 5' untranslated region (5' UTR) of HOXB13 is found at high frequency in long-tailed sheep. Further genome-wide association study and gene expression analyses suggest that this mutation is causative for the long-tail trait. In summary, we have developed a panel of high-quality de novo assemblies and present a catalog of structural variations in sheep. Our data capture abundant candidate functional variations that were previously unexplored and provide a fundamental resource for understanding trait biology in sheep.


Asunto(s)
Estudio de Asociación del Genoma Completo , Cola (estructura animal) , Animales , Ovinos/genética , Regiones no Traducidas 5' , Alelos , Fenotipo
8.
Mol Cell ; 69(3): 480-492.e7, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29395065

RESUMEN

Fatty acid oxidation (FAO) is crucial for cells to overcome metabolic stress by providing ATP and NADPH. However, the mechanism by which FAO is regulated in tumors remains elusive. Here we show that Nur77 is required for the metabolic adaptation of melanoma cells by protecting FAO. Glucose deprivation activates ERK2 to phosphorylate and induce Nur77 translocation to the mitochondria, where Nur77 binds to TPß, a rate-limiting enzyme in FAO. Although TPß activity is normally inhibited by oxidation under glucose deprivation, the Nur77-TPß association results in Nur77 self-sacrifice to protect TPß from oxidation. FAO is therefore able to maintain NADPH and ATP levels and prevent ROS increase and cell death. The Nur77-TPß interaction further promotes melanoma metastasis by facilitating circulating melanoma cell survival. This study demonstrates a novel regulatory function of Nur77 with linkage of the FAO-NADPH-ROS pathway during metabolic stress, suggesting Nur77 as a potential therapeutic target in melanoma.


Asunto(s)
Melanoma/metabolismo , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Animales , Supervivencia Celular/fisiología , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Células HEK293 , Humanos , Metabolismo de los Lípidos , Melanoma/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/metabolismo , Subunidad beta de la Proteína Trifuncional Mitocondrial/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo
9.
Nucleic Acids Res ; 52(D1): D871-D881, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37941154

RESUMEN

Large-scale genome-wide association studies (GWAS) have provided profound insights into complex traits and diseases. Yet, deciphering the fine-scale molecular mechanisms of how genetic variants manifest to cause the phenotypes remains a daunting task. Here, we present COLOCdb (https://ngdc.cncb.ac.cn/colocdb), a comprehensive genetic colocalization database by integrating more than 3000 GWAS summary statistics and 13 types of xQTL to date. By employing two representative approaches for the colocalization analysis, COLOCdb deposits results from three key components: (i) GWAS-xQTL, pair-wise colocalization between GWAS loci and different types of xQTL, (ii) GWAS-GWAS, pair-wise colocalization between the trait-associated genetic loci from GWASs and (iii) xQTL-xQTL, pair-wise colocalization between the genetic loci associated with molecular phenotypes in xQTLs. These results together represent the most comprehensive colocalization analysis, which also greatly expands the list of shared variants with genetic pleiotropy. We expect that COLOCdb can serve as a unique and useful resource in advancing the discovery of new biological mechanisms and benefit future functional studies.


Asunto(s)
Estudio de Asociación del Genoma Completo , Herencia Multifactorial , Estudio de Asociación del Genoma Completo/métodos , Herencia Multifactorial/genética , Sitios de Carácter Cuantitativo , Fenotipo , Pleiotropía Genética , Polimorfismo de Nucleótido Simple
10.
Nucleic Acids Res ; 52(D1): D909-D918, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37870433

RESUMEN

Diverse individuals age at different rates and display variable susceptibilities to tissue aging, functional decline and aging-related diseases. Centenarians, exemplifying extreme longevity, serve as models for healthy aging. The field of human aging and longevity research is rapidly advancing, garnering significant attention and accumulating substantial data in recent years. Omics technologies, encompassing phenomics, genomics, transcriptomics, proteomics, metabolomics and microbiomics, have provided multidimensional insights and revolutionized cohort-based investigations into human aging and longevity. Accumulated data, covering diverse cells, tissues and cohorts across the lifespan necessitates the establishment of an open and integrated database. Addressing this, we established the Human Aging and Longevity Landscape (HALL), a comprehensive multi-omics repository encompassing a diverse spectrum of human cohorts, spanning from young adults to centenarians. The core objective of HALL is to foster healthy aging by offering an extensive repository of information on biomarkers that gauge the trajectory of human aging. Moreover, the database facilitates the development of diagnostic tools for aging-related conditions and empowers targeted interventions to enhance longevity. HALL is publicly available at https://ngdc.cncb.ac.cn/hall/index.


