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1.
Cell ; 184(5): 1156-1170.e14, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33539781

RESUMEN

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.


Asunto(s)
Productos Agrícolas/genética , Domesticación , Oryza/genética , Sistemas CRISPR-Cas , Seguridad Alimentaria , Edición Génica , Variación Genética , Genoma de Planta , Oryza/clasificación , Poliploidía
2.
Cell ; 146(5): 772-84, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21871655

RESUMEN

T cell differentiation into distinct functional effector and inhibitory subsets is regulated, in part, by the cytokine environment present at the time of antigen recognition. Here, we show that hypoxia-inducible factor 1 (HIF-1), a key metabolic sensor, regulates the balance between regulatory T cell (T(reg)) and T(H)17 differentiation. HIF-1 enhances T(H)17 development through direct transcriptional activation of RORγt and via tertiary complex formation with RORγt and p300 recruitment to the IL-17 promoter, thereby regulating T(H)17 signature genes. Concurrently, HIF-1 attenuates T(reg) development by binding Foxp3 and targeting it for proteasomal degradation. Importantly, this regulation occurs under both normoxic and hypoxic conditions. Mice with HIF-1α-deficient T cells are resistant to induction of T(H)17-dependent experimental autoimmune encephalitis associated with diminished T(H)17 and increased T(reg) cells. These findings highlight the importance of metabolic cues in T cell fate determination and suggest that metabolic modulation could ameliorate certain T cell-based immune pathologies.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Linfocitos T Reguladores/citología , Células Th17/citología , Animales , Secuencia de Bases , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/metabolismo , Factores de Transcripción Forkhead/metabolismo , Humanos , Factor 1 Inducible por Hipoxia/metabolismo , Interleucina-17/genética , Interleucina-17/inmunología , Células Jurkat , Ratones , Datos de Secuencia Molecular , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Factor de Transcripción STAT3/metabolismo , Alineación de Secuencia , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Factores de Transcripción p300-CBP/metabolismo
3.
Nature ; 583(7815): 277-281, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32528176

RESUMEN

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.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Compuestos Heterocíclicos con 3 Anillos/metabolismo , Lactonas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Transducción de Señal/genética , Transcripción Genética , Antocianinas/biosíntesis , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Genes de Plantas/genética , Reguladores del Crecimiento de las Plantas/biosíntesis , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Brotes de la Planta/genética , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(19): e2219098120, 2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37126725

RESUMEN

Graphene oxide (GO) membranes with nanoconfined interlayer channels theoretically enable anomalous nanofluid transport for ultrahigh filtration performance. However, it is still a significant challenge for current GO laminar membranes to achieve ultrafast water permeation and high ion rejection simultaneously, because of the contradictory effect that exists between the water-membrane hydrogen-bond interaction and the ion-membrane electrostatic interaction. Here, we report a vertically aligned reduced GO (VARGO) membrane and propose an electropolarization strategy for regulating the interfacial hydrogen-bond and electrostatic interactions to concurrently enhance water permeation and ion rejection. The membrane with an electro-assistance of 2.5 V exhibited an ultrahigh water permeance of 684.9 L m-2 h-1 bar-1, which is 1-2 orders of magnitude higher than those of reported GO-based laminar membranes. Meanwhile, the rejection rate of the membrane for NaCl was as high as 88.7%, outperforming most reported graphene-based membranes (typically 10 to 50%). Molecular dynamics simulations and density-function theory calculations revealed that the electropolarized VARGO nanochannels induced the well-ordered arrangement of nanoconfined water molecules, increasing the water transport efficiency, and thereby resulting in improved water permeation. Moreover, the electropolarization effect enhanced the surface electron density of the VARGO nanochannels and reinforced the interfacial attractive interactions between the cations in water and the oxygen groups and π-electrons on the VARGO surface, strengthening the ion-partitioning and Donnan effect for the electrostatic exclusion of ions. This finding offers an electroregulation strategy for membranes to achieve both high water permeability and high ion rejection performance.

