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1.
Proc Natl Acad Sci U S A ; 121(18): e2314541121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38657049

RESUMO

Recent evidence has demonstrated that the transsynaptic nanoscale organization of synaptic proteins plays a crucial role in regulating synaptic strength in excitatory synapses. However, the molecular mechanism underlying this transsynaptic nanostructure in inhibitory synapses still remains unclear and its impact on synapse function in physiological or pathological contexts has not been demonstrated. In this study, we utilized an engineered proteolysis technique to investigate the effects of acute cleavage of neuroligin-2 (NL2) on synaptic transmission. Our results show that the rapid cleavage of NL2 led to impaired synaptic transmission by reducing both neurotransmitter release probability and quantum size. These changes were attributed to the dispersion of RIM1/2 and GABAA receptors and a weakened spatial alignment between them at the subsynaptic scale, as observed through superresolution imaging and model simulations. Importantly, we found that endogenous NL2 undergoes rapid MMP9-dependent cleavage during epileptic activities, which further exacerbates the decrease in inhibitory transmission. Overall, our study demonstrates the significant impact of nanoscale structural reorganization on inhibitory transmission and unveils ongoing modulation of mature GABAergic synapses through active cleavage of NL2 in response to hyperactivity.


Assuntos
Moléculas de Adesão Celular Neuronais , Proteínas do Tecido Nervoso , Sinapses , Transmissão Sináptica , Animais , Camundongos , Moléculas de Adesão Celular Neuronais/metabolismo , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Epilepsia/patologia , Hipocampo/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proteólise , Receptores de GABA-A/metabolismo , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
2.
Proc Natl Acad Sci U S A ; 121(11): e2400272121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437534

RESUMO

The endothelial lining of cerebral microvessels is damaged relatively early after cerebral ischemia/reperfusion (I/R) injury and mediates blood-brain barrier (BBB) disruption, neurovascular injury, and long-term neurological deficits. I/R induces BBB leakage within 1 h due to subtle structural alterations in endothelial cells (ECs), including reorganization of the actin cytoskeleton and subcellular redistribution of junctional proteins. Herein, we show that the protein peroxiredoxin-4 (Prx4) is an endogenous protectant against endothelial dysfunction and BBB damage in a murine I/R model. We observed a transient upregulation of Prx4 in brain ECs 6 h after I/R in wild-type (WT) mice, whereas tamoxifen-induced, selective knockout of Prx4 from endothelial cells (eKO) mice dramatically raised vulnerability to I/R. Specifically, eKO mice displayed more BBB damage than WT mice within 1 to 24 h after I/R and worse long-term neurological deficits and focal brain atrophy by 35 d. Conversely, endothelium-targeted transgenic (eTG) mice overexpressing Prx4 were resistant to I/R-induced early BBB damage and had better long-term functional outcomes. As demonstrated in cultures of human brain endothelial cells and in animal models of I/R, Prx4 suppresses actin polymerization and stress fiber formation in brain ECs, at least in part by inhibiting phosphorylation/activation of myosin light chain. The latter cascade prevents redistribution of junctional proteins and BBB leakage under conditions of Prx4 repletion. Prx4 also tempers microvascular inflammation and infiltration of destructive neutrophils and proinflammatory macrophages into the brain parenchyma after I/R. Thus, the evidence supports an indispensable role for endothelial Prx4 in safeguarding the BBB and promoting functional recovery after I/R brain injury.


Assuntos
Barreira Hematoencefálica , AVC Isquêmico , Animais , Humanos , Camundongos , Atrofia , Células Endoteliais , Endotélio , Peroxirredoxinas
3.
Blood ; 144(18): 1951-1961, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39046786

RESUMO

ABSTRACT: Although tyrosine kinase inhibitor (TKI) therapy has markedly improved the survival of people with chronic-phase chronic myeloid leukemia (CML), 20% to 30% of people still experienced therapy failure. Data from 1955 consecutive patients with chronic-phase CML diagnosed by the European LeukemiaNet recommendations from 1 center receiving initial imatinib or a second-generation (2G) TKI therapy were interrogated to develop a clinical prediction model for TKI-therapy failure. This model was subsequently validated in 3454 patients from 76 other centers. Using the predictive clinical covariates associated with TKI-therapy failure, we developed a model that stratified patients into low-, intermediate- and high-risk subgroups with significantly different cumulative incidences of therapy failure (P < .001). There was good discrimination and calibration in the external validation data set, and the performance was consistent with that of the training data set. Our model had the better prediction discrimination than the Sokal and European Treatment and Outcome Study long-term survival scores, with the greater time-dependent area under the receiver-operator characteristic curve values and a better ability to redefine the risk of therapy failure. Our model could help physicians estimate the likelihood of initial imatinib or 2G TKI-therapy failure in people with chronic-phase CML.


