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1.
Cell ; 184(5): 1156-1170.e14, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33539781

RESUMO

Cultivated rice varieties are all diploid, and polyploidization of rice has long been desired because of its advantages in genome buffering, vigorousness, and environmental robustness. However, a workable route remains elusive. Here, we describe a practical strategy, namely de novo domestication of wild allotetraploid rice. By screening allotetraploid wild rice inventory, we identified one genotype of Oryza alta (CCDD), polyploid rice 1 (PPR1), and established two important resources for its de novo domestication: (1) an efficient tissue culture, transformation, and genome editing system and (2) a high-quality genome assembly discriminated into two subgenomes of 12 chromosomes apiece. With these resources, we show that six agronomically important traits could be rapidly improved by editing O. alta homologs of the genes controlling these traits in diploid rice. Our results demonstrate the possibility that de novo domesticated allotetraploid rice can be developed into a new staple cereal to strengthen world food security.


Assuntos
Produtos Agrícolas/genética , Domesticação , Oryza/genética , Sistemas CRISPR-Cas , Segurança Alimentar , Edição de Genes , Variação Genética , Genoma de Planta , Oryza/classificação , Poliploidia
2.
Cell ; 172(1-2): 249-261.e12, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29328914

RESUMO

Humans heavily rely on dozens of domesticated plant species that have been further improved through intensive breeding. To evaluate how breeding changed the tomato fruit metabolome, we have generated and analyzed a dataset encompassing genomes, transcriptomes, and metabolomes from hundreds of tomato genotypes. The combined results illustrate how breeding globally altered fruit metabolite content. Selection for alleles of genes associated with larger fruits altered metabolite profiles as a consequence of linkage with nearby genes. Selection of five major loci reduced the accumulation of anti-nutritional steroidal glycoalkaloids in ripened fruits, rendering the fruit more edible. Breeding for pink tomatoes modified the content of over 100 metabolites. The introgression of resistance genes from wild relatives in cultivars also resulted in major and unexpected metabolic changes. The study reveals a multi-omics view of the metabolic breeding history of tomato, as well as provides insights into metabolome-assisted breeding and plant biology.


Assuntos
Frutas/genética , Metaboloma , Metabolômica/métodos , Melhoramento Vegetal/métodos , Solanum lycopersicum/genética , Flavonoides/genética , Flavonoides/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Seleção Artificial
3.
Nature ; 606(7914): 527-534, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35676474

RESUMO

Missing heritability in genome-wide association studies defines a major problem in genetic analyses of complex biological traits1,2. The solution to this problem is to identify all causal genetic variants and to measure their individual contributions3,4. Here we report a graph pangenome of tomato constructed by precisely cataloguing more than 19 million variants from 838 genomes, including 32 new reference-level genome assemblies. This graph pangenome was used for genome-wide association study analyses and heritability estimation of 20,323 gene-expression and metabolite traits. The average estimated trait heritability is 0.41 compared with 0.33 when using the single linear reference genome. This 24% increase in estimated heritability is largely due to resolving incomplete linkage disequilibrium through the inclusion of additional causal structural variants identified using the graph pangenome. Moreover, by resolving allelic and locus heterogeneity, structural variants improve the power to identify genetic factors underlying agronomically important traits leading to, for example, the identification of two new genes potentially contributing to soluble solid content. The newly identified structural variants will facilitate genetic improvement of tomato through both marker-assisted selection and genomic selection. Our study advances the understanding of the heritability of complex traits and demonstrates the power of the graph pangenome in crop breeding.