5.
Proc Natl Acad Sci U S A ; 120(28): e2301115120, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399418

RESUMEN

Enteric bacterial pathogens pose significant threats to human health; however, the mechanisms by which they infect the mammalian gut in the face of daunting host defenses and an established microbiota remain poorly defined. For the attaching and effacing (A/E) bacterial family member and murine pathogen Citrobacter rodentium, its virulence strategy likely involves metabolic adaptation to the host's intestinal luminal environment, as a necessary precursor to reach and infect the mucosal surface. Suspecting this adaptation involved the intestinal mucus layer, we found that C. rodentium was able to catabolize sialic acid, a monosaccharide derived from mucins, and utilize it as its sole carbon source for growth. Moreover, C. rodentium also sensed and displayed chemotactic activity toward sialic acid. These activities were abolished when the nanT gene, encoding a sialic acid transporter, was deleted (ΔnanT). Correspondingly, the ΔnanT C. rodentium strain was significantly impaired in its ability to colonize the murine intestine. Intriguingly, sialic acid was also found to induce the secretion of two autotransporter proteins, Pic and EspC, which possess mucinolytic and host-adherent properties. As a result, sialic acid enhanced the ability of C. rodentium to degrade intestinal mucus (through Pic), as well as to adhere to intestinal epithelial cells (through EspC). We thus demonstrate that sialic acid, a monosaccharide constituent of the intestinal mucus layer, functions as an important nutrient and a key signal for an A/E bacterial pathogen to escape the colonic lumen and directly infect its host's intestinal mucosa.


Asunto(s)
Citrobacter rodentium , Infecciones por Enterobacteriaceae , Animales , Ratones , Bacterias , Citrobacter , Infecciones por Enterobacteriaceae/microbiología , Mucosa Intestinal/microbiología , Mamíferos , Monosacáridos , Ácido N-Acetilneuramínico
6.
Proc Natl Acad Sci U S A ; 120(30): e2220296120, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37459535

RESUMEN

Metastasis, especially intrahepatic, is a major challenge for hepatocellular carcinoma (HCC) treatment. Cytoskeleton remodeling has been identified as a vital process mediating intrahepatic spreading. Previously, we reported that HCC tumor adhesion and invasion were modulated by circular RNA (circRNA), which has emerged as an important regulator of various cellular processes and has been implicated in cancer progression. Here, we uncovered a nuclear circRNA, circASH2, which is preferentially lost in HCC tissues and inhibits HCC metastasis by altering tumor cytoskeleton structure. Tropomyosin 4 (TPM4), a critical binding protein of actin, turned out to be the major target of circASH2 and was posttranscriptionally suppressed. Such regulation is based on messenger RNA (mRNA)/precursormRNA splicing and degradation process. Furthermore, liquid-liquid phase separation of nuclear Y-box binding protein 1 (YBX1) enhanced by circASH2 augments TPM4 transcripts decay. Together, our data have revealed a tumor-suppressive circRNA and, more importantly, uncovered a fine regulation mechanism for HCC progression.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Humanos , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/patología , ARN Circular/genética , ARN Circular/metabolismo , ARN Mensajero , Proliferación Celular/genética , Proteínas del Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Línea Celular Tumoral , Proteína 1 de Unión a la Caja Y/genética
7.
Proc Natl Acad Sci U S A ; 120(19): e2220622120, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37126676

RESUMEN

The sedentary lifestyle and refined food consumption significantly lead to obesity, type 2 diabetes, and related complications, which have become one of the major threats to global health. This incidence could be potentially reduced by daily foods rich in resistant starch (RS). However, it remains a challenge to breed high-RS rice varieties. Here, we reported a high-RS mutant rs4 with an RS content of ~10.8% in cooked rice. The genetic study revealed that the loss-of-function SSIIIb and SSIIIa together with a strong Wx allele in the background collaboratively contributed to the high-RS phenotype of the rs4 mutant. The increased RS contents in ssIIIa and ssIIIa ssIIIb mutants were associated with the increased amylose and lipid contents. SSIIIb and SSIIIa proteins were functionally redundant, whereas SSIIIb mainly functioned in leaves and SSIIIa largely in endosperm owing to their divergent tissue-specific expression patterns. Furthermore, we found that SSIII experienced duplication in different cereals, of which one SSIII paralog was mainly expressed in leaves and another in the endosperm. SSII but not SSIV showed a similar evolutionary pattern to SSIII. The copies of endosperm-expressed SSIII and SSII were associated with high total starch contents and low RS levels in the seeds of tested cereals, compared with low starch contents and high RS levels in tested dicots. These results provided critical genetic resources for breeding high-RS rice cultivars, and the evolutionary features of these genes may facilitate to generate high-RS varieties in different cereals.


