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1.
Cell ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38936359

RESUMO

Duplication is a foundation of molecular evolution and a driver of genomic and complex diseases. Here, we develop a genome editing tool named Amplification Editing (AE) that enables programmable DNA duplication with precision at chromosomal scale. AE can duplicate human genomes ranging from 20 bp to 100 Mb, a size comparable to human chromosomes. AE exhibits activity across various cell types, encompassing diploid, haploid, and primary cells. AE exhibited up to 73.0% efficiency for 1 Mb and 3.4% for 100 Mb duplications, respectively. Whole-genome sequencing and deep sequencing of the junctions of edited sequences confirm the precision of duplication. AE can create chromosomal microduplications within disease-relevant regions in embryonic stem cells, indicating its potential for generating cellular and animal models. AE is a precise and efficient tool for chromosomal engineering and DNA duplication, broadening the landscape of precision genome editing from an individual genetic locus to the chromosomal scale.

2.
Nature ; 628(8006): 99-103, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538794

RESUMO

Stable aluminosilicate zeolites with extra-large pores that are open through rings of more than 12 tetrahedra could be used to process molecules larger than those currently manageable in zeolite materials. However, until very recently1-3, they proved elusive. In analogy to the interlayer expansion of layered zeolite precursors4,5, we report a strategy that yields thermally and hydrothermally stable silicates by expansion of a one-dimensional silicate chain with an intercalated silylating agent that separates and connects the chains. As a result, zeolites with extra-large pores delimited by 20, 16 and 16 Si tetrahedra along the three crystallographic directions are obtained. The as-made interchain-expanded zeolite contains dangling Si-CH3 groups that, by calcination, connect to each other, resulting in a true, fully connected (except possible defects) three-dimensional zeolite framework with a very low density. Additionally, it features triple four-ring units not seen before in any type of zeolite. The silicate expansion-condensation approach we report may be amenable to further extra-large-pore zeolite formation. Ti can be introduced in this zeolite, leading to a catalyst that is active in liquid-phase alkene oxidations involving bulky molecules, which shows promise in the industrially relevant clean production of propylene oxide using cumene hydroperoxide as an oxidant.

3.
Nature ; 620(7973): 323-327, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37344595

RESUMO

The black phase of formamidinium lead iodide (FAPbI3) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization1-4. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI3 (refs. 5,6). Here we use in situ monitoring of the perovskite crystallization process to report an oriented nucleation mechanism that can help to avoid the presence of undesirable phases and improve the performance of photovoltaic devices in different film-processing scenarios. The resulting device has a demonstrated power-conversion efficiency of 25.4% (certified 25.0%) and the module, which has an area of 27.83 cm2, has achieved an impressive certified aperture efficiency of 21.4%.

4.
Cell ; 155(7): 1492-506, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24360273

RESUMO

Single-cell genome analyses of human oocytes are important for meiosis research and preimplantation genomic screening. However, the nonuniformity of single-cell whole-genome amplification hindered its use. Here, we demonstrate genome analyses of single human oocytes using multiple annealing and looping-based amplification cycle (MALBAC)-based sequencing technology. By sequencing the triads of the first and second polar bodies (PB1 and PB2) and the oocyte pronuclei from same female egg donors, we phase the genomes of these donors with detected SNPs and determine the crossover maps of their oocytes. Our data exhibit an expected crossover interference and indicate a weak chromatid interference. Further, the genome of the oocyte pronucleus, including information regarding aneuploidy and SNPs in disease-associated alleles, can be accurately deduced from the genomes of PB1 and PB2. The MALBAC-based preimplantation genomic screening in in vitro fertilization (IVF) enables accurate and cost-effective selection of normal fertilized eggs for embryo transfer.