Assuntos
Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva , Inibidores de Proteínas Quinases , Falha de Tratamento , Humanos , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Pessoa de Meia-Idade , Masculino , Feminino , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Idoso , Adulto , Mesilato de Imatinib/uso terapêutico , Idoso de 80 Anos ou mais , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Pirimidinas/efeitos adversos , Adulto Jovem , Adolescente , Benzamidas/uso terapêutico , Piperazinas/uso terapêutico , Piperazinas/efeitos adversos , Prognóstico , Antineoplásicos/uso terapêutico , Antineoplásicos/efeitos adversos
4.
Arterioscler Thromb Vasc Biol ; 44(7): 1540-1554, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38660802

RESUMO

BACKGROUND: Myxomatous valve disease (MVD) is the most common cause of mitral regurgitation, leading to impaired cardiac function and heart failure. MVD in a mouse model of Marfan syndrome includes valve leaflet thickening and progressive valve degeneration. However, the underlying mechanisms by which the disease progresses remain undefined. METHODS: Mice with Fibrillin 1 gene variant Fbn1C1039G/+ recapitulate histopathologic features of Marfan syndrome, and Wnt (Wingless-related integration site) signaling activity was detected in TCF/Lef-lacZ (T-cell factor/lymphoid enhancer factor-ß-galactosidase) reporter mice. Single-cell RNA sequencing was performed from mitral valves of wild-type and Fbn1C1039G/+ mice at 1 month of age. Inhibition of Wnt signaling was achieved by conditional induction of the secreted Wnt inhibitor Dkk1 (Dickkopf-1) expression in periostin-expressing valve interstitial cells of Periostin-Cre; tetO-Dkk1; R26rtTA; TCF/Lef-lacZ; Fbn1C1039G/+ mice. Dietary doxycycline was administered for 1 month beginning with MVD initiation (1-month-old) or MVD progression (2-month-old). Histological evaluation and immunofluorescence for ECM (extracellular matrix) and immune cells were performed. RESULTS: Wnt signaling is activated early in mitral valve disease progression, before immune cell infiltration in Fbn1C1039G/+ mice. Single-cell transcriptomics revealed similar mitral valve cell heterogeneity between wild-type and Fbn1C1039G/+ mice at 1 month of age. Wnt pathway genes were predominantly expressed in valve interstitial cells and valve endothelial cells of Fbn1C1039G/+ mice. Inhibition of Wnt signaling in Fbn1C1039G/+ mice at 1 month of age prevented the initiation of MVD as indicated by improved ECM remodeling and reduced valve leaflet thickness with decreased infiltrating macrophages. However, later, Wnt inhibition starting at 2 months did not prevent the progression of MVD. CONCLUSIONS: Wnt signaling is involved in the initiation of mitral valve abnormalities and inflammation but is not responsible for later-stage valve disease progression once it has been initiated. Thus, Wnt signaling contributes to MVD progression in a time-dependent manner and provides a promising therapeutic target for the early treatment of congenital MVD in Marfan syndrome.


Assuntos
Modelos Animais de Doenças , Progressão da Doença , Fibrilina-1 , Valva Mitral , Via de Sinalização Wnt , Animais , Fibrilina-1/genética , Fibrilina-1/metabolismo , Valva Mitral/metabolismo , Valva Mitral/patologia , Valva Mitral/efeitos dos fármacos , Camundongos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos Transgênicos , Síndrome de Marfan/genética , Síndrome de Marfan/complicações , Síndrome de Marfan/metabolismo , Síndrome de Marfan/patologia , Insuficiência da Valva Mitral/patologia , Insuficiência da Valva Mitral/metabolismo , Insuficiência da Valva Mitral/prevenção & controle , Insuficiência da Valva Mitral/genética , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Inflamação/genética , Masculino , Feminino , Moléculas de Adesão Celular , Adipocinas
5.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38185991