Asunto(s)
Diabetes Mellitus Tipo 2 , Oryza , Almidón Sintasa , Almidón Resistente/metabolismo , Oryza/genética , Almidón Sintasa/genética , Fitomejoramiento , Almidón , Amilosa , Proteínas de Plantas/genética
8.
Proc Natl Acad Sci U S A ; 120(36): e2304851120, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37639608

RESUMEN

Memory formation and forgetting unnecessary memory must be balanced for adaptive animal behavior. While cyclic AMP (cAMP) signaling via dopamine neurons induces memory formation, here we report that cyclic guanine monophosphate (cGMP) signaling via dopamine neurons launches forgetting of unconsolidated memory in Drosophila. Genetic screening and proteomic analyses showed that neural activation induces the complex formation of a histone H3K9 demethylase, Kdm4B, and a GMP synthetase, Bur, which is necessary and sufficient for forgetting unconsolidated memory. Kdm4B/Bur is activated by phosphorylation through NO-dependent cGMP signaling via dopamine neurons, inducing gene expression, including kek2 encoding a presynaptic protein. Accordingly, Kdm4B/Bur activation induced presynaptic changes. Our data demonstrate a link between cGMP signaling and synapses via gene expression in forgetting, suggesting that the opposing functions of memory are orchestrated by distinct signaling via dopamine neurons, which affects synaptic integrity and thus balances animal behavior.


Asunto(s)
Neuronas Dopaminérgicas , Proteómica , Animales , Sistemas de Mensajero Secundario , Transducción de Señal , Memoria , Drosophila , Guanina , Histona Demetilasas
9.
Proc Natl Acad Sci U S A ; 120(1): e2208623119, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36584300

RESUMEN

Haploinsufficiency for SOX9, the master chondrogenesis transcription factor, can underlie campomelic dysplasia (CD), an autosomal dominant skeletal malformation syndrome, because heterozygous Sox9 null mice recapitulate the bent limb (campomelia) and some other phenotypes associated with CD. However, in vitro cell assays suggest haploinsufficiency may not apply for certain mutations, notably those that truncate the protein, but in these cases in vivo evidence is lacking and underlying mechanisms are unknown. Here, using conditional mouse mutants, we compared the impact of a heterozygous Sox9 null mutation (Sox9+/-) with the Sox9+/Y440X CD mutation that truncates the C-terminal transactivation domain but spares the DNA-binding domain. While some Sox9+/Y440X mice survived, all Sox9+/- mice died perinatally. However, the skeletal defects were more severe and IHH signaling in developing limb cartilage was significantly enhanced in Sox9+/Y440X compared with Sox9+/-. Activating Sox9Y440X specifically in the chondrocyte-osteoblast lineage caused milder campomelia, and revealed cell- and noncell autonomous mechanisms acting on chondrocyte differentiation and osteogenesis in the perichondrium. Transcriptome analyses of developing Sox9+/Y440X limbs revealed dysregulated expression of genes for the extracellular matrix, as well as changes consistent with aberrant WNT and HH signaling. SOX9Y440X failed to interact with ß-catenin and was unable to suppress transactivation of Ihh in cell-based assays. We propose enhanced HH signaling in the adjacent perichondrium induces asymmetrically localized excessive perichondrial osteogenesis resulting in campomelia. Our study implicates combined haploinsufficiency/hypomorphic and dominant-negative actions of SOX9Y440X, cell-autonomous and noncell autonomous mechanisms, and dysregulated WNT and HH signaling, as the cause of human campomelia.