Assuntos
Fertilização in vitro , Genoma Humano , Oócitos/metabolismo , Análise de Sequência de DNA/métodos , Adulto , Aneuploidia , Blastocisto/metabolismo , Feminino , Humanos , Corpos Polares/metabolismo , Polimorfismo de Nucleotídeo Único , Análise de Célula Única , Doadores de Tecidos
5.
Plant Cell ; 35(10): 3870-3888, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37338064

RESUMO

Calcium (Ca2+)-dependent protein kinases (CPKs) are essential regulators of plant responses to diverse environmental stressors, including osmotic stress. CPKs are activated by an increase in intracellular Ca2+ levels triggered by osmotic stress. However, how the levels of active CPK protein are dynamically and precisely regulated has yet to be determined. Here, we demonstrate that NaCl/mannitol-induced osmotic stress promoted the accumulation of CPK4 protein by disrupting its 26S proteasome-mediated CPK4 degradation in Arabidopsis (Arabidopsis thaliana). We isolated PLANT U-BOX44 (PUB44), a U-box type E3 ubiquitin ligase that ubiquitinates CPK4 and triggers its degradation. A calcium-free or kinase-inactive CPK4 variant was preferentially degraded compared to the Ca2+-bound active form of CPK4. Furthermore, PUB44 exhibited a CPK4-dependent negative role in the response of plants to osmotic stress. Osmotic stress induced the accumulation of CPK4 protein by inhibiting PUB44-mediated CPK4 degradation. The present findings reveal a mechanism for regulating CPK protein levels and establish the relevance of PUB44-dependent CPK4 regulation in modulating plant osmotic stress responses, providing insights into osmotic stress signal transduction mechanisms.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cálcio/metabolismo , Pressão Osmótica , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Proc Natl Acad Sci U S A ; 120(31): e2302930120, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37490538

RESUMO

This paper is concerned with the problem of reconstructing an unknown rank-one matrix with prior structural information from noisy observations. While computing the Bayes optimal estimator is intractable in general due to the requirement of computing high-dimensional integrations/summations, Approximate Message Passing (AMP) emerges as an efficient first-order method to approximate the Bayes optimal estimator. However, the theoretical underpinnings of AMP remain largely unavailable when it starts from random initialization, a scheme of critical practical utility. Focusing on a prototypical model called [Formula: see text] synchronization, we characterize the finite-sample dynamics of AMP from random initialization, uncovering its rapid global convergence. Our theory-which is nonasymptotic in nature-in this model unveils the non-necessity of a careful initialization for the success of AMP.

7.
Plant Physiol ; 195(3): 2339-2353, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38506490

RESUMO

Iron (Fe) distribution and reutilization are crucial for maintaining Fe homeostasis in plants. Here, we demonstrate that the tomato (Solanum lycopersicum) Colorless nonripening (Cnr) epimutant exhibits increased Fe retention in cell wall pectin due to an increase in pectin methylesterase (PME) activity. This ultimately leads to Fe deficiency responses even under Fe-sufficient conditions when compared to the wild type (WT). Whole-genome bisulfite sequencing revealed that modifications to cell wall-related genes, especially CG hypermethylation in the intron region of PECTIN METHYLESTERASE53 (SlPME53), are involved in the Cnr response to Fe deficiency. When this intron hypermethylation of SlPME53 was artificially induced in WT, we found that elevated SlPME53 expression was accompanied by increased PME activity and increased pectin-Fe retention. The manipulation of SlPME53, either through overexpression in WT or knockdown in Cnr, influenced levels of pectin methylesterification and accumulation of apoplast Fe in roots. Moreover, CG hypermethylation mediated by METHYLTRANSFERASE1 (SlMET1) increased SlPME53 transcript abundance, resulting in greater PME activity and higher Fe retention in cell wall pectin. Therefore, we conclude that the Cnr mutation epigenetically modulates SlPME53 expression by SlMET1-mediated CG hypermethylation, and thus the capacity of the apoplastic Fe pool, creating opportunities for genetic improvement of crop mineral nutrition.


Assuntos
Hidrolases de Éster Carboxílico , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Ferro , Raízes de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/genética , Ferro/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Metilação de DNA/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Parede Celular/metabolismo , Pectinas/metabolismo
8.
Plant Physiol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753366