RESUMO

Intracranial electrical stimulation (iES) of auditory cortex can elicit sound experiences with a variety of perceived contents (hallucination or illusion) and locations (contralateral or bilateral side), independent of actual acoustic inputs. However, the neural mechanisms underlying this elicitation heterogeneity remain undiscovered. Here, we collected subjective reports following iES at 3062 intracranial sites in 28 patients (both sexes) and identified 113 auditory cortical sites with iES-elicited sound experiences. We then decomposed the sound-induced intracranial electroencephalogram (iEEG) signals recorded from all 113 sites into time-frequency features. We found that the iES-elicited perceived contents can be predicted by the early high-γ features extracted from sound-induced iEEG. In contrast, the perceived locations elicited by stimulating hallucination sites and illusion sites are determined by the late high-γ and long-lasting α features, respectively. Our study unveils the crucial neural signatures of iES-elicited sound experiences in human and presents a new strategy to hearing restoration for individuals suffering from deafness.


Assuntos
Córtex Auditivo , Ilusões , Masculino , Feminino , Humanos , Córtex Auditivo/fisiologia , Ilusões/fisiologia , Estimulação Acústica , Mapeamento Encefálico , Estimulação Elétrica , Alucinações
6.
J Am Chem Soc ; 146(14): 9506-9511, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557065

RESUMO

Clusters showing a giant magnetocaloric effect (MCE) are of interest as molecular coolants for magnetic refrigeration. Herein, we report two heterometallic clusters, denoted as Gd152Ni14@Cl24 and Sm152Ni8, just to highlight their inorganic core motifs, obtained by ligand-controlled co-hydrolysis of Ni2+ and Ln3+ (Ln = Gd, Sm) in the presence of N-(2-hydroxyethyl)iminodiacetic acid (H2HEIDA). Both clusters display fascinating cubic Tinkertoy-like structures, with the core motifs being built of multiple metallic shells of Platonic and Archimedean polyhedra. The isothermal magnetic entropy change─a direct measurement of MCE─was determined to be 52.65 J·kg-1·K-1 at 2.5 K and 7.0 T for the Gd-containing cluster; this value is the highest known for any molecular clusters so far reported.

7.
Br J Haematol ; 204(4): 1393-1401, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38168845

RESUMO

Cytomegalovirus (CMV) DNAemia and disease are common complications in patients undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT). Few studies have compared the efficacy and safety of the HSCT donor and third-party CMV-specific cytotoxic T lymphocytes (CMV-CTLs) in the treatment of CMV DNAemia and disease. In this study, we retrospectively compared the efficacy and safety of HSCT donor and third-party CMV-CTLs in patients with refractory CMV DNAemia or disease after allo-HSCT at our centre from January 2017 to September 2021. Fifty-three patients who received CMV-CTL therapy were enrolled, including 40 in the donor group and 13 in the third-party group, and they were adults aged 18 years or older. Within 6 weeks of treatment, 26 (65.0%) and 9 (69.2%) patients achieved complete response in the donor and third-party groups (p = 1.000). The 2-year overall survival was 59.6% (95% CI 46.1%-77.1%) and 53.8% (32.6%-89.1%) in the donor and third-party groups (p = 0.860). Four (10.0%) patients in the donor group and two (15.4%) patients in the third-party group developed acute graft-versus-host disease within 3 months after CMV-CTL infusions. In conclusion, our data suggest that donor and third-party CMV-CTLs have comparable efficacy and safety for refractory CMV DNAemia and disease.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Citomegalovirus , Linfócitos T Citotóxicos , Infecções por Citomegalovirus/terapia , Infecções por Citomegalovirus/complicações , Estudos Retrospectivos , Transplante Homólogo/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
8.
Br J Haematol ; 204(2): 628-637, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38050437

