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1.
Nat Immunol ; 24(2): 280-294, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36543960

RESUMEN

T cell dysfunctionality prevents the clearance of chronic infections and cancer. Furthermore, epigenetic programming in dysfunctional CD8+ T cells limits their response to immunotherapies, including immune checkpoint blockade (ICB). However, it is unclear which upstream signals drive acquisition of dysfunctional epigenetic programs, and whether therapeutically targeting these signals can remodel terminally dysfunctional T cells to an ICB-responsive state. Here we innovate an in vitro model system of stable human T cell dysfunction and show that chronic TGFß1 signaling in posteffector CD8+ T cells accelerates their terminal dysfunction through stable epigenetic changes. Conversely, boosting bone morphogenetic protein (BMP) signaling while blocking TGFß1 preserved effector and memory programs in chronically stimulated human CD8+ T cells, inducing superior responses to tumors and synergizing the ICB responses during chronic viral infection. Thus, rebalancing TGFß1/BMP signals provides an exciting new approach to unleash dysfunctional CD8+ T cells and enhance T cell immunotherapies.


Asunto(s)
Linfocitos T CD8-positivos , Virosis , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia , Transducción de Señal , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo
2.
Nat Chem Biol ; 20(1): 42-51, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37563455

RESUMEN

Protein lipidation, which regulates numerous biological pathways and plays crucial roles in the pharmaceutical industry, is not encoded by the genetic code but synthesized post-translationally. In the present study, we report a computational approach for designing lipidation mimics that fully recapitulate the biochemical properties of natural lipidation in membrane association and albumin binding. Furthermore, we establish an engineered system for co-translational incorporation of these lipidation mimics into virtually any desired position of proteins in Escherichia coli and mammalian cells. We demonstrate the utility of these length-tunable lipidation mimics in diverse applications, including improving the half-life and activity of therapeutic proteins in living mice, anchoring functional proteins to membrane by substituting natural lipidation, functionally characterizing proteins carrying different lengths of lipidation and determining the plasma membrane-binding capacity of a given compound. Our strategy enables gain-of-function studies of lipidation in hundreds of proteins and facilitates the creation of superior therapeutic candidates.


Asunto(s)
Mamíferos , Proteínas , Ratones , Animales , Proteínas/química , Membrana Celular/metabolismo
3.
Nature ; 586(7831): 702-707, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33116291

RESUMEN

The discoveries of intrinsically magnetic topological materials, including semimetals with a large anomalous Hall effect and axion insulators1-3, have directed fundamental research in solid-state materials. Topological quantum chemistry4 has enabled the understanding of and the search for paramagnetic topological materials5,6. Using magnetic topological indices obtained from magnetic topological quantum chemistry (MTQC)7, here we perform a high-throughput search for magnetic topological materials based on first-principles calculations. We use as our starting point the Magnetic Materials Database on the Bilbao Crystallographic Server, which contains more than 549 magnetic compounds with magnetic structures deduced from neutron-scattering experiments, and identify 130 enforced semimetals (for which the band crossings are implied by symmetry eigenvalues), and topological insulators. For each compound, we perform complete electronic structure calculations, which include complete topological phase diagrams using different values of the Hubbard potential. Using a custom code to find the magnetic co-representations of all bands in all magnetic space groups, we generate data to be fed into the algorithm of MTQC to determine the topology of each magnetic material. Several of these materials display previously unknown topological phases, including symmetry-indicated magnetic semimetals, three-dimensional anomalous Hall insulators and higher-order magnetic semimetals. We analyse topological trends in the materials under varying interactions: 60 per cent of the 130 topological materials have topologies sensitive to interactions, and the others have stable topologies under varying interactions. We provide a materials database for future experimental studies and open-source code for diagnosing topologies of magnetic materials.