RESUMO

Sclerotinia disease is one of the most devastating fungal diseases worldwide, as it reduces the yields of many economically important crops. Pathogen-secreted effectors play crucial roles in infection processes. However, key effectors of Ciboria shiraiana, the pathogen primarily responsible for sclerotinia disease in mulberry (Morus spp.), remain poorly understood. In this study, we identified and functionally characterized the effector Cs02526 in C. shiraiana and found that Cs02526 could induce cell deathin a variety of plants. Moreover, Cs02526-induced cell death was mediated by the central immune regulator BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1 (BAK1), dependent on a 67-amino acid fragment. Notably, Cs02526 homologues were widely distributed in hemibiotrophic and necrotrophic phytopathogenic fungi, but the homologues failed to induce cell death in plants. Pre-treatment of plants with recombinant Cs02526 protein enhanced resistance against both C. shiraiana and Sclerotinia sclerotiorum. Furthermore, the pathogenicity of C. shiraiana was diminished upon spraying plants with synthetic dsRNA-Cs02526. In conclusion, our findings highlight the cell death-inducing effector Cs02526 as a potential target for future biological control strategies against plant diseases.

9.
FASEB J ; 38(5): e23549, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38446465

RESUMO

Apical periodontitis (AP) is a disease caused by pathogenic microorganisms and featured with the degradation of periapical hard tissue. Our recent research showed the crucial role of Z-DNA binding protein 1 (ZBP1)-mediated necroptosis and apoptosis in the pathogenesis of AP. However, the specific regulatory mechanisms of ZBP1 in AP are not fully elucidated. It was found that metformin has a regulatory role in cell necroptosis and apoptosis. But whether and how metformin regulates necroptosis and apoptosis through the ZBP1 in the context of AP remains unknown. This study provided evidence that lipopolysaccharide (LPS) promotes the synthesis of left-handed Z-nucleic acids (Z-NA), which in turn activates ZBP1. Knockout of Zbp1 by CRISPR/Cas9 technology significantly reduced LPS-induced necroptosis and apoptosis in vitro. By using Zbp1-knockout mice, periapical bone destruction was alleviated. Moreover, type I interferon induced the expression of interferon-stimulated genes (ISGs), which serve as a major source of Z-NA. In addition, the RNA-editing enzyme Adenosine Deaminase RNA specific 1 (ADAR1) prevented the accumulation of endogenous Z-NA. Meanwhile, metformin suppressed the ZBP1-mediated necroptosis by inhibiting the expression of ZBP1 and the accumulation of ISGs. Metformin also promoted mitochondrial apoptosis, which is critical for the elimination of intracellular bacterial infection. The enhanced apoptosis further promoted the healing of infected apical bone tissues. In summary, these results demonstrated that the recognition of Z-NA by ZBP1 plays an important role in AP pathogenesis. Metformin suppressed ZBP1-mediated necroptosis and promoted apoptosis, thereby contributing to the soothing of inflammation and bone healing in AP.


Assuntos
Interferon Tipo I , Metformina , Periodontite Periapical , Camundongos , Animais , Camundongos Knockout , Lipopolissacarídeos , Morte Celular , Metformina/farmacologia , RNA , Proteínas de Ligação a RNA , Adenosina Desaminase
10.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517174

RESUMO

The influence of effort expenditure on the subjective value in feedback involving material reward has been the focus of previous research. However, little is known about the impact of effort expenditure on subjective value evaluations when feedback involves reward that is produced in the context of social interaction (e.g. self-other agreement). Moreover, how effort expenditure influences confidence (second-order subjective value) in feedback evaluations remains unclear. Using electroencephalography, this study aimed to address these questions. Event-related potentials showed that, after exerting high effort, participants exhibited increased reward positivity difference in response to self-other (dis)agreement feedback. After exerting low effort, participants reported high confidence, and the self-other disagreement feedback evoked a larger P3a. Time-frequency analysis showed that the high-effort task evoked increased frontal midline theta power. In the low (vs. high)-effort task, the frontal midline delta power for self-other disagreement feedback was enhanced. These findings suggest that, at the early feedback evaluation stage, after exerting high effort, individuals exhibit an increased sensitivity of subjective value evaluation in response to self-other agreement feedback. At the later feedback evaluation stage, after completing the low-effort task, the self-other disagreement feedback violates the individuals'high confidence and leads to a metacognitive mismatch.