RESUMO

This PASS-ALL study was designed to explore the effect of paediatric-inspired versus adult chemotherapy regimens on survival of adolescents and young adults (AYA) with high-risk Philadelphia chromosome-negative B-cell acute lymphoblastic leukaemia (HR PH-ve B-cell ALL) eligible for allogeneic haematopoietic stem cell transplantation (allo-HSCT). The PASS-ALL study is a multicentre, observational cohort study, and 143 patients with HR B-cell PH-ve ALL were enrolled from five centres-77 patients allocated in the paediatric-inspired cohort and 66 in the adult cohort with comparable baseline characteristics. Of the 143 patients, 128 cases underwent allo-HSCT. Three-year leukaemia-free survival (LFS) in the paediatric-inspired cohort was 72.2% (95% CI 60.8%-83.6%) compared with 44.6% (95% CI 31.9%-57.3%; p = 0.001). Furthermore, time-to-positive minimal residual disease (TTP-MRD) post-HSCT was marked different, 3-year cumulative incidence of relapse was 25.9% (95% CI 15.8%-37.2%) in paediatric cohort and 45.4% (95% CI 40.0%-57.9%) in adult cohort (p = 0.026). Finally, the 3-year OS rate was 75.3% (95% CI 64.9%-85.7%) for the paediatric-inspired cohort and 64.1% (95% CI 51.8%-76.4%) for the adult cohort (p = 0.074). On a multivariate analysis, paediatric-inspired regimen is a predictive factor for LFS (HR = 2.540, 95% CI 1.327-4.862, p = 0.005). Collectively, our data suggest that paediatric-inspired chemotherapy pre-HSCT results in deeper and durable MRD response reduces relapse post-HSCT and improves survival in HR B-cell PH-ve ALL patients with allo-HSCT.


Assuntos
Linfoma de Burkitt , Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Adulto Jovem , Humanos , Criança , Cromossomo Filadélfia , Recidiva Local de Neoplasia , Transplante de Células-Tronco Hematopoéticas/métodos , Recidiva , Estudos Retrospectivos
9.
BMC Med ; 22(1): 176, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664766

RESUMO

BACKGROUND: There is an urgent unmet need for effective initial treatment for acute graft-versus-host disease (aGVHD) adding to the standard first-line therapy with corticosteroids after allogeneic haematopoietic stem cell transplantation (allo-HSCT). METHODS: We performed a multicentre, open-label, randomized, phase 3 study. Eligible patients (aged 15 years or older, had received allo-HSCT for a haematological malignancy, developed aGVHD, and received no previous therapies for aGVHD) were randomly assigned (1:1) to receive either 5 mg/m2 MTX on Days 1, 3, or 8 and then combined with corticosteroids or corticosteroids alone weekly. RESULTS: The primary endpoint was the overall response rate (ORR) on Day 10. A total of 157 patients were randomly assigned to receive either MTX plus corticosteroids (n = 78; MTX group) or corticosteroids alone (n = 79; control group). The Day 10 ORR was 97% for the MTX group and 81% for the control group (p = .005). Among patients with mild aGVHD, the Day 10 ORR was 100% for the MTX group and 86% for the control group (p = .001). The 1-year estimated failure-free survival was 69% for the MTX group and 41% for the control group (p = .002). There were no differences in treatment-related adverse events between the two groups. CONCLUSIONS: In conclusion, mini-dose MTX combined with corticosteroids can significantly improve the ORR in patients with aGVHD and is well tolerated, although it did not achieve the prespecified 20% improvement with the addition of MTX. TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov (NCT04960644).


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Metotrexato , Metilprednisolona , Humanos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Feminino , Masculino , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Adulto , Metilprednisolona/uso terapêutico , Metilprednisolona/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto Jovem , Resultado do Tratamento , Quimioterapia Combinada , Idoso , Adolescente , Doença Aguda
10.
J Intern Med ; 295(2): 216-228, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37899297

RESUMO

BACKGROUND: Patients with relapsed or refractory acute myeloid leukemia (R/R AML) and FLT3-internal tandem duplication (FLT3-ITD) respond infrequently to salvage chemotherapy. OBJECTIVE: To investigate the efficacy of sorafenib plus triplet therapy with venetoclax, azacitidine, and homoharringtonine (VAH) as a salvage therapy in this population. METHODS: This multicenter, single-arm, phase 2 study was conducted at 12 hospitals across China. Eligible patients had R/R AML with FLT3-ITD (aged 18-65 years) who were treated with VAH. The primary endpoint was composite complete remission (CRc) after two cycles. Secondary outcomes included the overall response rate (ORR), safety, and survival. RESULTS: Between July 9, 2020, and March 19, 2022, 58 patients were assessed for eligibility, 51 of whom were enrolled. The median patient age was 47 years (interquartile range [IQR] 31-57). CRc was 76.5% with ORR of 82.4%. At a median follow-up of 17.7 months (IQR, 8.7-24.7), the median duration of CRc was not reached (NR), overall survival was 18.1 months (95% confidence interval [CI], 11.8-NR) and event-free survival was 11.4 months (95% CI, 5.6-NR). Grade 3 or 4 adverse events occurring in ≥10% of patients included neutropenia in 47 (92.2%), thrombocytopenia in 41 (80.4%), anemia in 35 (68.6%), febrile neutropenia in 29 (56.9%), pneumonia in 13 (25.5%), and sepsis in 6 (11.8%) patients. Treatment-related death occurred in two (3.9%) patients. CONCLUSIONS: The sorafenib plus VAH regimen was well tolerated and highly active against R/R AML with FLT3-ITD. This regimen may be a suitable therapeutic option for this population, but larger population trials are needed to be explored. TRIAL REGISTRATION: Clinical Trials Registry: NCT04424147.