Assuntos
Variação Genética , Genoma de Planta , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Solanum lycopersicum , Alelos , Produtos Agrícolas/genética , Genoma de Planta/genética , Desequilíbrio de Ligação , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo
4.
Proc Natl Acad Sci U S A ; 121(5): e2313656121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252822

RESUMO

Long non-coding RNA (lncRNA) serves as a vital regulator of bone metabolism, but its role in pathologically overactive osteoclast differentiation remains elusive. Here, we identify lncRNA Dancr (Differentiation Antagonizing Non-protein Coding RNA) as a critical suppressor of osteoclastogenesis and bone resorption, which is down-regulated in response to estrogen deficiency. Global or osteoclast-specific Dancr Knockout mice display significant trabecular bone deterioration and enhanced osteoclast activity, but minimal alteration of bone formation. Moreover, the bone-targeted delivery of Dancr by Adeno-associated viral remarkably attenuates ovariectomy-induced osteopenia in mice. Mechanistically, Dancr establishes a direct interaction with Brahma-related gene 1 to prevent its binding and preserve H3K27me3 enrichment at the nuclear factor of activated T cells 1 and proliferator-activated receptor gamma coactivator 1-beta promoters, thereby maintaining appropriate expression of osteoclastic genes and metabolic programs during osteoclastogenesis. These results demonstrate that Dancr is a key molecule maintaining proper osteoclast differentiation and bone homeostasis under physiological conditions, and Dancr overexpression constitutes a potential strategy for treating osteoporosis.


Assuntos
Fatores de Transcrição NFATC , Osteogênese , RNA Longo não Codificante , Fatores de Transcrição , Animais , Feminino , Camundongos , Homeostase , Camundongos Knockout , Fatores de Transcrição NFATC/genética , Osteoclastos , Osteogênese/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética
5.
Nature ; 583(7815): 277-281, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32528176

RESUMO

Plant hormones known as strigolactones control plant development and interactions between host plants and symbiotic fungi or parasitic weeds1-4. In Arabidopsis thaliana and rice, the proteins DWARF14 (D14), MORE AXILLARY GROWTH 2 (MAX2), SUPPRESSOR OF MAX2-LIKE 6, 7 and 8 (SMXL6, SMXL7 and SMXL8) and their orthologues form a complex upon strigolactone perception and play a central part in strigolactone signalling5-10. However, whether and how strigolactones activate downstream transcription remains largely unknown. Here we use a synthetic strigolactone to identify 401 strigolactone-responsive genes in Arabidopsis, and show that these plant hormones regulate shoot branching, leaf shape and anthocyanin accumulation mainly through transcriptional activation of the BRANCHED 1, TCP DOMAIN PROTEIN 1 and PRODUCTION OF ANTHOCYANIN PIGMENT 1 genes. We find that SMXL6 targets 729 genes in the Arabidopsis genome and represses the transcription of SMXL6, SMXL7 and SMXL8 by binding directly to their promoters, showing that SMXL6 serves as an autoregulated transcription factor to maintain the homeostasis of strigolactone signalling. These findings reveal an unanticipated mechanism through which a transcriptional repressor of hormone signalling can directly recognize DNA and regulate transcription in higher plants.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais/genética , Transcrição Gênica , Antocianinas/biossíntese , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Genes de Plantas/genética , Reguladores de Crescimento de Plantas/biossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Mol Cell ; 70(5): 825-841.e6, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29861161

RESUMO

Super-enhancers are large clusters of enhancers that activate gene expression. Broad trimethyl histone H3 lysine 4 (H3K4me3) often defines active tumor suppressor genes. However, how these epigenomic signatures are regulated for tumor suppression is little understood. Here we show that brain-specific knockout of the H3K4 methyltransferase MLL4 (a COMPASS-like enzyme, also known as KMT2D) in mice spontaneously induces medulloblastoma. Mll4 loss upregulates oncogenic Ras and Notch pathways while downregulating neuronal gene expression programs. MLL4 enhances DNMT3A-catalyzed DNA methylation and SIRT1/BCL6-mediated H4K16 deacetylation, which antagonize expression of Ras activators and Notch pathway components, respectively. Notably, Mll4 loss downregulates tumor suppressor genes (e.g., Dnmt3a and Bcl6) by diminishing broad H3K4me3 and super-enhancers and also causes widespread impairment of these epigenomic signatures during medulloblastoma genesis. These findings suggest an anti-tumor role for super-enhancers and provide a unique tumor-suppressive mechanism in which MLL4 is necessary to maintain broad H3K4me3 and super-enhancers at tumor suppressor genes.