4.
Circulation ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39229700

RESUMEN

BACKGROUND: Renal denervation (RDN) can lower blood pressure (BP) in patients with hypertension in both the presence and absence of medication. This is the first sham-controlled trial investigating the safety and efficacy of RDN in China. METHODS: This prospective, multicenter, randomized, patient- and outcome-assessor-blinded, sham-controlled trial investigated radiofrequency RDN in patients with hypertension on standardized triple antihypertensive therapy. Eligible patients were randomized 1:1 to undergo RDN using a multi-electrode radiofrequency catheter (Iberis; AngioCare, Shanghai, China) or a sham procedure. The primary efficacy outcome was the between-group difference in baseline-adjusted change in mean 24-hour ambulatory systolic BP from randomization to 6 months. RESULTS: Of 217 randomized patients (mean age, 45.3±10.2 years; 21% female), 107 were randomized to RDN and 110 were randomized to sham control. At 6 months, there was a greater reduction in 24-hour systolic BP in the RDN (-13.0±12.1 mm Hg) compared with the sham control group (-3.0±13.0 mm Hg; baseline-adjusted between-group difference, -9.4 mm Hg [95% CI, -12.8 to -5.9]; P<0.001). Compared with sham, 24-hour diastolic BP was lowered by -5.0 mm Hg ([95% CI, -7.5 to -2.4]; P<0.001) 6 months after RDN, and office systolic and diastolic BP was lowered by -6.4 mm Hg ([95% CI, -10.5 to -2.3]; P=0.003) and -5.1 mm Hg ([95% CI, -8.2 to -2.0]; P=0.001), respectively. One patient in the RDN group experienced an access site complication (hematoma), which resolved without sequelae. No other major device- or procedure-related safety events occurred through follow-up. CONCLUSIONS: In this trial of Chinese patients with uncontrolled hypertension on a standardized triple pharmacotherapy, RDN was safe and reduced ambulatory and office BP at 6 months compared with sham. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT02901704.

5.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37537355

RESUMEN

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

6.
J Pathol ; 264(3): 250-269, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39161125

RESUMEN

Testicular tumors represent the most common malignancy among young men. Nevertheless, the pathogenesis and molecular underpinning of testicular tumors remain largely elusive. We aimed to delineate the intricate intra-tumoral heterogeneity and the network of intercellular communication within the tumor microenvironment. A total of 40,760 single-cell transcriptomes were analyzed, encompassing samples from six individuals with seminomas, two patients with mixed germ cell tumors, one patient with a Leydig cell tumor, and three healthy donors. Five distinct malignant subclusters were identified in the constructed landscape. Among them, malignant 1 and 3 subclusters were associated with a more immunosuppressive state and displayed worse disease-free survival. Further analysis identified that APP-CD74 interactions were significantly strengthened between malignant 1 and 3 subclusters and 14 types of immune subpopulations. In addition, we established an aberrant spermatogenesis trajectory and delineated the global gene alterations of somatic cells in seminoma testes. Sertoli cells were identified as the somatic cell type that differed the most from healthy donors to seminoma testes. Cellular communication between spermatogonial stem cells and Sertoli cells is disturbed in seminoma testes. Our study delineates the intra-tumoral heterogeneity and the tumor immune microenvironment in testicular tumors, offering novel insights for targeted therapy. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de la Célula Individual , Neoplasias Testiculares , Microambiente Tumoral , Humanos , Masculino , Neoplasias Testiculares/genética , Neoplasias Testiculares/patología , Neoplasias Testiculares/inmunología , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Perfilación de la Expresión Génica/métodos , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase II/metabolismo , Transcriptoma , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Seminoma/genética , Seminoma/patología , Seminoma/inmunología , Tolerancia Inmunológica/genética , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias de Células Germinales y Embrionarias/inmunología , Antígenos de Diferenciación de Linfocitos B
7.
Nano Lett ; 24(32): 9832-9838, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39101565

RESUMEN

The surface of three-dimensional materials provides an ideal and versatile platform to explore quantum-confined physics. Here, we systematically investigate the electronic structure of Na-intercalated CrTe2, a van der Waals antiferromagnet, using angle-resolved photoemission spectroscopy and ab initio calculations. The measured band structure deviates from the calculation of bulk NaCrTe2 but agrees with that of ferromagnetic monolayer CrTe2. Consistently, we observe unexpected exchange splitting of the band dispersions, persisting well above the Néel temperature of bulk NaCrTe2. We argue that NaCrTe2 features a quantum-confined 2D ferromagnetic state in the topmost surface layer due to strong ferromagnetic correlation in the CrTe2 layer. Moreover, the exchange splitting and the critical temperature can be controlled by surface doping of alkali-metal atoms, suggesting the feasibility of tuning the surface ferromagnetism. Our work not only presents a simple platform for exploring tunable 2D ferromagnetism but also provides important insights into the quantum-confined low-dimensional magnetic states.