Assuntos
Azacitidina , Compostos Bicíclicos Heterocíclicos com Pontes , Leucemia Mieloide Aguda , Sulfonamidas , Humanos , Azacitidina/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/uso terapêutico , Mepesuccinato de Omacetaxina/uso terapêutico , Leucemia Mieloide Aguda/terapia , Resposta Patológica Completa , Sorafenibe/efeitos adversos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
11.
Small ; 20(44): e2402655, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38949408

RESUMO

Solution Gated Graphene Field-Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra-sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light-matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution-gated graphene field-effect transistor (PEC-SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o-phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time-integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC-SGGT, inherently equipped with built-in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof-of-concept for the feasibility of light-assisted functionalized gate-controlled PEC-SGGT for small molecule detection.


Assuntos
Grafite , Organofosfatos , Transistores Eletrônicos , Grafite/química , Organofosfatos/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Eletrodos , Soluções
12.
Genet Med ; 26(8): 101167, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38770750

RESUMO

PURPOSE: Rare genetic variants in the PURA gene cause the PURA-related neurodevelopmental disorder (PURA-NDD), characterized by neonatal abnormalities and developmental delay. Using genome-wide DNA methylation analysis on patients with PURA variants, we aim to establish a PURA-NDD-specific methylation profile and provide further insights on the molecular basis of the PURA-NDD. METHODS: Twenty three individuals (including 12 unpublished) carrying PURA variants were enrolled. We conducted the Illumina Infinium EPIC microarray analysis in 17 PURA-NDD individuals. In vitro experiments were performed to examine how PURA variants affect Pur-a expression. RESULTS: Additional phenotypes in 12 newly identified patients were described in this study. Genome-wide DNA methylation analysis unveiled distinctive methylation profiles to PURA-NDD, and the established classifier can reclassify PURA variants of uncertain significance. Patients bearing PURA hapoloinsufficient and missense variants have comparable DNA methylation profiles, and cells expressing these PURA variants showed consistent Pur-a downregulation, suggesting a haploinsufficiency mechanism. CONCLUSION: Patients with PURA-NDD exhibit a specific episignature, which has potential to aid identification and diagnosis of PURA-NDD patients and offer implications for further functional investigations.


Assuntos
Metilação de DNA , Epigênese Genética , Transtornos do Neurodesenvolvimento , Humanos , Transtornos do Neurodesenvolvimento/genética , Metilação de DNA/genética , Feminino , Epigênese Genética/genética , Masculino , Criança , Pré-Escolar , Estudo de Associação Genômica Ampla , Fenótipo , Haploinsuficiência/genética , Lactente
13.
New Phytol ; 243(6): 2251-2264, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39073105

RESUMO

The shape of rice grains not only determines the thousand-grain weight but also correlates closely with the grain quality. Here we identified an ultra-large grain accession (ULG) with a thousand-grain weight exceeding 60 g. The integrated analysis of QTL, BSA, de novo genome assembled, transcription sequencing, and gene editing was conducted to dissect the molecular basis of the ULG formation. The ULG pyramided advantageous alleles from at least four known grain-shaping genes, OsLG3, OsMADS1, GS3, GL3.1, and one novel locus, qULG2-b, which encoded a leucine-rich repeat receptor-like kinase. The collective impacts of OsLG3, OsMADS1, GS3, and GL3.1 on grain size were confirmed in transgenic plants and near-isogenic lines. The transcriptome analysis identified 112 genes cooperatively regulated by these four genes that were prominently involved in photosynthesis and carbon metabolism. By leveraging the pleiotropy of these genes, we enhanced the grain yield, appearance, and stress tolerance of rice var. SN265. Beyond showcasing the pyramiding of multiple grain size regulation genes that can produce ULG, our study provides a theoretical framework and valuable genomic resources for improving rice variety by leveraging the pleiotropy of grain size regulated genes.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , Oryza , Locos de Características Quantitativas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Genes de Plantas , Plantas Geneticamente Modificadas , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fenótipo , Alelos , Estresse Fisiológico/genética
14.
Plant Physiol ; 192(1): 307-325, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36755501