Asunto(s)
Erizos , Vía de Señalización Wnt , Humanos , Ratones , Animales , Erizos/metabolismo , Regulación de la Expresión Génica , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Diferenciación Celular/genética , Proteínas/metabolismo , Condrocitos/metabolismo
10.
Am J Pathol ; 194(6): 1078-1089, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38417697

RESUMEN

Ferroptosis is a new form of cell death characterized by iron-dependent lipid peroxidation. Whether ferroptosis is involved in retinal microvascular dysfunction under diabetic condition is not known. Herein, the expression of ferroptosis-related genes in patients with proliferative diabetic retinopathy and in diabetic mice was determined with quantitative RT-PCR. Reactive oxygen species, iron content, lipid peroxidation products, and ferroptosis-associated proteins in the cultured human retinal microvascular endothelial cells (HRMECs) and in the retina of diabetic mice were examined. The association of ferroptosis with the functions of endothelial cells in vitro was evaluated. After administration of ferroptosis-specific inhibitor, Fer-1, the retinal microvasculature in diabetic mice was assessed. Characteristic changes of ferroptosis-associated markers, including glutathione peroxidase 4, ferritin heavy chain 1, long-chain acyl-CoA synthetase 4, transferrin receptor protein 1, and cyclooxygenase-2, were detected in the retinal fibrovascular membrane of patients with proliferative diabetic retinopathy, cultured HRMECs, and the retina of diabetic mice. Elevated levels of reactive oxygen species, lipid peroxidation, and iron content were found in the retina of diabetic mice and in cultured HRMECs. Ferroptosis was found to be associated with HRMEC dysfunction under high-glucose condition. Inhibition of ferroptosis with specific inhibitor Fer-1 in diabetic mice significantly reduced the severity of retinal microvasculopathy. Ferroptosis contributes to microvascular dysfunction in diabetic retinopathy, and inhibition of ferroptosis might be a promising strategy for the therapy of early-stage diabetic retinopathy.


Asunto(s)
Retinopatía Diabética , Ferroptosis , Especies Reactivas de Oxígeno , Retinopatía Diabética/patología , Retinopatía Diabética/metabolismo , Animales , Humanos , Ratones , Masculino , Especies Reactivas de Oxígeno/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/patología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Peroxidación de Lípido , Ratones Endogámicos C57BL , Microvasos/patología , Microvasos/metabolismo , Hierro/metabolismo , Vasos Retinianos/metabolismo , Vasos Retinianos/patología
11.
J Immunol ; 211(6): 981-993, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37493438

RESUMEN

Current vaccine efforts to combat SARS-CoV-2 are focused on the whole spike protein administered as mRNA, viral vector, or protein subunit. However, the SARS-CoV-2 receptor-binding domain (RBD) is the immunodominant portion of the spike protein, accounting for 90% of serum neutralizing activity. In this study, we constructed several versions of RBD and together with aluminum hydroxide or DDA (dimethyldioctadecylammonium bromide)/TDB (d-(+)-trehalose 6,6'-dibehenate) adjuvant evaluated immunogenicity in mice. We generated human angiotensin-converting enzyme 2 knock-in mice to evaluate vaccine efficacy in vivo following viral challenge. We found that 1) subdomain (SD)1 was essential for the RBD to elicit maximal immunogenicity; 2) RBDSD1 produced in mammalian HEK cells elicited better immunogenicity than did protein produced in insect or yeast cells; 3) RBDSD1 combined with the CD4 Th1 adjuvant DDA/TDB produced higher neutralizing Ab responses and stronger CD4 T cell responses than did aluminum hydroxide; 4) addition of monomeric human Fc receptor to RBDSD1 (RBDSD1Fc) significantly enhanced immunogenicity and neutralizing Ab titers; 5) the Beta version of RBDSD1Fc provided a broad range of cross-neutralization to multiple antigenic variants of concern, including Omicron; and 6) the Beta version of RBDSD1Fc with DDA/TDB provided complete protection against virus challenge in the knock-in mouse model. Thus, we have identified an optimized RBD-based subunit vaccine suitable for clinical trials.