8.
Nano Lett ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39361493

RESUMEN

Time reversal symmetry breaking in superconductors, resulting from external magnetic fields or spontaneous magnetization, often leads to unconventional superconducting properties. In this way, an intrinsic phenomenon called the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state may be realized by the Zeeman effect. Here, we construct the FFLO state in an artificial CrOCl/NbSe2 van der Waals (vdW) heterostructure by utilizing the superconducting proximity effect of NbSe2 flakes. The proximity-induced superconductivity demonstrates a considerably weak gap of about 0.12 meV, and the in-plane upper critical field reveals the behavior of the FFLO state. First-principles calculations uncover the origin of the proximitized superconductivity, which indicates the importance of Cr vacancies or line defects in CrOCl. Moreover, the FFLO state could be induced by the inherent large spin splitting in CrOCl. Our findings not only provide a practical scheme for constructing the FFLO state but also inspire the discovery of an exotic FFLO state in other two-dimensional vdW heterostructures.

9.
J Biol Chem ; 299(8): 104942, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37343700

RESUMEN

The rapid advances in genome editing technologies have revolutionized the study of gene functions in cell or animal models. The recent generation of double-stranded DNA cleavage-independent base editors has been suitably adapted for interrogation of protein-coding genes on the basis of introducing premature stop codons or disabling the start codons. However, such versions of stop/start codon-oriented genetic tools still present limitations on their versatility, base-level precision, and target specificity. Here, we exploit a newly developed prime editor (PE) that differs from base editors by its adoption of a reverse transcriptase activity, which enables incorporation of various types of precise edits templated by a specialized prime editing guide RNA. Based on such a versatile platform, we established a prime editing-empowered method (PE-STOP) for installation of nonsense substitutions, providing a complementary approach to the present gene-targeting tools. PE-STOP is bioinformatically predicted to feature substantially expanded coverage in the genome space. In practice, PE-STOP introduces stop codons with good efficiencies in human embryonic kidney 293T and N2a cells (with medians of 29% [ten sites] and 25% [four sites] editing efficiencies, respectively), while exhibiting minimal off-target effects and high on-target precision. Furthermore, given the fact that PE installs prime editing guide RNA-templated mutations, we introduce a unique strategy for precise genetic rescue of PE-STOP-dependent nonsense mutation via the same PE platform. Altogether, the present work demonstrates a versatile and specific tool for gene inactivation and for functional interrogation of nonsense mutations.


Asunto(s)
Codón sin Sentido , Edición Génica , Animales , Humanos , Codón sin Sentido/genética , Codón de Terminación/genética , Edición Génica/métodos , Silenciador del Gen , Mutación , Línea Celular
10.
Acc Chem Res ; 56(20): 2827-2837, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37793174