RESUMO

Y900 is one of the top hybrid rice (Oryza sativa) varieties, with its yield exceeding 15 t·hm-2. To dissect the mechanism of heterosis, we sequenced the male parent line R900 and female parent line Y58S using long-read and Hi-C technology. High-quality reference genomes of 396.41 Mb and 398.24 Mb were obtained for R900 and Y58S, respectively. Genome-wide variations between the parents were systematically identified, including 1,367,758 single-nucleotide polymorphisms, 299,149 insertions/deletions, and 4,757 structural variations. The level of variation between Y58S and R900 was the lowest among the comparisons of Y58S with other rice genomes. More than 75% of genes exhibited variation between the two parents. Compared with other two-line hybrids sharing the same female parent, the portion of Geng/japonica (GJ)-type genetic components from different male parents increased with yield increasing in their corresponding hybrids. Transcriptome analysis revealed that the partial dominance effect was the main genetic effect that constituted the heterosis of Y900. In the hybrid, both alleles from the two parents were expressed, and their expression patterns were dynamically regulated in different tissues. The cis-regulation was dominant for young panicle tissues, while trans-regulation was more common in leaf tissues. Overdominance was surprisingly prevalent in stems and more likely regulated by the trans-regulation mechanism. Additionally, R900 contained many excellent GJ haplotypes, such as NARROW LEAF1, Oryza sativa SQUAMOSA PROMOTER BINDING PROTEIN-LIKE13, and Grain number, plant height, and heading date8, making it a good complement to Y58S. The fine-tuned mechanism of heterosis involves genome-wide variation, GJ introgression, key functional genes, and dynamic gene/allele expression and regulation pattern changes in different tissues and growth stages.


Assuntos
Vigor Híbrido , Oryza , Vigor Híbrido/genética , Oryza/genética , Perfilação da Expressão Gênica , Hibridização Genética
15.
Toxicol Appl Pharmacol ; 485: 116890, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492674

RESUMO

Ricin (ricin toxin, RT) has the potential to cause damage to multiple organs and systems. Currently, there are no existing antidotes, vaccinations, or effective therapies to prevent or treat RT intoxication. Apart from halting protein synthesis, RT also induces oxidative stress, inflammation and autophagy. To explore the mechanisms of RT-induced inflammatory injury and specific targets of prevention and treatment for RT poisoning, we characterized the role of cross-talk between autophagy and NLRP3 inflammasome in RT-induced damage and elucidated the underlying mechanisms. We showed that RT-induced inflammation was attributed to activation of the TLR4/MyD88/NLRP3 signaling and ROS production, evidenced by increased ASC speck formation and attenuated TXNIP/TRX-1 interaction, as well as pre-treatment with MCC950, MyD88 knockdown and NAC significantly reduced IL-1ß, IL-6 and TNF-α mRNA expression. In addition, autophagy is also enhanced in RT-triggered MLE-12 cells. RT elevated the levels of ATG5, p62 and Beclin1 protein, provoked the accumulation of LC3 puncta detected by immunofluorescence staining. Treatment with rapamycin (Rapa) reversed the RT-caused TLR4/MyD88/NLRP3 signaling activation, ASC specks formation as well as the levels of IL-1ß, IL-6 and TNF-α mRNA. In conclusion, RT promoted NLRP3 inflammasome activation and autophgay. Inflammation induced by RT was attenuated by autophagy activation, which suppressed the NLRP3 inflammasome. These findings suggest Rapa as a potential therapeutic drug for the treatment of RT-induced inflammation-related diseases.