Assuntos
Encéfalo , Gastos em Saúde , Humanos , Retroalimentação , Encéfalo/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Recompensa , Retroalimentação Psicológica/fisiologia
11.
Drug Resist Updat ; 76: 101117, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38996549

RESUMO

AIMS: Treatment resistance commonly emerges in small cell lung cancer (SCLC), necessitating the development of novel and effective biomarkers to dynamically assess therapeutic efficacy. This study aims to evaluate the clinical utility of aneuploid circulating tumor cells (CTCs) for risk stratification and treatment response monitoring. METHODS: A total of 126 SCLC patients (two cohorts) from two independent cancer centers were recruited as the study subjects. Blood samples were collected from these patients and aneuploid CTCs were detected. Aneuploid CTC count (ACC) and aneuploid CTC score (ACS), were used to predict progression-free survival (PFS) and overall survival (OS). The performance of the ACC and the ACS was evaluated by calculating the area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: Compared to ACC, ACS exhibited superior predictive power for PFS and OS in these 126 patients. Moreover, both univariate and multivariate analyses revealed that ACS was an independent prognostic factor. Dynamic ACS changes reflected treatment response, which is more precise than ACC changes. ACS can be used to assess chemotherapy resistance and is more sensitive than radiological examination (with a median lead time of 2.8 months; P < 0.001). When patients had high ACS levels (> 1.115) at baseline, the combination of immunotherapy and chemotherapy resulted in longer PFS (median PFS, 7.7 months; P = 0.007) and OS (median OS, 16.3 months; P = 0.033) than chemotherapy alone (median PFS, 4.9 months; median OS, 13.6 months). CONCLUSIONS: ACS could be used as a biomarker for risk stratification, treatment response monitoring, and individualized therapeutic intervention in SCLC patients.

12.
Plant J ; 113(2): 387-401, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36471650

RESUMO

Formate dehydrogenase (FDH; EC 1.2.1.2.) has been implicated in plant responses to a variety of stresses, including aluminum (Al) stress in acidic soils. However, the role of this enzyme in Al tolerance is not yet fully understood, and how FDH gene expression is regulated is unknown. Here, we report the identification and functional characterization of the tomato (Solanum lycopersicum) SlFDH gene. SlFDH encodes a mitochondria-localized FDH with Km values of 2.087 mm formate and 29.1 µm NAD+ . Al induced the expression of SlFDH in tomato root tips, but other metals did not, as determined by quantitative reverse transcriptase-polymerase chain reaction. CRISPR/Cas9-generated SlFDH knockout lines were more sensitive to Al stress and formate than wild-type plants. Formate failed to induce SlFDH expression in the tomato root apex, but NAD+ accumulated in response to Al stress. Co-expression network analysis and interaction analysis between genomic DNA and transcription factors (TFs) using PlantRegMap identified seven TFs that might regulate SlFDH expression. One of these TFs, SlSTOP1, positively regulated SlFDH expression by directly binding to its promoter, as demonstrated by a dual-luciferase reporter assay and electrophoretic mobility shift assay. The Al-induced expression of SlFDH was completely abolished in Slstop1 mutants, indicating that SlSTOP1 is a core regulator of SlFDH expression under Al stress. Taken together, our findings demonstrate that SlFDH plays a role in Al tolerance and reveal the transcriptional regulatory mechanism of SlFDH expression in response to Al stress in tomato.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , NAD/metabolismo , Alumínio/toxicidade , Alumínio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Formiatos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Plant J ; 113(6): 1146-1159, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36575579

RESUMO

Marsdenia tenacissima is a medicinal plant widely distributed in the calcium-rich karst regions of southwest China. However, the lack of a reference genome has hampered the implementation of molecular techniques in its breeding, pharmacology and domestication. We generated the chromosome-level genome assembly in Apocynaceae using combined SMRT sequencing and Hi-C. The genome length was 381.76 Mb, with 98.9% of it found on 11 chromosomes. The genome contained 222.63 Mb of repetitive sequences and 21 899 predicted gene models, with a contig N50 of 6.57 Mb. Phylogenetic analysis revealed that M. tenacissima diverged from Calotropis gigantea at least 13.43 million years ago. Comparative genomics showed that M. tenacissima underwent ancient shared whole-genome duplication. This event, together with tandem duplication, contributed to 70.71% of gene-family expansion. Both pseudogene analysis and selective pressure calculations suggested calcium-related adaptive evolution in the M. tenacissima genome. Calcium-induced differentially expressed genes (DEGs) were mainly enriched in cell-wall-related processes. Domains (e.g. Fasciclin and Amb_all) and cis-elements (e.g. MYB and MYC) frequently occurred in the coding and promoter regions of cell-wall DEGs, respectively, and the expression levels of these genes correlated significantly with those of calcium-signal-related transcription factors. Moreover, calcium addition increased tenacissoside I, G and H contents. The availability of this high-quality genome provides valuable genomic information for genetic breeding and molecular design, and lends insights into the calcium adaptation of M. tenacissima in karst areas.