Assuntos
Neoplasias Cerebelares/genética , Metilação de DNA , Genes Supressores de Tumor , Histona-Lisina N-Metiltransferase/genética , Meduloblastoma/genética , Oncogenes , Processamento de Proteína Pós-Traducional , Acetilação , Animais , Proliferação de Células , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Regulação Neoplásica da Expressão Gênica , Genes ras , Histona-Lisina N-Metiltransferase/deficiência , Lisina , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo
7.
Plant J ; 118(6): 1872-1888, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38481350

RESUMO

As a plant-specific transcription factor, lateral organ boundaries domain (LBD) protein was reported to regulate plant growth and stress response, but the functional research of subfamily II genes is limited. SlMYC2, a master regulator of Jasmonic acid response, has been found to exhibit high expression levels in fruit and has been implicated in the regulation of fruit ripening and resistance to Botrytis. However, its role in fruit expansion remains unknown. In this study, we present evidence that a subfamily II member of LBD, namely SlLBD40, collaborates with SlMYC2 in the regulation of fruit expansion. Overexpression of SlLBD40 significantly promoted fruit growth by promoting mesocarp cell expansion, while knockout of SlLBD40 showed the opposite result. Similarly, SlMYC2 knockout resulted in a significant decrease in cell expansion within the fruit. Genetic analysis indicated that SlLBD40-mediated cell expansion depends on the expression of SlMYC2. SlLBD40 bound to the promoter of SlEXPA5, an expansin gene, but did not activate its expression directly. While, the co-expression of SlMYC2 and SlLBD40 significantly stimulated the activation of SlEXPA5, leading to an increase in fruit size. SlLBD40 interacted with SlMYC2 and enhanced the stability and abundance of SlMYC2. Furthermore, SlMYC2 directly targeted and activated the expression of SlLBD40, which is essential for SlLBD40-mediated fruit expansion. In summary, our research elucidates the role of the interaction between SlLBD40 and SlMYC2 in promoting cell expansion in tomato fruits, thus providing novel insights into the molecular genetics underlying fruit growth.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Solanum lycopersicum , Fatores de Transcrição , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética
8.
Am J Pathol ; 194(1): 52-70, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37820926

RESUMO

Loss of hepatocyte nuclear factor 4α (HNF4α) expression is frequently observed in end-stage liver disease and associated with loss of vital liver functions, thus increasing mortality. Loss of HNF4α expression is mediated by inflammatory cytokines, such as transforming growth factor (TGF)-ß. However, details of how HNF4α is suppressed are largely unknown to date. Herein, TGF-ß did not directly inhibit HNF4α but contributed to its transcriptional regulation by SMAD2/3 recruiting acetyltransferase CREB-binding protein/p300 to the HNF4α promoter. The recruitment of CREB-binding protein/p300 is indispensable for CCAAT/enhancer-binding protein α (C/EBPα) binding, another essential requirement for constitutive HNF4α expression in hepatocytes. Consistent with the in vitro observation, 67 of 98 patients with hepatic HNF4α expressed both phospho-SMAD2 and C/EBPα, whereas 22 patients without HNF4α expression lacked either phospho-SMAD2 or C/EBPα. In contrast to the observed induction of HNF4α, SMAD2/3 inhibited C/EBPα transcription. Long-term TGF-ß incubation resulted in C/EBPα depletion, which abrogated HNF4α expression. Intriguingly, SMAD2/3 inhibitory binding to the C/EBPα promoter was abolished by insulin. Two-thirds of patients without C/EBPα lacked membrane glucose transporter type 2 expression in hepatocytes, indicating insulin resistance. Taken together, these data indicate that hepatic insulin sensitivity is essential for hepatic HNF4α expression in the condition of inflammation.