Assuntos
Autofagia , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ricina , Transdução de Sinais , Autofagia/efeitos dos fármacos , Animais , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Ricina/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/induzido quimicamente , Linhagem Celular , Receptor 4 Toll-Like/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo
16.
Theor Appl Genet ; 137(7): 154, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856926

RESUMO

KEY MESSAGE: Our findings highlight a valuable breeding resource, demonstrating the potential to concurrently enhance grain shape, thermotolerance, and alkaline tolerance by manipulating Gγ protein in rice. Temperate Geng/Japonica (GJ) rice yields have improved significantly, bolstering global food security. However, GJ rice breeding faces challenges, including enhancing grain quality, ensuring stable yields at warmer temperatures, and utilizing alkaline land. In this study, we employed CRISPR/Cas9 gene-editing technology to knock out the GS3 locus in seven elite GJ varieties with superior yield performance. Yield component measurements revealed that GS3 knockout mutants consistently enhanced grain length and reduced plant height in diverse genetic backgrounds. The impact of GS3 on the grain number per panicle and setting rate depended on the genetic background. GS3 knockout did not affect milling quality and minimally altered protein and amylose content but notably influenced chalkiness-related traits. GS3 knockout indiscriminately improved heat and alkali stress tolerance in the GJ varieties studied. Transcriptome analysis indicated differential gene expression between the GS3 mutants and their wild-type counterparts, enriched in biological processes related to photosynthesis, photosystem II stabilization, and pathways associated with photosynthesis and cutin, suberine, and wax biosynthesis. Our findings highlight GS3 as a breeding resource for concurrently improving grain shape, thermotolerance, and alkaline tolerance through Gγ protein manipulation in rice.


Assuntos
Grão Comestível , Oryza , Melhoramento Vegetal , Proteínas de Plantas , Termotolerância , Álcalis , Sistemas CRISPR-Cas , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Edição de Genes , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Termotolerância/genética
17.
Theor Appl Genet ; 137(10): 230, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39320412

RESUMO

KEY MESSAGE: Two major QTLs for cold tolerance in pumpkin were localised, and CmoERF017 was identified as a key candidate gene within these QTLs via RNA-seq. Functional analysis revealed that CmoERF017 was a positive regulator of pumpkin in response to low-temperature stress. Low temperature is a key environmental factor that affects the protected cultivation of cucumber (Cucumis sativus L.) in winter, and the cold tolerance of cucumber/pumpkin-grafted seedlings depends on the rootstock. Pumpkin (Cucurbita spp.) has a well-developed root system, high resistance and wide adaptation, commonly used as rootstock for cucumber to improve the cold tolerance of grafted seedlings. This study used two high-generation inbred lines of Cucurbita moschata with significant differences in cold tolerance. We identified key candidate genes within the major cold tolerance QTL of rootstocks using QTL-seq and RNA-seq and investigated the function and molecular mechanisms of these genes in response to low-temperature stress. Results showed that QTL-seq located two cold tolerance QTLs, qCII-1 and qCII-2, while RNA-seq located 28 differentially expressed genes within these QTLs. CmoERF017 was finally identified as a key candidate gene. Functional validation results indicated that CmoERF017 is a positive regulator of pumpkin in response to low-temperature stress and affected root ABA synthesis and signalling by directly regulating the expression of SDR7 and ABI5. This study identified a key gene for low-temperature stress tolerance in rootstock pumpkin and clarified its role in the molecular mechanism of hormone-mediated plant cold tolerance. The study findings enrich the theoretical understanding of low-temperature stress tolerance in pumpkin and are valuable for the selection and breeding of cold-tolerant varieties of pumpkin used for rootstocks.


Assuntos
Mapeamento Cromossômico , Temperatura Baixa , Cucurbita , Proteínas de Plantas , Locos de Características Quantitativas , Fatores de Transcrição , Cucurbita/genética , Cucurbita/crescimento & desenvolvimento , Cucurbita/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Genes de Plantas
18.
Eur Radiol ; 34(10): 6376-6383, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38652159