Assuntos
Marsdenia , Plantas Medicinais , Cálcio , Marsdenia/genética , Filogenia , Melhoramento Vegetal
14.
Immunology ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804253

RESUMO

Retinopathy of prematurity (ROP) is a retinal disease-causing retinal neovascularization that can lead to blindness. Oxygen-induced retinopathy (OIR) is a widely used ROP animal model. Icariin (ICA) has anti-oxidative and anti-inflammation properties; however, whether ICA has a regulatory effect on OIR remains unclear. In this study, ICA alleviated pathological neovascularization, microglial activation and blood-retina barrier (BRB) damage in vivo. Further results indicated that endothelial cell tube formation, migration and proliferation were restored by ICA treatment in vitro. Proteomic microarrays and molecular mimicry revealed that ICA can directly bind to hexokinase 2 (HK2) and decrease HK2 protein expression in vivo and in vitro. In addition, ICA inhibited the AKT/mTOR/HIF1α pathway activation. The effects of ICA on pathological neovascularization, microglial activation and BRB damage disappeared after HK2 overexpression in vivo. Similarly, the endothelial cell function was revised after HK2 overexpression. HK2 overexpression reversed ICA-induced AKT/mTOR/HIF1α pathway inhibition in vivo and in vitro. Therefore, ICA prevented pathological angiogenesis in OIR in an HK2-dependent manner, implicating ICA as a potential therapeutic agent for ROP.

15.
J Hepatol ; 80(3): 443-453, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38086446

RESUMO

BACKGROUND & AIMS: The liver is a common site of cancer metastasis, most commonly from colorectal cancer, and primary liver cancers that have metastasized are associated with poor outcomes. The underlying mechanisms by which the liver defends against these processes are largely unknown. Prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) are highly expressed in the liver. They positively regulate each other and their deletion results in primary liver cancer. Here we investigated their roles in primary and secondary liver cancer metastasis. METHODS: We identified common target genes of PHB1 and MAT1A using a metastasis array, and measured promoter activity and transcription factor binding using luciferase reporter assays and chromatin immunoprecipitation, respectively. We examined how PHB1 or MAT1A loss promotes liver cancer metastasis and whether their loss sensitizes to colorectal liver metastasis (CRLM). RESULTS: Matrix metalloproteinase-7 (MMP-7) is a common target of MAT1A and PHB1 and its induction is responsible for increased migration and invasion when MAT1A or PHB1 is silenced. Mechanistically, PHB1 and MAT1A negatively regulate MMP7 promoter activity via an AP-1 site by repressing the MAFG-FOSB complex. Loss of MAT1A or PHB1 also increased MMP-7 in extracellular vesicles, which were internalized by colon and pancreatic cancer cells to enhance their oncogenicity. Low hepatic MAT1A or PHB1 expression sensitized to CRLM, but not if endogenous hepatic MMP-7 was knocked down first, which lowered CD4+ T cells while increasing CD8+ T cells in the tumor microenvironment. Hepatocytes co-cultured with colorectal cancer cells express less MAT1A/PHB1 but more MMP-7. Consistently, CRLM raised distant hepatocytes' MMP-7 expression in mice and humans. CONCLUSION: We have identified a PHB1/MAT1A-MAFG/FOSB-MMP-7 axis that controls primary liver cancer metastasis and sensitization to CRLM. IMPACT AND IMPLICATIONS: Primary and secondary liver cancer metastasis is associated with poor outcomes but whether the liver has underlying defense mechanism(s) against metastasis is unknown. Here we examined the hypothesis that hepatic prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) cooperate to defend the liver against metastasis. Our studies found PHB1 and MAT1A form a complex that suppresses matrix metalloproteinase-7 (MMP-7) at the transcriptional level and loss of either PHB1 or MAT1A sensitizes the liver to metastasis via MMP-7 induction. Strategies that target the PHB1/MAT1A-MMP-7 axis may be a promising approach for the treatment of primary and secondary liver cancer metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Colorretais/genética , Neoplasias Hepáticas/patologia , Metaloproteinase 7 da Matriz/genética , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Proibitinas , Microambiente Tumoral
16.
J Cell Sci ; 135(7)2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35260907