Assuntos
Proteína de Ligação a CREB , Insulina , Humanos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína de Ligação a CREB/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta/metabolismo
9.
Plant Physiol ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687888

RESUMO

Over the past 10,000 years, tomato species have undergone both unintentional and intentional selection to enhance their favorable traits for human consumption and manufacturing. These selection processes have significantly influenced the genomes of tomato species and have played a critical role in improving tomato varieties. In this review, we summarize recent advances in tomato genome sequencing, explore the impact of human-driven selection, and recapitulate key genes associated with important agronomic traits in tomato breeding. We provide several examples of genomics-guided tomato breeding to highlight the potential of genome resources in facilitating tomato improvement. Furthermore, we elaborate the progress and strategies of tomato breeding through genomic designing, and present how such efforts can help future enhancements of tomato to align with the demands of sustainability and evolving human societies.

10.
J Physiol ; 602(6): 1175-1197, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38431908

RESUMO

Non-invasive transcranial direct-current stimulation (tDCS) is a safe ischaemic stroke therapy. Cathodal bilateral tDCS (BtDCS) is a modified tDCS approach established by us recently. Because selenium (Se) plays a crucial role in cerebral ischaemic injury, we investigated whether cathodal BtDCS conferred neuroprotection via regulating Se-dependent signalling in rat cerebral ischaemia-reperfusion (I/R) injury. We first showed that the levels of Se and its transport protein selenoprotein P (SEPP1) were reduced in the rat cortical penumbra following I/R, whereas cathodal BtDCS prevented the reduction of Se and SEPP1. Interestingly, direct-current stimulation (DCS) increased SEPP1 level in cultured astrocytes subjected to oxygen-glucose deprivation reoxygenation (OGD/R) but had no effect on SEPP1 level in OGD/R-insulted neurons, indicating that DCS may increase Se in ischaemic neurons by enhancing the synthesis and secretion of SEPP1 in astrocytes. We then revealed that DCS reduced the number of injured mitochondria in OGD/R-insulted neurons cocultured with astrocytes. DCS and BtDCS prevented the reduction of the mitochondrial quality-control signalling, vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4), in OGD/R-insulted neurons cocultured with astrocytes and the ischaemic brain respectively. Under the same experimental conditions, downregulation of SEPP1 blocked DCS- and BtDCS-induced upregulation of VAMP2 and STX4. Finally, we demonstrated that cathodal BtDCS increased Se to reduce infract volume following I/R. Together, the present study uncovered a molecular mechanism by which cathodal BtDCS confers neuroprotection through increasing SEPP1 in astrocytes and subsequent upregulation of SEPP1/VAMP2/STX4 signalling in ischaemic neurons after rat cerebral I/R injury. KEY POINTS: Cathodal bilateral transcranial direct-current stimulation (BtDCS) prevents the reduction of selenium (Se) and selenoprotein P in the ischaemic penumbra. Se plays a crucial role in cerebral ischaemia injury. Direct-current stimulation reduces mitochondria injury and blocks the reduction of vesicle-associated membrane protein 2 (VAMP2) and syntaxin-4 (STX4) in oxygen-glucose deprivation reoxygenation-insulted neurons following coculturing with astrocytes. Cathodal BtDCS regulates Se/VAMP2/STX4 signalling to confer neuroprotection after ischaemia.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Selênio , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Ratos , Animais , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Neuroproteção/fisiologia , Proteína 2 Associada à Membrana da Vesícula , Selenoproteína P , Oxigênio/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Glucose/metabolismo , Proteínas Qa-SNARE
11.
J Am Chem Soc ; 146(11): 7324-7331, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38445458

RESUMO

The discovery of superconductivity in twisted bilayer graphene has reignited enthusiasm in the field of flat-band superconductivity. However, important challenges remain, such as constructing a flat-band structure and inducing a superconducting state in materials. Here, we successfully achieved superconductivity in Bi2O2Se by pressure-tuning the flat-band electronic structure. Experimental measurements combined with theoretical calculations reveal that the occurrence of pressure-induced superconductivity at 30 GPa is associated with a flat-band electronic structure near the Fermi level. Moreover, in Bi2O2Se, a van Hove singularity is observed at the Fermi level alongside pronounced Fermi surface nesting. These remarkable features play a crucial role in promoting strong electron-phonon interactions, thus potentially enhancing the superconducting properties of the material. These findings demonstrate that pressure offers a potential experimental strategy for precisely tuning the flat band and achieving superconductivity.