RESUMO

OBJECTIVES: To investigate microvascular changes in juvenile localised scleroderma (JLS) lesions using superb microvascular imaging (SMI) and assess SMI's utility in evaluating disease activity. METHODS: This prospective study enroled 16 children (7 males) with pathologically diagnosed JLS between January 2021 and June 2023. Lesions were assessed using Localised Scleroderma Cutaneous Assessment Tools, including the localised scleroderma skin activity index (LoSAI) and localised scleroderma skin damage index (LoSDI). Lesions with LoSAI scores > 0 were classified as active. The thickness and blood flow of the lesions and healthy skin layers of the contralateral site were evaluated using ultrasound. SMI was used to detect microvascular blood flow in the lesions and healthy skin, and the vascular index (VI) was calculated. The difference in VI between active lesions and healthy skin was correlated with LoSAI and total scores. RESULTS: Of 46 lesions, 23 were active and 23 inactive. The skin thickness of the lesion was 0.094 ± 0.024 cm, and that of the healthy site was 0.108 ± 0.026 cm (p < 0.001). The VI of the active lesions and healthy skin were 7.60 (3.60, 12.80)% and 1.10 (0.50, 2.10)%, respectively (p < 0.001). The VI of the inactive lesions and the healthy skin were 0.85 (0.00, 2.20)% and 1.60 (1.00, 3.10)%, respectively (p = 0.011). VI differences between active lesions and healthy skin positively correlated with the LoSAI clinical score (r = 0.625, p = 0.001) and total score (r = 0.842, p < 0.001). CONCLUSION: SMI can quantitatively detect microvascular blood flow changes in JLS skin, indicating lesion activity and severity. CLINICAL RELEVANCE STATEMENT: SMI is a convenient, non-invasive, technique for detecting active JLS lesions and can provide valuable information to guide treatment options. KEY POINTS: Current grading systems of juvenile localised scleroderma rely on subjective clinical information. Superb Microvascular Imaging identified that vascular indexes between active lesions and healthy skin positively correlated with clinical scores. Superb Microvascular Imaging effectively assesses microvascular blood flow, aiding juvenile localised scleroderma lesion activity evaluation.


Assuntos
Microvasos , Esclerodermia Localizada , Pele , Humanos , Masculino , Feminino , Esclerodermia Localizada/diagnóstico por imagem , Estudos Prospectivos , Criança , Microvasos/diagnóstico por imagem , Adolescente , Pele/irrigação sanguínea , Pele/diagnóstico por imagem , Ultrassonografia/métodos , Índice de Gravidade de Doença , Pré-Escolar
19.
Inorg Chem ; 63(43): 20781-20791, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39411888

RESUMO

It remains a challenging issue to achieve durably stable photocatalytic CO2 reduction over heterojunctions owing to their inherent structural assembly features. Herein, a unique partial encapsulation architecture is fabricated on the 3D/2D CoWO4/C3N5 heterojunction by embedding CoWO4 microspheres on C3N5 nanosheets, which achieves efficient, durable, stable, and selective photocatalytic CO2 reduction. For the optimal 5%-CoWO4/C3N5 heterojunction, the yield of selective CO2 reduction to CO is 7.70 and 3.82 times higher than those of CoWO4 and C3N5 in 4 h, respectively, and it maintains a stable CO generation rate within 20 cycles over 80 h. A series of characterization experiments and density functional theory calculations reveal that the structural stability is reinforced significantly via strong interfacial interaction owing to the unique partial encapsulation architecture fabricated on the 3D/2D CoWO4/C3N5 heterojunction, the separation efficiency of photogenerated carriers is improved by inducing a built-in electric field and triggering the S-scheme charge-transport path, and the high CO product selectivity is attributed to the much lower free energy required for the generation path of CO compared to that for CH4.

20.
Inorg Chem ; 63(20): 9058-9065, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38720438

RESUMO

Nitrofurans are important synthetic broad-spectrum antibacterial drugs with the basic structure of 5-nitrofuran. Due to their toxicity, it is essential to develop a sensitive sensor with strong anti-interference capabilities for their detection. In this work, two {P4Mo6O31}12--based compounds, [H4(HPTTP)]2{CuI[Mo12O24(OH)6(PO4)3(HPO4)(H2PO4)4]}·xH2O (x = 13 for (1), 7 for (2); HPTTP = 4,4',4″,4‴-(1H-pyrrole-2,3,4,5-tetrayl)tetrapyridine), exhibiting similar coordination but distinct stacking modes. Both compounds were synthesized and used for the electrochemical detection of nitrofuran antibiotics. The tetrapyridine-based ligand was generated in situ during assembly, and its potential mechanism was discussed. Composite electrode materials, formed by mixing graphite powder with compounds 1-2 and physically grinding them, proved to be highly effective in the electrochemical trace detection of furazolidone (FZD) and furaltadone hydrochloride (FTD·HCl) under optimal conditions. Besides, the possible electrochemical detection mechanisms of two nitro-antibiotics were studied.


Assuntos
Antibacterianos , Complexos de Coordenação , Cobre , Nitrofuranos , Polímeros , Antibacterianos/química , Antibacterianos/análise , Ligantes , Nitrofuranos/análise , Nitrofuranos/química , Cobre/química , Cobre/análise , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Polímeros/química , Molibdênio/química , Piridinas/química , Estrutura Molecular , Técnicas Eletroquímicas , Modelos Moleculares
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