RESUMEN

Protein post-translational modification (PTM) is a major mechanism for functional diversification of the human genome and plays a crucial role in almost every aspect of cellular processes, and the dysregulation of the protein PTM network has been associated with a variety of human diseases. Using high-resolution mass spectrometry, protein PTMs can be efficiently discovered and profiled under various biological and physiological conditions. However, it is often challenging to address the biological function of PTMs with biochemical and mutagenesis-based approaches. Specifically, this field lacks methods that allow gain-of-function studies of protein PTMs to understand their functional consequences in living cells. In this context, the genetic code expansion (GCE) strategy has made tremendous progress in the direct installation of PTMs and their analogs in the form of noncanonical amino acids (ncAAs) for gain-of-function investigations.In addition to studying the biological functions of known protein PTMs, the discovery of new protein PTMs is even more challenging due to the lack of chemical information for designing specific enrichment methods. Genetically encoded ncAAs in the proteome can be used as specific baits to enrich and subsequently identify new PTMs by mass spectrometry.In this Account, we discuss recent developments in the investigation of the biological functions of protein PTMs and the discovery of protein PTMs using new GCE strategies. First, we leveraged a chimeric design to construct several broadly orthogonal translation systems (OTSs). These broad OTSs can be engineered to efficiently incorporate different ncAAs in both E. coli and mammalian cells. With these broad OTSs, we accomplish the following: (1) We develop a computer-aided strategy for the design and genetic incorporation of length-tunable lipidation mimics. These lipidation mimics can fully recapitulate the biochemical properties of natural lipidation in membrane association for probing its biological functions on signaling proteins and in albumin binding for designing long-acting protein drugs. (2) We demonstrate that the binding affinity between histone methylations and their corresponding readers can be substantially increased with genetically encoded electron-rich Trp derivatives. These engineered affinity-enhanced readers can be applied to enrich, image, and profile the interactome of chromatin methylations. (3) We report the identification and verification of a novel type of protein PTM, aminoacylated lysine ubiquitination, using genetically encoded PTM ncAAs as chemical probes. This approach provides a general strategy for the identification of unknown PTMs by increasing the abundance of PTM bait probes.


Asunto(s)
Escherichia coli , Procesamiento Proteico-Postraduccional , Animales , Humanos , Escherichia coli/metabolismo , Proteoma , Código Genético , Espectrometría de Masas/métodos , Aminoácidos/genética , Aminoácidos/metabolismo , Mamíferos/metabolismo
11.
Blood ; 139(17): 2653-2665, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35231105

RESUMEN

Increasing evidence links metabolism, protein synthesis, and growth signaling to impairments in the function of hematopoietic stem and progenitor cells (HSPCs) during aging. The Lin28b/Hmga2 pathway controls tissue development, and the postnatal downregulation of this pathway limits the self-renewal of adult vs fetal hematopoietic stem cells (HSCs). Igf2bp2 is an RNA binding protein downstream of Lin28b/Hmga2, which regulates messenger RNA stability and translation. The role of Igf2bp2 in HSC aging is unknown. In this study, an analysis of wild-type and Igf2bp2 knockout mice showed that Igf2bp2 regulates oxidative metabolism in HSPCs and the expression of metabolism, protein synthesis, and stemness-related genes in HSCs of young mice. Interestingly, Igf2bp2 expression and function strongly declined in aging HSCs. In young mice, Igf2bp2 deletion mimicked aging-related changes in HSCs, including changes in Igf2bp2 target gene expression and impairment of colony formation and repopulation capacity. In aged mice, Igf2bp2 gene status had no effect on these parameters in HSCs. Unexpectedly, Igf2bp2-deficient mice exhibited an amelioration of the aging-associated increase in HSCs and myeloid-skewed differentiation. The results suggest that Igf2bp2 controls mitochondrial metabolism, protein synthesis, growth, and stemness of young HSCs, which is necessary for full HSC function during young adult age. However, Igf2bp2 gene function is lost during aging, and it appears to contribute to HSC aging in 2 ways: the aging-related loss of Igf2bp2 gene function impairs the growth and repopulation capacity of aging HSCs, and the activity of Igf2bp2 at a young age contributes to aging-associated HSC expansion and myeloid skewing.


Asunto(s)
Envejecimiento , Células Madre Hematopoyéticas , Proteínas de Unión al ARN , Envejecimiento/genética , Animales , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , Ratones , Ratones Noqueados , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
12.
J Exp Bot ; 75(11): 3300-3321, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38447063

RESUMEN

In a gene chip analysis, rice (Oryza sativa) OsSMP2 gene expression was induced under various abiotic stresses, prompting an investigation into its role in drought resistance and abscisic acid signaling. Subsequent experiments, including qRT-PCR and ß-glucuronidase activity detection, affirmed the OsSMP2 gene's predominant induction by drought stress. Subcellular localization experiments indicated the OsSMP2 protein primarily localizes to the cell membrane system. Overexpressing OsSMP2 increased sensitivity to exogenous abscisic acid, reducing drought resistance and leading to reactive oxygen species accumulation under drought stress. Conversely, in simulated drought experiments, OsSMP2-silenced transgenic plants showed significantly longer roots compared with the wild-type Nipponbare. These results suggest that OsSMP2 overexpression negatively affects rice drought resistance, offering valuable insights into molecular mechanisms, and highlight OsSMP2 as a potential target for enhancing crop resilience to drought stress.