12.
Emerg Infect Dis ; 30(7): 1420-1424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38916588

RESUMO

To evaluate the risk of acquiring syphilis from a donated kidney, we evaluated kidney transplantation pairs from West China Hospital, Sichuan, China, during 2007-2022. Donor-derived syphilis was rare. Risk may be higher if donors have active syphilis and may be reduced if recipients receive ceftriaxone.


Assuntos
Transplante de Rim , Sífilis , Doadores de Tecidos , Humanos , Transplante de Rim/efeitos adversos , Sífilis/epidemiologia , China/epidemiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Fatores de Risco
13.
Anal Chem ; 96(1): 325-330, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38154143

RESUMO

The mechanism of selenium in the UV photochemical vapor generation (PVG) process was investigated by the use of multiple analytical methods. It was found that the UV-induced photooxidation trapping of the generated volatile SeH2 should be responsible for the previous opinion of relative inertness of Se(VI) in PVG with formic acid. Furthermore, the formation of Se(IV) was found during the PVG process, and the comproportionation of Se(IV) with SeH2 and the photooxidation of Se(IV) into Se(VI) were investigated. Then, a preliminary model was proposed for the PVG process of Se(VI) and Se(IV) with low-molecular-weight organic acids. Then, a novel, simple, and green photocontrolled method without any photocatalyst was thus proposed for the nonchromatographic speciation analysis of Se(IV) and Se(VI), with a limit of detection of 0.2 and 5 ng/mL, respectively.

14.
Int J Exp Pathol ; 105(2): 64-74, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38328944

RESUMO

Transforming growth factor (TGF)-ß and toll-like receptors (TLRs) have been shown to independently modulate the proliferation of hepatocellular carcinoma (HCC). Since a direct cross-talk between these two signalling pathways in HCC has not been clearly described before, we aimed here to explore the possibility of such interaction. A human HCC tissue array (n = 20 vs. four control samples), human HCC samples (n = 10) and steatohepatitis-driven murine HCC samples (control, NASH and HCC; n = 6/group) were immunostained for TGFßR1, pSMAD2, TRAF6, IRAK1 and PCNA. The results were confirmed by immunoblotting. Effects of constant activation of the SMAD pathway by constitutive expression of ALK5 or knockdown of mediators of TLR signalling, IRAK1 and MyD88, on HCC proliferation, were investigated in the HCC cell line (HUH-7) after treatment with TGFß1 cytokine or TGFßR1 kinase inhibitor (LY2157299) using PCNA and MTS assay. TGFßR1 expression is decreased in human and murine HCC and associated with downregulated pSMAD2, but increased IRAK1, TRAF6 and PCNA staining. TGFßR1 kinase inhibition abolished the cytostatic effects of TGFß1 and led to the induction of IRAK1, pIRAK1 and elevated mRNA levels of TLR-9. Overexpression of ALK5 and knockdown of MyD88 or IRAK1 augmented the cytostatic effects of TGFß1 on HUH-7. In another epithelial HCC cell line, that is, HepG2, TGFßR1 kinase inhibitor similarly elevated cellular proliferation. There is a balance between the canonical SMAD-driven tumour-suppressing arm and the non-canonical tumour-promoting arm of TGFß signalling. Disruption of this balance, by inhibition of the canonical pathway, induces HCC proliferation through TLR signalling.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Citostáticos , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/patologia , Proliferação de Células , Neoplasias Hepáticas/patologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
Opt Express ; 32(3): 4189-4200, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297625