Asunto(s)
COVID-19 , Vacunas Virales , Humanos , Animales , Ratones , SARS-CoV-2 , Vacunas contra la COVID-19 , Hidróxido de Aluminio , Glicoproteína de la Espiga del Coronavirus , Vacunas de Subunidad , Anticuerpos Antivirales , Anticuerpos Neutralizantes , Mamíferos
12.
Cell Mol Life Sci ; 81(1): 158, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38556571

RESUMEN

Mutations in cysteine and glycine-rich protein 3 (CSRP3)/muscle LIM protein (MLP), a key regulator of striated muscle function, have been linked to hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) in patients. However, the roles of CSRP3 in heart development and regeneration are not completely understood. In this study, we characterized a novel zebrafish gene-trap line, gSAIzGFFM218A, which harbors an insertion in the csrp3 genomic locus, heterozygous fish served as a csrp3 expression reporter line and homozygous fish served as a csrp3 mutant line. We discovered that csrp3 is specifically expressed in larval ventricular cardiomyocytes (CMs) and that csrp3 deficiency leads to excessive trabeculation, a common feature of CSRP3-related HCM and DCM. We further revealed that csrp3 expression increased in response to different cardiac injuries and was regulated by several signaling pathways vital for heart regeneration. Csrp3 deficiency impeded zebrafish heart regeneration by impairing CM dedifferentiation, hindering sarcomere reassembly, and reducing CM proliferation while aggravating apoptosis. Csrp3 overexpression promoted CM proliferation after injury and ameliorated the impairment of ventricle regeneration caused by pharmacological inhibition of multiple signaling pathways. Our study highlights the critical role of Csrp3 in both zebrafish heart development and regeneration, and provides a valuable animal model for further functional exploration that will shed light on the molecular pathogenesis of CSRP3-related human cardiac diseases.


Asunto(s)
Cardiomiopatía Hipertrófica , Proteínas con Dominio LIM , Pez Cebra , Animales , Humanos , Pez Cebra/genética , Pez Cebra/metabolismo , Cisteína/genética , Cisteína/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/metabolismo , Miocitos Cardíacos/metabolismo
13.
Nano Lett ; 24(38): 11823-11830, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39235125

RESUMEN

To address food security challenges and climate change, the polyploid wild rice Oryza alta has been explored as a potential crop, although it suffers from seed shattering. We employed mesoporous silica nanoparticles (MSNs) to deliver small interfering RNAs (siRNAs) for targeted gene silencing. Foliar spraying of MSN-siRNA complexes effectively delivered siRNA, resulting in up to 70% gene silencing of the PDS gene and 75% silencing of the transgenic Ruby gene. Additionally, MSN-siRNAs were infiltrated into the panicles of O. alta to target four seed shattering major genes every other day for 2 weeks until heading outdoors. This method silenced all four shattering genes ranging from 10.7% to 49.4% and significantly reduced the formation of the abscission layer between rice grains and pedicels, which enhanced pedicel tensile strength. Our MSN-siRNA system provides a flexible, nonpermanent approach to modifying crop traits, offering a promising tool for sustainable agricultural practices.


Asunto(s)
Nanopartículas , Oryza , ARN Interferente Pequeño , Semillas , Dióxido de Silicio , Oryza/genética , Dióxido de Silicio/química , Nanopartículas/química , ARN Interferente Pequeño/química , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Semillas/química , Semillas/genética , Porosidad , Silenciador del Gen , Plantas Modificadas Genéticamente/genética
14.
Nano Lett ; 24(37): 11482-11489, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39158148

RESUMEN

A novel antiferroelectric material, PbSnO3 (PSO), was introduced into a resistive random access memory (RRAM) to reveal its resistive switching (RS) properties. It exhibits outstanding electrical performance with a large memory window (>104), narrow switching voltage distribution (±2 V), and low power consumption. Using high-resolution transmission electron microscopy, we observed the antiferroelectric properties and remanent polarization of the PSO thin films. The in-plane shear strains in the monoclinic PSO layer are attributed to oxygen octahedral tilts, resulting in misfit dislocations and grain boundaries at the PSO/SRO interface. Furthermore, the incoherent grain boundaries between the orthorhombic and monoclinic phases are assumed to be the primary paths of Ag+ filaments. Therefore, the RS behavior is primarily dominated by antiferroelectric polarization and defect mechanisms for the PSO structures. The RS behavior of antiferroelectric heterostructures controlled by switching spontaneous polarization and strain, defects, and surface chemistry reactions can facilitate the development of new antiferroelectric device systems.