Asunto(s)
Ácido Abscísico , Sequías , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Estrés Fisiológico , Oryza/genética , Oryza/fisiología , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ácido Abscísico/metabolismo , Plantas Modificadas Genéticamente , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética
13.
Appl Microbiol Biotechnol ; 108(1): 411, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980443

RESUMEN

This study investigates the dynamic changes in milk nutritional composition and microbial communities in Tibetan sheep and goats during the first 56 days of lactation. Milk samples were systematically collected at five time points (D0, D7, D14, D28, D56) post-delivery. In Tibetan sheep, milk fat, protein, and casein contents were highest on D0, gradually decreased, and stabilized after D14, while lactose and galactose levels showed the opposite trend. Goat milk exhibited similar initial peaks, with significant changes particularly between D0, D7, D14, and D56. 16S rRNA gene sequencing revealed increasing microbial diversity in both species over the lactation period. Principal coordinates analysis identified distinct microbial clusters corresponding to early (D0-D7), transitional (D14-D28), and mature (D56) stages. Core phyla, including Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, dominated the milk microbiota, with significant temporal shifts. Core microbes like Lactobacillus, Leuconostoc, and Streptococcus were common in both species, with species-specific taxa observed (e.g., Pediococcus in sheep, Shewanella in goats). Furthermore, we observed a highly shared core microbiota in sheep and goat milk, including Lactobacillus, Leuconostoc, and Streptococcus. Spearman correlation analysis highlighted significant relationships between specific microbial genera and milk nutrients. For instance, Lactobacillus positively correlated with total solids, non-fat milk solids, protein, and casein, while Mannheimia negatively correlated with protein content. This study underscores the complex interplay between milk composition and microbial dynamics in Tibetan sheep and goats, informing strategies for livestock management and nutritional enhancement. KEY POINTS: • The milk can be classified into three types based on the microbiota composition • The changes of milk microbiota are closely related to the variations in nutrition • Filter out microbiota with species specificity and age specificity in the milk.


Asunto(s)
Cabras , Microbiota , Leche , ARN Ribosómico 16S , Animales , Cabras/microbiología , Leche/microbiología , Leche/química , Ovinos/microbiología , ARN Ribosómico 16S/genética , Tibet , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Femenino , Lactancia , Caseínas , Proteínas de la Leche/análisis
14.
J Chem Phys ; 160(19)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38747437

RESUMEN

Zero-dimensional (0D) hybrid metal halides (HMHs) have emerged as a promising platform for exploring excitation-dependent multicolor luminescent materials owing to their diverse crystal structures and chemical compositions. Nevertheless, understanding the mechanism behind excitation-dependent emissions (EDEs) in 0D HMHs and achieving precise modulation remains challenging. In this work, the delicate regulations on the EDE of 0D (DMEDABr)4SnBr3I3 (DMEDA: N, N'-dimethylethylenediamine) with mixed halogens are achieved under low temperature and high pressure, respectively. The inhomogeneous halogen occupation at the atomic scale leads to the formation of Br-rich and I-rich SnX6 (X = Br, I) octahedra, which act as distinct luminescent centers upon photoexcitation. At low temperatures, the narrowed photoluminescence spectra could distinguish the individual emissions from different luminescent centers, resulting in a pronounced EDE of (DMEDABr)4SnBr3I3. In addition, the contraction and distortion of the luminescent SnX6 (X = Br, I) centers at high pressure further result in different degrees of emission shifts, giving rise to the gradual emergence and disappearance of EDE. This work elucidates the underlying mechanism of EDE in 0D HMHs and highlights the crucial role of halogens in determining the optical properties of metal halides.