RESUMO

Cardiomyocyte elongation and alignment, a critical step in cardiomyocyte maturation starting from the perinatal stage, is crucial for formation of the highly organized intra- and inter-cellular structures for spatially and temporally ordered contraction in adult cardiomyocytes. However, the mechanism(s) underlying the control of cardiomyocyte alignment remains elusive. Here, we report that SIRT1, the most conserved NAD+-dependent protein deacetylase highly expressed in perinatal heart, plays an important role in regulating cardiomyocyte remodeling during development. We observed that SIRT1 deficiency impairs the alignment of cardiomyocytes/myofibrils and disrupts normal beating patterns at late developmental stages in an in vitro differentiation system from human embryonic stem cells. Consistently, deletion of SIRT1 at a late developmental stage in mouse embryos induced the irregular distribution of cardiomyocytes and misalignment of myofibrils, and reduced the heart size. Mechanistically, the expression of several genes involved in chemotaxis, including those in the CXCL12/CXCR4 and CCL2/CCR2/CCR4 pathways, was dramatically blunted during maturation of SIRT1-deficient cardiomyocytes. Pharmacological inhibition of CCL2 signaling suppressed cardiomyocyte alignment. Our study identifies a regulatory factor that modulates cardiomyocyte alignment at the inter-cellular level during maturation.


Assuntos
Células-Tronco Embrionárias Humanas , Miócitos Cardíacos , Sirtuína 1 , Animais , Diferenciação Celular , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo
17.
Hum Brain Mapp ; 45(2): e26611, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339957

RESUMO

Advisors generally evaluate advisee-relevant feedback after advice giving. The response to these feedback-(1) whether the advice is accepted and (2) whether the advice is optimal-usually involves prestige. Prior literature has found that prestige is the basis by which individuals attain a superior status in the social hierarchy. However, whether advisors are motivated to attain a superior status when engaging in advice giving remains uncharacterized. Using event-related potentials, this study investigates how advisors evaluate feedback after giving advice to superior (vs. inferior) status advisees. A social hierarchy was first established based on two advisees (one was ranked as superior status and another as inferior status) as well as participants' performance in a dot-estimation task in which all participants were ranked as medium status. Participants then engaged in a game in which they were assigned roles as advisors to a superior or inferior status advisee. Afterward, the participants received feedback in two phases. In Phase 1, participants were told whether the advisees accepted the advice provided. In Phase 2, the participants were informed whether the advice they provided was correct. In these two phases, when the advisee was of superior status, participants exhibited stronger feedback-related negativity and P300 difference in response to (1) whether their advice was accepted, and (2) whether their advice was correct. Moreover, the P300 was notably larger when the participants' correct advice led to a gain for a superior-status advisee. In the context of advice giving, advisors are particularly motivated to attain a superior status when the feedback involving social hierarchies, which is reflected in higher sensitivity to feedback associated with superior status advisees at earlier and later stages during feedback evaluations in brains.


Assuntos
Potenciais Evocados , Hierarquia Social , Humanos , Retroalimentação , Potenciais Evocados/fisiologia , Encéfalo/fisiologia , Retroalimentação Psicológica/fisiologia , Eletroencefalografia
18.
BMC Plant Biol ; 24(1): 170, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443797