15.
J Infect Dis ; 230(3): 569-577, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-38394609

RESUMEN

BACKGROUND: Chlamydia trachomatis testing and treatment strategies have not decreased infection rates, justifying need for a chlamydia vaccine. A murine study showed that a vaccine consisting of major outer membrane protein (MOMP) and polymorphic membrane proteins (Pmps) E, F, G, and H elicited protective immunity; studies on human cellular immune responses to Pmps are sparse. METHODS: Interferon gamma (IFN-γ) responses to these 5 proteins were measured by ELISPOT in peripheral blood mononuclear cells from women returning for treatment of a positive chlamydia test. Responses were compared in those with spontaneous chlamydia clearance versus persisting infection at baseline and no reinfection versus reinfection at a 3-month follow-up visit. RESULTS: IFN-γ response to 1 or more proteins was detected in 39% at baseline and 51.5% at follow-up, most often to PmpE and MOMP. IFN-γ responses to MOMP were detected less often at follow-up versus baseline in women with reinfection, but were maintained in those without reinfection. Women with spontaneous clearance had a higher magnitude of IFN-γ response to PmpE and MOMP. CONCLUSIONS: IFN-γ responses to these 5 C. trachomatis vaccine candidate proteins were heterogenous and primarily directed against MOMP and PmpE. Spontaneous chlamydia clearance and absence of reinfection may be clinical correlates of protection.


Asunto(s)
Vacunas Bacterianas , Infecciones por Chlamydia , Chlamydia trachomatis , Interferón gamma , Leucocitos Mononucleares , Humanos , Femenino , Chlamydia trachomatis/inmunología , Infecciones por Chlamydia/inmunología , Infecciones por Chlamydia/prevención & control , Interferón gamma/metabolismo , Vacunas Bacterianas/inmunología , Adulto Joven , Adulto , Leucocitos Mononucleares/inmunología , Adolescente , Proteínas Bacterianas/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Reinfección/inmunología , Reinfección/prevención & control , Ensayo de Immunospot Ligado a Enzimas
16.
Circulation ; 148(23): 1887-1906, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-37905452

RESUMEN

BACKGROUND: The importance of mitochondria in normal heart function are well recognized and recent studies have implicated changes in mitochondrial metabolism with some forms of heart disease. Previous studies demonstrated that knockdown of the mitochondrial ribosomal protein S5 (MRPS5) by small interfering RNA (siRNA) inhibits mitochondrial translation and thereby causes a mitonuclear protein imbalance. Therefore, we decided to examine the effects of MRPS5 loss and the role of these processes on cardiomyocyte proliferation. METHODS: We deleted a single allele of MRPS5 in mice and used left anterior descending coronary artery ligation surgery to induce myocardial damage in these animals. We examined cardiomyocyte proliferation and cardiac regeneration both in vivo and in vitro. Doxycycline treatment was used to inhibit protein translation. Heart function in mice was assessed by echocardiography. Quantitative real-time polymerase chain reaction and RNA sequencing were used to assess changes in transcription and chromatin immunoprecipitation (ChIP) and BioChIP were used to assess chromatin effects. Protein levels were assessed by Western blotting and cell proliferation or death by histology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays. Adeno-associated virus was used to overexpress genes. The luciferase reporter assay was used to assess promoter activity. Mitochondrial oxygen consumption rate, ATP levels, and reactive oxygen species were also analyzed. RESULTS: We determined that deletion of a single allele of MRPS5 in mice results in elevated cardiomyocyte proliferation and cardiac regeneration; this observation correlates with improved cardiac function after induction of myocardial infarction. We identified ATF4 (activating transcription factor 4) as a key regulator of the mitochondrial stress response in cardiomyocytes from Mrps5+/- mice; furthermore, ATF4 regulates Knl1 (kinetochore scaffold 1) leading to an increase in cytokinesis during cardiomyocyte proliferation. The increased cardiomyocyte proliferation observed in Mrps5+/- mice was attenuated when one allele of Atf4 was deleted genetically (Mrps5+/-/Atf4+/-), resulting in the loss in the capacity for cardiac regeneration. Either MRPS5 inhibition (or as we also demonstrate, doxycycline treatment) activate a conserved regulatory mechanism that increases the proliferation of human induced pluripotent stem cell-derived cardiomyocytes. CONCLUSIONS: These data highlight a critical role for MRPS5/ATF4 in cardiomyocytes and an exciting new avenue of study for therapies to treat myocardial injury.