RESUMO

Plasmonic direct-write lithography (PDWL) provides a potential tool for the fabrication and manufacturing at the nano scale due to its high-resolution and low-cost. However, the shallow exposure depth hinders its practical application. Here, we incorporate the plasmonic slab lenses (PSLs) into PDWL to amplify and compensate evanescent waves, leading to improved light intensity, depth, resolution and better tolerance to the air gap beyond the near field optical lithography. Two typical plasmonic probes with different nanostructure and localized plasmonic resonance mechanisms are designed and fabricated as representatives, the local intensity enhancement of which mainly depend on the oscillations of transverse and longitudinal electric field components, respectively. Optimizations considering the PSL structure, material and the illuminating wavelength are performed to amplify different field components and figure out the best lithography configuration. Simulation results indicate that Ag-Ag cavity PSL and 355 nm illumination is the best combination for the lithography with bowknot aperture probe, while the semi-ring probe exhibits better performance under the condition of Ag-Al cavity PSL and 405 nm illumination. The semi-ring probe in combination with a plasmonic cavity, for instance, is demonstrated to enhance the light intensity by 4 times at the bottom layer of the photoresist compared to that without PSL and realize a lithography resolution of 23 nm. Our scheme is believed to boost the application of PDWL as a high-resolution and low-cost nanofabrication technology, and it may even serve as an alternative for the high-cost scanning method, such as focused ion beam and electron beam lithography.

16.
Plant Cell ; 33(2): 306-321, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33793793

RESUMO

Unisexual flowers provide a useful system for studying plant sex determination. In cucumber (Cucumis sativus L.), three major Mendelian loci control unisexual flower development, Female (F), androecious [a; 1-aminocyclopropane-1-carboxylate {ACC} synthase 11, acs11], and Monoecious (M; ACS2), referred to here as the Female, Androecious, Monoecious (FAM) model, in combination with two genes, gynoecious (g, the WIP family C2H2 zinc finger transcription factor gene WIP1) and the ethylene biosynthetic gene ACC oxidase 2 (ACO2). The F locus, conferring gynoecy and the potential for increasing fruit yield, is defined by a 30.2-kb tandem duplication containing three genes. However, the gene that determines the Female phenotype, and its mechanism, remains unknown. Here, we created a set of mutants and revealed that ACS1G is responsible for gynoecy conferred by the F locus. The duplication resulted in ACS1G acquiring a new promoter and expression pattern; in plants carrying the F locus duplication, ACS1G is expressed early in floral bud development, where it functions with ACO2 to generate an ethylene burst. The resulting ethylene represses WIP1 and activates ACS2 to initiate gynoecy. This early ACS1G expression bypasses the need for ACS11 to produce ethylene, thereby establishing a dominant pathway for female floral development. Based on these findings, we propose a model for how these ethylene biosynthesis genes cooperate to control unisexual flower development in cucumber.


Assuntos
Cucumis sativus/enzimologia , Cucumis sativus/genética , Flores/enzimologia , Flores/genética , Liases/genética , Sequência de Aminoácidos , Regulação da Expressão Gênica de Plantas , Loci Gênicos , Genoma de Planta , Genótipo , Glucuronidase/metabolismo , Liases/química , Fenótipo , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Langmuir ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38981093

RESUMO

We present our studies on the adsorption, deprotonation, and reactions of 4,4″-diethynyl-1,1':4',1″-terphenyl on Cu(111) under ultrahigh-vacuum conditions using scanning tunneling microscopy combined with density functional theory calculations. Sequential annealing treatments induce deprotonation of pristine molecules followed by chemical reactions, resulting in branched nanostructures. Within the nanostructures, a previously unreported, double-spot linkage is observed. Our density functional theory calculations unravel that this linkage corresponds to a five-membered copper metallacycle.

18.
Cereb Cortex ; 33(21): 10918-10930, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37718244

RESUMO

The comprehension of metaphor, a vivid and figurative language, is a complex endeavor requiring cooperation among multiple cognitive systems. There are still many important questions regarding neural mechanisms implicated in specific types of metaphor. To address these questions, we conducted activation likelihood estimation meta-analyses on 30 studies (containing data of 480 participants) and meta-analytic connectivity modeling analyses. First, the results showed that metaphor comprehension engaged the inferior frontal gyrus, middle temporal gyrus, fusiform gyrus, lingual gyrus, and middle occipital gyrus-all in the left hemisphere. In addition to the commonly reported networks of language and attention, metaphor comprehension engaged networks of visual. Second, sub-analysis showed that the contextual complexity can modulate figurativeness, with the convergence on the left fusiform gyrus during metaphor comprehension at discourse-level. Especially, right hemisphere only showed convergence in studies of novel metaphors, suggesting that the right hemisphere is more associated with difficulty than metaphorical. The work here extends knowledge of the neural mechanisms underlying metaphor comprehension in individual brain regions and neural networks.