15.
Sensors (Basel) ; 24(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38793947

RESUMEN

The rotational speed standard device that can carry loads is the key device for calibrating passive rotational speed sensors. The rotor of the passive rotational speed sensor is connected to the rotor of the standard speed device through a coupling, and the standard reference speed is provided by the standard device. Due to the rotor eccentricity, the unbalanced force of the rotor occurs, and it can not only affect the rotational speed accuracy but can also damage the mechanical bearings of the standard speed device. To solve this issue, a method for suppressing the unbalanced force of the speed standard device based on an active magnetic bearing (AMB) force compensation system is proposed. First, the overall structure of the system is briefly introduced. Then, the force feedback control system model with the AMB as the force actuator is established, and a PI controller is designed to achieve the disturbed force control. Finally, a semi-physical simulation experimental platform is built to verify the effectiveness of the proposed method. The experimental results show that the AMB force compensation system can reduce 84.4%, 81.6%, and 79.8% of the unbalanced vibration force at the frequency of 30 Hz, 90 Hz, and 150 Hz, respectively.

16.
Nano Lett ; 23(15): 7008-7013, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37466311

RESUMEN

The recent discovery of strongly correlated phases in twisted transition-metal dichalcogenides (TMDs) highlights the significant impact of twist-induced modifications on electronic structures. In this study, we employed angle-resolved photoemission spectroscopy with submicrometer spatial resolution (µ-ARPES) to investigate these modifications by comparing valence band structures of twisted (5.3°) and nontwisted (AB-stacked) bilayer regions within the same WSe2 device. Relative to the nontwisted region, the twisted area exhibits pronounced moiré bands and ∼90 meV renormalization at the Γ-valley, substantial momentum separation between different layers, and an absence of flat bands at the K-valley. We further simulated the effects of lattice relaxation, which can flatten the Γ-valley edge but not the K-valley edge. Our results provide a direct visualization of twist-induced modifications in the electronic structures of twisted TMDs and elucidate their valley-dependent responses to lattice relaxation.

17.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612670

RESUMEN

We aimed to identify serum exosomal microRNAs (miRNAs) associated with the transition from atrial fibrillation (AF) to sinus rhythm (SR) and investigate their potential as biomarkers for the early recurrence of AF within three months post-treatment. We collected blood samples from eight AF patients at Chang Gung Memorial Hospital in Taiwan both immediately before and within 14 days following rhythm control treatment. Exosomes were isolated from these samples, and small RNA sequencing was performed. Using DESeq2 analysis, we identified nine miRNAs (16-2-3p, 22-3p, 23a-3p, 23b-3p, 125a-5p, 328-3p, 423-5p, 504-5p, and 582-3p) associated with restoration to SR. Further analysis using the DIABLO model revealed a correlation between the decreased expression of miR-125a-5p and miR-328-3p and the early recurrence of AF. Furthermore, early recurrence is associated with a longer duration of AF, presumably indicating a more extensive state of underlying cardiac remodeling. In addition, the reads were mapped to mRNA sequences, leading to the identification of 14 mRNAs (AC005041.1, ARHGEF12, AMT, ANO8, BCL11A, DIO3OS, EIF4ENIF1, G2E3-AS1, HERC3, LARS, NT5E, PITX1, SLC16A12, and ZBTB21) associated with restoration to SR. Monitoring these serum exosomal miRNA and mRNA expression patterns may be beneficial for optimizing treatment outcomes in AF patients.


Asunto(s)
Fibrilación Atrial , Exosomas , MicroARNs , Humanos , Fibrilación Atrial/genética , MicroARNs/genética , Corazón , Exosomas/genética , ARN Mensajero , Anoctaminas
18.
BMC Genomics ; 24(1): 313, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37308830