Asunto(s)
Envejecimiento , Bases de Datos Factuales , Longevidad , Multiómica , Anciano de 80 o más Años , Humanos , Adulto Joven , Envejecimiento/genética , Biomarcadores , Susceptibilidad a Enfermedades , Genómica , Longevidad/genética
11.
Plant J ; 118(4): 1218-1231, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38323895

RESUMEN

Borneol, camphor, and bornyl acetate are highly promising monoterpenoids widely used in medicine, flavor, food, and chemical applications. Bornyl diphosphate (BPP) serves as a common precursor for the biosynthesis of these monoterpenoids. Although bornyl diphosphate synthase (BPPS) that catalyzes the cyclization of geranyl diphosphate (GPP) to BPP has been identified in multiple plants, the enzyme responsible for the hydrolysis of BPP to produce borneol has not been reported. Here, we conducted in vitro and in vivo functional characterization to identify the Nudix hydrolase WvNUDX24 from W. villosa, which specifically catalyzes the hydrolysis of BPP to generate bornyl phosphate (BP), and then BP forms borneol under the action of phosphatase. Subcellular localization experiments indicated that the hydrolysis of BPP likely occurs in the cytoplasm. Furthermore, site-directed mutagenesis experiments revealed that four critical residues (R84, S96, P98, and G99) for the hydrolysis activity of WvNUDX24. Additionally, the functional identification of phosphatidic acid phosphatase (PAP) demonstrated that WvPAP5 and WvPAP10 were able to hydrolyze geranylgeranyl diphosphate (GGPP) and farnesyl diphosphate (FPP) to generate geranylgeranyl phosphate (GGP) and farnesyl phosphate (FP), respectively, but could not hydrolyze BPP, GPP, and neryl diphosphate (NPP) to produce corresponding monophosphate products. These findings highlight the essential role of WvNUDX24 in the first step of BPP hydrolysis to produce borneol and provide genetic elements for the production of BPP-related terpenoids through plant metabolic engineering and synthetic biology.


Asunto(s)
Canfanos , Hidrolasas Nudix , Proteínas de Plantas , Pirofosfatasas , Pirofosfatasas/metabolismo , Pirofosfatasas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Canfanos/metabolismo , Brassicaceae/genética , Brassicaceae/enzimología , Brassicaceae/metabolismo , Fosfatos de Poliisoprenilo/metabolismo
12.
Exp Cell Res ; 439(1): 114089, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38740166

RESUMEN

Nucleus pulposus cells (NPCs) apoptosis and inflammation are the extremely critical factors of intervertebral disc degeneration (IVDD). Nevertheless, the underlying procedure remains mysterious. Macrophage migration inhibitory factor (MIF) is a cytokine that promotes inflammation and has been demonstrated to have a significant impact on apoptosis and inflammation. For this research, we employed a model of NPCs degeneration stimulated by lipopolysaccharides (LPS) and a rat acupuncture IVDD model to examine the role of MIF in vitro and in vivo, respectively. Initially, we verified that there was a significant rise of MIF expression in the NP tissues of individuals with IVDD, as well as in rat models of IVDD. Furthermore, this augmented expression of MIF was similarly evident in degenerated NPCs. Afterwards, it was discovered that ISO-1, a MIF inhibitor, effectively decreased the quantity of cells undergoing apoptosis and inhibited the release of inflammatory molecules (TNF-α, IL-1ß, IL-6). Furthermore, it has been shown that the PI3K/Akt pathway plays a vital part in the regulation of NPCs degeneration by MIF. Ultimately, we showcased that the IVDD process was impacted by the MIF inhibitor in the rat model. In summary, our experimental results substantiate the significant involvement of MIF in the degeneration of NPCs, and inhibiting MIF activity can effectively mitigate IVDD.