Assuntos
Compreensão , Metáfora , Humanos , Compreensão/fisiologia , Lateralidade Funcional/fisiologia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Redes Neurais de Computação
19.
J Nanobiotechnology ; 22(1): 2, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38169390

RESUMO

BACKGROUND: Off-targeted distribution of chemotherapeutic drugs causes severe side effects, further leading to poor prognosis and patient compliance. Ligand/receptor-mediated targeted drug delivery can improve drug accumulation in the tumor but it always attenuated by protein corona barriers. RESULTS: To address these problems, a radically different strategy is proposed that can leave the off-targeted drugs inactive but activate the tumor-distributed drugs for cancer-targeting therapy in a tumor microenvironment-independent manner. The feasibility and effectiveness of this strategy is demonstrated by developing an ultrasound (US)-activated prodrug-loaded liposome (CPBSN38L) comprising the sonosensitizer chlorin e6 (Ce6)-modified lipids and the prodrug of pinacol boronic ester-conjugated SN38 (PBSN38). Once CPBSN38L is accumulated in the tumor and internalized into the cancer cells, under US irradiation, the sonosensitizer Ce6 rapidly induces extensive production of intracellular reactive oxygen species (ROS), thereby initiating a cascade amplified ROS-responsive activation of PBSN38 to release the active SN38 for inducing cell apoptosis. If some of the injected CPBSN38L is distributed into normal tissues, the inactive PBSN38 exerts no pharmacological activity on normal cells. CPBSN38L exhibited strong anticancer activity in multiple murine tumor models of colon adenocarcinoma and hepatocellular carcinoma with no chemotherapy-induced side effects, compared with the standard first-line anticancer drugs irinotecan and topotecan. CONCLUSIONS: This study established a side-effect-evitable, universal, and feasible strategy for cancer-targeting therapy.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Nanopartículas , Fotoquimioterapia , Pró-Fármacos , Humanos , Animais , Camundongos , Lipossomos , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Adenocarcinoma/tratamento farmacológico , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Nanopartículas/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
20.
J Couns Psychol ; 71(1): 77-87, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37870790

RESUMO

Higher therapy session frequency has been found to result in faster recovery, but few studies have considered that clients follow diverse trajectories of change in psychotherapy. It is unknown how session frequency may affect the sizes and shapes of change trajectories. The present study examined clients' change trajectories in weekly and biweekly therapy in a naturalistic setting, as well as predictors of these trajectories. Using a sample of 5,102 clients receiving 3-10 therapy sessions at a university counseling center, we identified 886 clients attending approximately weekly therapy and 1,753 clients attending approximately biweekly therapy. We examined the change trajectories of the weekly and biweekly samples using latent growth mixture modeling (LGMM). Three trajectories were identified in weekly therapy: slow change (78.33%), early improvement (17.61%), and worse before better (4.06%), and in biweekly therapy: slow change (80.38%), early improvement (13.52%), and worse before better (6.1%). The worse before better subgroup in weekly therapy experienced greater deterioration than those in biweekly therapy. The slow change and early improvement subgroups in weekly therapy showed treatment outcome comparable to those of their respective counterparts in biweekly therapy. Clients' intake symptoms, including eating concerns, frustration/anger, depression, and academic concerns, significantly predicted change trajectories. Compared to biweekly therapy, weekly therapy leads to higher chances of early improvement and shortens the duration of suffering but results in greater deterioration for individuals who deteriorate in therapy. The impact of session frequency on treatment outcome varies across clients, and session frequency should be adjusted individually. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Aconselhamento , Psicoterapia , Humanos , Psicoterapia/métodos , Resultado do Tratamento , Coleta de Dados , Relações Profissional-Paciente
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