RESUMO

BACKGROUND: Panax notoginseng (Burk) F. H. Chen is one of the most famous Chinese traditional medicinal plants. The taproot is the main organ producing triterpenoid saponins, and its development is directly linked to the quality and yield of the harvested P. notoginseng. However, the mechanisms underlying the dynamic metabolic changes occurring during taproot development of P. notoginseng are unknown. RESULTS: We carried out metabolomic and transcriptomic analyses to investigate metabolites and gene expression during the development of P. notoginseng taproots. The differentially accumulated metabolites included amino acids and derivatives, nucleotides and derivatives, and lipids in 1-year-old taproots, flavonoids and terpenoids in 2- and 3-year-old taproots, and phenolic acids in 3-year-old taproots. The differentially expressed genes (DEGs) are related to phenylpropanoid biosynthesis, metabolic pathway and biosynthesis of secondary metabolites at all three developmental stages. Integrative analysis revealed that the phenylpropanoid biosynthesis pathway was involved in not only the development of but also metabolic changes in P. notoginseng taproots. Moreover, significant accumulation of triterpenoid saponins in 2- and 3-year-old taproots was highly correlated with the up-regulated expression of cytochrome P450s and uridine diphosphate-dependent glycosyltransferases genes. Additionally, a gene encoding RNase-like major storage protein was identified to play a dual role in the development of P. notoginseng taproots and their triterpenoid saponins synthesis. CONCLUSIONS: These results elucidate the molecular mechanism underlying the accumulation of and change relationship between primary and secondary metabolites in P. notoginseng taproots, and provide a basis for the quality control and genetic improvement of P. notoginseng.


Assuntos
Panax notoginseng , Saponinas , Triterpenos , Panax notoginseng/genética , Metaboloma , Perfilação da Expressão Gênica
19.
Artigo em Inglês | MEDLINE | ID: mdl-39042281

RESUMO

Self-deception refers to an individual holding inflated beliefs about their abilities, and it plays a crucial role in human behavior and decision-making. The present study employed event-related potentials (ERPs) technique to explore the neural responses to the impacts of social comparison direction and comparison gap on self-deceptive behavior. They were instructed to predict their performance in the forward-looking paradigm. Behavioral responses and neural reactions during the decision-making process were documented. The behavioral results indicated that, in contrast to the downward comparison condition, participants engaged in upward comparison exhibited more occurrences of self-deception. However, within the context of upward comparison, participants demonstrated a higher frequency of self-deception in the large gap condition compared with the small gap condition. The ERP results showed that induced self-deception under conditions with a large comparative gap between participants and their paired counterparts stimulated larger P300 and smaller N400 amplitude than under conditions with a small gap. However, when participants were in the upward comparison situation, the late positive potential (LPP) amplitude induced by self-deception behavior in the condition of a large comparison gap between participants and paired opponents was larger than that in the condition of a small comparison gap. These results indicated that individuals in the large gap group feel strong unfairness and negative emotions. More importantly, the self-deception induced by the large gap group in the upward comparison situation used fewer cognitive resources than the small gap condition, whereas the individuals in the downward comparison situation did not show the difference in cognitive resources.

20.
Small ; : e2402049, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554015

RESUMO

Supercapacitors demonstrate promising potential for flexible, multi-functional energy storage devices; however, their widespread adoption is confronted by fabrication challenges. To access a combination of desirable device qualities such as flexibility, lightweight, structural stability, and enhanced electrochemical performance, carbon fiber (CF) can be utilized as a current collector, alongside graphene as an electrochemically active material. Yet achieving a cost-effective, large-scale graphene production, particularly on CF, remains challenging. Here, a rapid (<1 min) photothermal approach is developed for the large-scale production of graphene directly onto CF, utilizing polyaniline (PANI) as a polymer precursor. The in situ electropolymerization of PANI on CF facilitates its rapid synthesis on large areas, followed by conversion into graphene networks, enabling the binder-free fabrication of supercapacitor devices. These devices exhibit an areal capacitance of 180 mF cm-2 (at 2 mA cm-2 in 1 m H2SO4), an order of magnitude higher than other fabric-based devices. Moreover, the devised photothermal strategy allows for one-step preparation of supercapacitor devices on areas exceeding 100 cm-2, yielding an absolute areal capacitance of 4.5 F. The proportional increase in capacitance with device area facilitates scaling and indicates the commercial viability of this approach for low-cost, energy-efficient, and high-throughput production of lightweight, high-performance graphene-based multi-functional supercapacitor devices.

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