Asunto(s)
Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Humanos , Ratones , Animales , Miocitos Cardíacos/metabolismo , Doxiciclina , Células Cultivadas , Células Madre Pluripotentes Inducidas/metabolismo , ARN Interferente Pequeño/metabolismo , Biosíntesis de Proteínas , Proliferación Celular , Regeneración , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo
17.
BMC Genomics ; 25(1): 228, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429694

RESUMEN

BACKGROUND: Late embryogenesis abundant (LEA) proteins play important roles in plant growth and development, as well as stresses responsiveness. Nowadays, it has been found that LEAs also have function in fruit ripening. However, the comprehensive analysis on a genome-wide basis of LEA family remains limited, and the role of LEA in fruit ripening has not been fully explored yet, especially in strawberry, an economic important plant and ideal material for studying fruit ripening. RESULTS: In this study, a total of 266 putative LEA proteins were identified and characterized in strawberry genome. Subcellular localization prediction indicated that they were mostly localized in chloroplast, cytoplasm and nucleus. Duplication events detection revealed that whole genome duplication or segmental was the main driver for the expansion of LEA family in strawberry. The phylogenetic analysis suggested that FaLEAs were classified into eight groups, among which, LEA2 was the largest subgroup with 179 members, followed by LEA3, dehydrin (DHN), LEA4 and SMP (seed maturation protein). The LEA1 and DHN groups were speculated to play dominant roles in strawberry fruit development and ripening, according to their larger proportion of members detected as differentially expressed genes during such process. Notably, the expression of FaLEA167 belonging to LEA1 group was altered by strawberry maturation, and inhibited by overexpression of negative regulators of ripening (a cytosolic/plastid glyceraldehyde-3-phosphate dehydrogenase, FaGAPC2 and a cytosolic pyruvate kinase, FaPKc2.2). Subsequently, overexpression of FaLEA167 significantly increased the percentage of fruit at green stage, while reduced the full red fruit proportion. In consistent, the anthocyanins content and the fruit skin color variable reflecting a range from greenness to redness (a* value) were significantly reduced. Whereas, FaLEA167 overexpression apparently up-regulated citric acid, soluble protein and malondialdehyde content, but had no obvious effects on total soluble solids, sugar, flavonoids, phenolics content and antioxidant capacity. CONCLUSIONS: These findings not only provided basic information of FaLEA family for further functional research, but also revealed the involvement of FaLEA167 in negatively regulating strawberry fruit ripening, giving new insights into understanding of FaLEA functions.


Asunto(s)
Fragaria , Antocianinas/metabolismo , Frutas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
18.
Mol Cancer ; 23(1): 124, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849840

RESUMEN

BACKGROUND: Intestinal metaplasia (IM) is classified into complete intestinal metaplasia (CIM) and incomplete intestinal metaplasia (IIM). Patients diagnosed with IIM face an elevated susceptibility to the development of gastric cancer, underscoring the critical need for early screening measures. In addition to the complexities associated with diagnosis, the exact mechanisms driving the progression of gastric cancer in IIM patients remain poorly understood. OLFM4 is overexpressed in several types of tumors, including colorectal, gastric, pancreatic, and ovarian cancers, and its expression has been associated with tumor progression. METHODS: In this study, we used pathological sections from two clinical centers, biopsies of IM tissues, precancerous lesions of gastric cancer (PLGC) cell models, animal models, and organoids to explore the role of OLFM4 in IIM. RESULTS: Our results show that OLFM4 expression is highly increased in IIM, with superior diagnostic accuracy of IIM when compared to CDX2 and MUC2. OLFM4, along with MYH9, was overexpressed in IM organoids and PLGC animal models. Furthermore, OLFM4, in combination with Myosin heavy chain 9 (MYH9), accelerated the ubiquitination of GSK3ß and resulted in increased ß-catenin levels through the Wnt signaling pathway, promoting the proliferation and invasion abilities of PLGC cells. CONCLUSIONS: OLFM4 represents a novel biomarker for IIM and could be utilized as an important auxiliary means to delimit the key population for early gastric cancer screening. Finally, our study identifies cell signaling pathways involved in the progression of IM.