Asunto(s)
Apoptosis , Inflamación , Degeneración del Disco Intervertebral , Factores Inhibidores de la Migración de Macrófagos , Núcleo Pulposo , Ratas Sprague-Dawley , Animales , Factores Inhibidores de la Migración de Macrófagos/antagonistas & inhibidores , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patología , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/metabolismo , Apoptosis/efectos de los fármacos , Inflamación/metabolismo , Inflamación/patología , Ratas , Masculino , Humanos , Oxidorreductasas Intramoleculares/metabolismo , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Femenino , Isoxazoles/farmacología , Adulto , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Fosfatidilinositol 3-Quinasas/metabolismo
13.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38889442

RESUMEN

Neurofeedback, a non-invasive intervention, has been increasingly used as a potential treatment for major depressive disorders. However, the effectiveness of neurofeedback in alleviating depressive symptoms remains uncertain. To address this gap, we conducted a comprehensive meta-analysis to evaluate the efficacy of neurofeedback as a treatment for major depressive disorders. We conducted a comprehensive meta-analysis of 22 studies investigating the effects of neurofeedback interventions on depression symptoms, neurophysiological outcomes, and neuropsychological function. Our analysis included the calculation of Hedges' g effect sizes and explored various moderators like intervention settings, study designs, and demographics. Our findings revealed that neurofeedback intervention had a significant impact on depression symptoms (Hedges' g = -0.600) and neurophysiological outcomes (Hedges' g = -0.726). We also observed a moderate effect size for neurofeedback intervention on neuropsychological function (Hedges' g = -0.418). As expected, we observed that longer intervention length was associated with better outcomes for depressive symptoms (ß = -4.36, P < 0.001) and neuropsychological function (ß = -2.89, P = 0.003). Surprisingly, we found that shorter neurofeedback sessions were associated with improvements in neurophysiological outcomes (ß = 3.34, P < 0.001). Our meta-analysis provides compelling evidence that neurofeedback holds promising potential as a non-pharmacological intervention option for effectively improving depressive symptoms, neurophysiological outcomes, and neuropsychological function in individuals with major depressive disorders.


Asunto(s)
Trastorno Depresivo Mayor , Neurorretroalimentación , Neurorretroalimentación/métodos , Humanos , Trastorno Depresivo Mayor/terapia , Trastorno Depresivo Mayor/fisiopatología , Resultado del Tratamiento , Electroencefalografía/métodos
14.
Nucleic Acids Res ; 51(19): 10309-10325, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37697430

RESUMEN

Krüppel-associated box zinc finger proteins (KZFPs) function as a defense mechanism to maintain the genome stability of higher vertebrates by regulating the transcriptional activities of transposable elements (TEs). While previous studies have characterized ZFP809 as responsible for binding and repressing ERVs containing a proline tRNA primer-binding site (PBS-Pro) in mice, comparable KZFPs have not been identified in humans yet. Here, we identified ZNF506 as a PBS-Pro-binding protein in humans, which functions as a transcriptional repressor of PBS-Pro-utilizing retroviruses by recruiting heterochromatic modifications. Although they have similar functions, the low protein similarities between ZNF506, ZFP809 and KZFPs of other species suggest their independent evolution against the invasion of PBS-Pro-utilizing retroviruses into their respective ancestor genomes after species divergence. We also explored the link between ZNF506 and leukemia. Our findings suggest that ZNF506 is a unique human KZFP that can bind to PBS-Pro, highlighting the diverse evolution of KZFPs in defending against retroviral invasions. Additionally, our study provides insights into the potential role of ZNF506 in leukemia, contributing to the expanding knowledge of KZFPs' crucial function in disease and genome stability.


Asunto(s)
Retrovirus Endógenos , Leucemia , Animales , Humanos , Ratones , Sitios de Unión , Retrovirus Endógenos/genética , Retrovirus Endógenos/metabolismo , Inestabilidad Genómica , Leucemia/genética , Proteínas Represoras/metabolismo
15.
Proc Natl Acad Sci U S A ; 119(11): e2119415119, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35259018

RESUMEN

SignificanceHosts often target the relatively conserved regions in rapidly mutating retroviruses to inhibit their replication. One of these regions is called a primer binding site (PBS), which has to be complementary to the host tRNA to initiate reverse transcription. By analyzing endogenous retroviral elements, we found that host cells use this sequence as a target in efforts to block the expression of viral elements. A specific type of zinc finger protein targets the PBS in a host genome, which not only inhibits the transcription of endogenous viruses but also inhibits the replication of exogenous retroviruses with the same PBS. Thus, our study sheds light on a strategy for searching for host restriction factors targeting retroviruses.