RESUMEN

BACKGROUND: Rewriting the genomes of living organisms has been a long-standing aim in the biological sciences. The revelation of the CRISPR/Cas9 technology has revolutionized the entire biological field. Since its emergence, this technology has been widely applied to induce gene knockouts, insertions, deletions, and base substitutions. However, the classical version of this system was imperfect for inducing or correcting desired mutations. A subsequent development generated more advanced classes, including cytosine and adenine base editors, which can be used to achieve single nucleotide substitutions. Nevertheless, these advanced systems still suffer from several limitations, such as the inability to edit loci without a suitable PAM sequence and to induce base transversions. On the other hand, the recently emerged prime editors (PEs) can achieve all possible single nucleotide substitutions as well as targeted insertions and deletions, which show promising potential to alter and correct the genomes of various organisms. Of note, the application of PE to edit livestock genomes has not been reported yet. RESULTS: In this study, using PE, we successfully generated sheep with two agriculturally significant mutations, including the fecundity-related FecBB p.Q249R and the tail length-related TBXT p.G112W. Additionally, we applied PE to generate porcine blastocysts with a biomedically relevant point mutation (KCNJ5 p.G151R) as a porcine model of human primary aldosteronism. CONCLUSIONS: Our study demonstrates the potential of the PE system to edit the genomes of large animals for the induction of economically desired mutations and for modeling human diseases. Although prime-edited sheep and porcine blastocysts could be generated, the editing frequencies are still unsatisfactory, highlighting the need for optimizations in the PE system for efficient generation of large animals with customized traits.


Asunto(s)
Blastocisto , Mutación Puntual , Humanos , Animales , Porcinos , Ovinos , Mutación , Ganado , Nucleótidos , Canales de Potasio Rectificados Internamente Asociados a la Proteína G
19.
J Am Chem Soc ; 145(30): 16406-16416, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37432680

RESUMEN

Despite tremendous success in understanding the chemical nature and the importance of cation-π interactions in a range of biological processes, particularly in epigenetic regulation, the design and synthesis of stronger cation-π interactions in living cells remain largely elusive. Here, we design several electron-rich Trp derivatives and incorporate them into histone methylation reader domains to enhance the affinity of the reader domains for histone methylation marks via cation-π interactions in living cells. We show that this site-specific Trp replacement strategy is generally applicable for the engineering of high-affinity reader domains for the major histone H3 trimethylation marks, such as H3K4me3, H3K9me3, H3K27me3, and H3K36me3, with high specificity. Furthermore, we demonstrate that engineered reader domains can serve as powerful tools for the enrichment and imaging of histone methylation, as well as for capturing the protein interactome at chromatin marks in living cells. Therefore, our study paves the way for the design of enhanced cation-π interactions in reader proteins in living cells for various biological applications.


Asunto(s)
Epigénesis Genética , Histonas , Histonas/genética , Histonas/metabolismo , Cromatina , Metilación , Código Genético
20.
Mol Biol Evol ; 39(12)2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36382357

RESUMEN

Understanding the genetic mechanism of how animals adapt to extreme conditions is fundamental to determine the relationship between molecular evolution and changing environments. Goat is one of the first domesticated species and has evolved rapidly to adapt to diverse environments, including harsh high-altitude conditions with low temperature and poor oxygen supply but strong ultraviolet radiation. Here, we analyzed 331 genomes of domestic goats and wild caprid species living at varying altitudes (high > 3000 m above sea level and low < 1200 m), along with a reference-guided chromosome-scale assembly (contig-N50: 90.4 Mb) of a female Tibetan goat genome based on PacBio HiFi long reads, to dissect the genetic determinants underlying their adaptation to harsh conditions on the Qinghai-Tibetan Plateau (QTP). Population genomic analyses combined with genome-wide association studies (GWAS) revealed a genomic region harboring the 3'-phosphoadenosine 5'-phosphosulfate synthase 2 (PAPSS2) gene showing strong association with high-altitude adaptability (PGWAS = 3.62 × 10-25) in Tibetan goats. Transcriptomic data from 13 tissues revealed that PAPSS2 was implicated in hypoxia-related pathways in Tibetan goats. We further verified potential functional role of PAPSS2 in response to hypoxia in PAPSS2-deficient cells. Introgression analyses suggested that the PAPSS2 haplotype conferring the high-altitude adaptability in Tibetan goats originated from a recent hybridization between goats and a wild caprid species, the markhor (Capra falconeri). In conclusion, our results uncover a hitherto unknown contribution of PAPSS2 to high-altitude adaptability in Tibetan goats on QTP, following interspecific introgression and natural selection.


Asunto(s)
Estudio de Asociación del Genoma Completo , Cabras , Animales , Cabras/genética , Rayos Ultravioleta , Genómica
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