Asunto(s)
Progresión de la Enfermedad , Glucógeno Sintasa Quinasa 3 beta , Metaplasia , Cadenas Pesadas de Miosina , beta Catenina , Humanos , Metaplasia/metabolismo , Metaplasia/patología , Metaplasia/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Animales , beta Catenina/metabolismo , beta Catenina/genética , Ratones , Cadenas Pesadas de Miosina/metabolismo , Cadenas Pesadas de Miosina/genética , Neoplasias Gástricas/patología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Femenino , Vía de Señalización Wnt , Proliferación Celular , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Modelos Animales de Enfermedad , Masculino , Organoides/metabolismo , Organoides/patología
19.
PLoS Med ; 21(5): e1004389, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728364

RESUMEN

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorrectales , Fluorouracilo , Leucovorina , Neoplasias Hepáticas , Compuestos Organoplatinos , Proteínas Proto-Oncogénicas B-raf , Humanos , Cetuximab/administración & dosificación , Cetuximab/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Masculino , Persona de Mediana Edad , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/tratamiento farmacológico , Femenino , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Leucovorina/uso terapéutico , Leucovorina/administración & dosificación , Fluorouracilo/uso terapéutico , Fluorouracilo/administración & dosificación , Compuestos Organoplatinos/uso terapéutico , Compuestos Organoplatinos/administración & dosificación , Proteínas Proto-Oncogénicas B-raf/genética , Anciano , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/administración & dosificación , Resultado del Tratamiento , Proteínas ras/genética
20.
Br J Cancer ; 131(4): 692-701, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38918556

RESUMEN

BACKGROUND: This study aims to develop a stacking model for accurately predicting axillary lymph node (ALN) response to neoadjuvant chemotherapy (NAC) using longitudinal MRI in breast cancer. METHODS: We included patients with node-positive breast cancer who received NAC following surgery from January 2012 to June 2022. We collected MRIs before and after NAC, and extracted radiomics features from the tumour, peritumour, and ALN regions. The Mann-Whitney U test, least absolute shrinkage and selection operator, and Boruta algorithm were used to select features. We utilised machine learning techniques to develop three single-modality models and a stacking model for predicting ALN response to NAC. RESULTS: This study consisted of a training cohort (n = 277), three external validation cohorts (n = 313, 164, and 318), and a prospective cohort (n = 81). Among the 1153 patients, 60.62% achieved ypN0. The stacking model achieved excellent AUCs of 0.926, 0.874, and 0.862 in the training, external validation, and prospective cohort, respectively. It also showed lower false-negative rates (FNRs) compared to radiologists, with rates of 14.40%, 20.85%, and 18.18% (radiologists: 40.80%, 50.49%, and 63.64%) in three cohorts. Additionally, there was a significant difference in disease-free survival between high-risk and low-risk groups (p < 0.05). CONCLUSIONS: The stacking model can accurately predict ALN status after NAC in breast cancer, showing a lower false-negative rate than radiologists. TRIAL REGISTRATION NUMBER: The clinical trial numbers were NCT03154749 and NCT04858529.


Asunto(s)
Inteligencia Artificial , Axila , Neoplasias de la Mama , Imagen por Resonancia Magnética , Terapia Neoadyuvante , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Persona de Mediana Edad , Adulto , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Ganglios Linfáticos/patología , Ganglios Linfáticos/diagnóstico por imagen , Anciano , Metástasis Linfática , Aprendizaje Automático , Quimioterapia Adyuvante
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