Asunto(s)
Regulación Viral de la Expresión Génica , Interacciones Huésped-Patógeno , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Represoras/metabolismo , Retroviridae/fisiología , Dedos de Zinc , Secuencia de Bases , Sitios de Unión , Mapeo Cromosómico , Retrovirus Endógenos , Estudio de Asociación del Genoma Completo , Humanos , Motivos de Nucleótidos , Retroviridae/clasificación , Transcripción Genética , Replicación Viral
16.
Chem Soc Rev ; 53(3): 1514-1551, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38167899

RESUMEN

Protein-based bioactive coatings have emerged as a versatile and promising strategy for enhancing the performance and biocompatibility of diverse biomedical materials and devices. Through surface modification, these coatings confer novel biofunctional attributes, rendering the material highly bioactive. Their widespread adoption across various domains in recent years underscores their importance. This review systematically elucidates the behavior of protein-based bioactive coatings in organisms and expounds on their underlying mechanisms. Furthermore, it highlights notable advancements in artificial synthesis methodologies and their functional applications in vitro. A focal point is the delineation of assembly strategies employed in crafting protein-based bioactive coatings, which provides a guide for their expansion and sustained implementation. Finally, the current trends, challenges, and future directions of protein-based bioactive coatings are discussed.


Asunto(s)
Materiales Biocompatibles Revestidos
17.
J Am Chem Soc ; 146(12): 8768-8779, 2024 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-38483318

RESUMEN

2'-Deoxynucleosides and analogues play a vital role in drug development, but their preparation remains a significant challenge. Previous studies have focused on ß-2'-deoxynucleosides with the natural ß-configuration. In fact, their isomeric α-2'-deoxynucleosides also exhibit diverse bioactivities and even better metabolic stability. Herein, we report that both α- and ß-2'-deoxynucleosides can be prepared with high yields and stereoselectivity using a remote directing diphenylphosphinoyl (DPP) group. It is particularly efficient to prepare α-2'-deoxynucleosides with an easily accessible 3,5-di-ODPP donor. Instead of acting as a H-bond acceptor on a 2-(diphenylphosphinoyl)acetyl (DPPA) group in our previous studies for syn-facial O-glycosylation, the phosphine oxide moiety here acts as a remote participating group to enable highly antifacial N-glycosylation. This proposed remote participation mechanism is supported by our first characterization of an important 1,5-briged P-heterobicyclic intermediate via variable-temperature NMR spectroscopy. Interestingly, antiproliferative assays led to a α-2'-deoxynucleoside with IC50 values in the low micromole range against central nervous system tumor cell lines SH-SY5Y and LN229, whereas its ß-anomer exhibited no inhibition at 100 µM. Furthermore, the DPP group significantly enhanced the antitumor activities by 10 times.


Asunto(s)
Neuroblastoma , Fosfinas , Humanos , Glicosilación
18.
Cancer Sci ; 115(6): 1910-1923, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558246

RESUMEN

Chemoresistance is a major cause of high mortality and poor survival in patients with ovarian cancer (OVCA). Understanding the mechanisms of chemoresistance is urgently required to develop effective therapeutic approaches to OVCA. Here, we show that expression of the long noncoding RNA, taurine upregulated gene 1 (TUG1), is markedly upregulated in samples from OVCA patients who developed resistance to primary platinum-based therapy. Depletion of TUG1 increased sensitivity to cisplatin in the OVCA cell lines, SKOV3 and KURAMOCHI. Combination therapy of cisplatin with antisense oligonucleotides targeting TUG1 coupled with a drug delivery system effectively relieved the tumor burden in xenograft mouse models. Mechanistically, TUG1 acts as a competing endogenous RNA by downregulating miR-4687-3p and miR-6088, both of which target DNA polymerase eta (POLH), an enzyme required for translesion DNA synthesis. Overexpression of POLH reversed the effect of TUG1 depletion on cisplatin-induced cytotoxicity. Our data suggest that TUG1 upregulation allows OVCA to tolerate DNA damage via upregulation of POLH; this provides a strong rationale for targeting TUG1 to overcome cisplatin resistance in OVCA.


Asunto(s)
Cisplatino , ADN Polimerasa Dirigida por ADN , Resistencia a Antineoplásicos , Neoplasias Ováricas , ARN Largo no Codificante , Animales , Femenino , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Cisplatino/farmacología , Cisplatino/uso terapéutico , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones Desnudos , MicroARNs/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , ARN Largo no Codificante/genética , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Anal Chem ; 96(18): 7194-7203, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38656822

RESUMEN

To obtain enhanced physical and biological properties, various nanoparticles are typically assembled into hybrid nanoparticles through the binding of multiple homologous DNA strands to their complementary counterparts, commonly referred to as homomultivalent assembly. However, the poor binding affinity and limited controllability of homomultivalent disassembly restrict the assembly yield and dynamic functionality of the hybrid nanoparticles. To achieve a higher binding affinity and flexible assembly choice, we utilized the paired heteromultivalency DNA to construct hybrid nanoparticles and demonstrate their excellent assembly characteristics and dynamic applications. Specifically, through heteromultivalency, DNA-functionalized magnetic beads (MBs) and gold nanoparticles (AuNPs) were efficiently assembled. By utilizing ICP-MS, the assembly efficiency of AuNPs on MBs was directly monitored, enabling quantitative analysis and optimization of heteromultivalent binding events. As a result, the enhanced assembly yield is primarily attributed to the fact that heteromultivalency allows for the maximization of effective DNA probes on the surface of nanoparticles, eliminating steric hindrance interference. Subsequently, with external oligonucleotides as triggers, it was revealed that the disassembly mechanism of hybrid nanoparticles was initiated, which was based on an increased local concentration rather than toehold-mediated displacement of paired heteromultivalency DNA probes. Capitalizing on these features, an output platform was then established based on ICP-MS signals that several Boolean operations and analytical applications can be achieved by simply modifying the design sequences. The findings provide new insights into DNA biointerface interaction, with potential applications to complex logic operations and the construction of large DNA nanostructures.


Asunto(s)
ADN , Oro , Espectrometría de Masas , Nanopartículas del Metal , Oro/química , ADN/química , Nanopartículas del Metal/química
20.
Anal Chem ; 96(26): 10851-10859, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38912707

RESUMEN

Mitochondrial Membrane Chromatography (MMC) is a bioaffinity chromatography technique developed to study the interaction between target proteins embedded in the mitochondrial membrane and their ligand compounds. However, the MMC stationary phases (MMSP) prepared by chemical immobilization are prone to nonspecific binding in candidate agent screening inevitably. To address these challenges, Twin Strep-Tag/Strep Tactin was employed to establish a specific affinity system in the present study. We prepared a carnitine palmitoyltransferase 1A (CPT1A) MMSP by specifically linking Strep-tactin-modified silica gel with the Twin Strep-Tag on the CPT1A-oriented mitochondrial membrane. This Twin Strep-Tag/Strep Tactin modified CPT1A/MMC method exhibited remarkably better retention behavior, longer stationary phase lifespan, and higher screening specificity compared with previous MMC systems with glutaraldehyde immobilization. We adopted the CPT1A-specific MMC system in screening CPT1A ligands from traditional Chinese medicines, and successfully identified novel candidate ligands: ononin, isoliquiritigenin, and aloe-emodin, from Glycyrrhiza uralensis Fisch and Senna tora (L.) Roxb extracts. Biological assessments illustrated that the compounds screened promote CPT1A enzyme activity without affecting CPT1A protein expression, as well as effectively reduce the lipid droplets and triglyceride levels in the high fat induction HepG2 cells. The results suggest that we have developed an MMC system, which is promising for studying the bioaffinity of mitochondrial membrane proteins to candidate compounds. This system provides a platform for a key step in mitochondrial medicine discovery, especially for bioactive molecule screening from complex herbal extracts.


Asunto(s)
Carnitina O-Palmitoiltransferasa , Metabolismo de los Lípidos , Membranas Mitocondriales , Humanos , Carnitina O-Palmitoiltransferasa/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Cromatografía de Afinidad , Ligandos
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