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1.
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
2.
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
3.
J Med Genet ; 61(7): 652-660, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38508705

RESUMEN

BACKGROUND: The ZFHX3 gene plays vital roles in embryonic development, cell proliferation, neuronal differentiation and neuronal death. This study aims to explore the relationship between ZFHX3 variants and epilepsy. METHODS: Whole-exome sequencing was performed in a cohort of 378 patients with partial (focal) epilepsy. A Drosophila Zfh2 knockdown model was used to validate the association between ZFHX3 and epilepsy. RESULTS: Compound heterozygous ZFHX3 variants were identified in eight unrelated cases. The burden of ZFHX3 variants was significantly higher in the case cohort, shown by multiple/specific statistical analyses. In Zfh2 knockdown flies, the incidence and duration of seizure-like behaviour were significantly greater than those in the controls. The Zfh2 knockdown flies exhibited more firing in excitatory neurons. All patients presented partial seizures. The five patients with variants in the C-terminus/N-terminus presented mild partial epilepsy. The other three patients included one who experienced frequent non-convulsive status epilepticus and two who had early spasms. These three patients had also neurodevelopmental abnormalities and were diagnosed as developmental epileptic encephalopathy (DEE), but achieved seizure-free after antiepileptic-drug treatment without adrenocorticotropic-hormone/steroids. The analyses of temporal expression (genetic dependent stages) indicated that ZFHX3 orthologous were highly expressed in the embryonic stage and decreased dramatically after birth. CONCLUSION: ZFHX3 is a novel causative gene of childhood partial epilepsy and DEE. The patients of infantile spasms achieved seizure-free after treatment without adrenocorticotropic-hormone/steroids implies a significance of genetic diagnosis in precise treatment. The genetic dependent stage provided an insight into the underlying mechanism of the evolutional course of illness.


Asunto(s)
Epilepsias Parciales , Proteínas de Homeodominio , Espasmos Infantiles , Animales , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Epilepsias Parciales/genética , Epilepsias Parciales/tratamiento farmacológico , Secuenciación del Exoma , Predisposición Genética a la Enfermedad , Proteínas de Homeodominio/genética , Mutación , Espasmos Infantiles/genética , Drosophila
4.
J Proteome Res ; 23(5): 1689-1701, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38565891

RESUMEN

Cyanobacteria are the oldest prokaryotic photoautotrophic microorganisms and have evolved complicated post-translational modification (PTM) machinery to respond to environmental stress. Lysine 2-hydroxyisobutyrylation (Khib) is a newly identified PTM that is reported to play important roles in diverse biological processes, however, its distribution and function in cyanobacteria have not been reported. Here, we performed the first systematic studies of Khib in a model cyanobacterium Synechococcus sp. strain PCC 7002 (Syn7002) using peptide prefractionation, pan-Khib antibody enrichment, and high-accuracy mass spectrometry (MS) analysis. A total of 1875 high-confidence Khib sites on 618 proteins were identified, and a large proportion of Khib sites are present on proteins in the cellular metabolism, protein synthesis, and photosynthesis pathways. Using site-directed mutagenesis and functional studies, we showed that Khib of glutaredoxin (Grx) affects the efficiency of the PS II reaction center and H2O2 resistance in Syn7002. Together, this study provides novel insights into the functions of Khib in cyanobacteria and suggests that reversible Khib may influence the stress response and photosynthesis in both cyanobacteria and plants.


Asunto(s)
Lisina , Procesamiento Proteico-Postraduccional , Synechococcus , Lisina/metabolismo , Synechococcus/metabolismo , Synechococcus/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Peróxido de Hidrógeno/metabolismo , Glutarredoxinas/metabolismo , Glutarredoxinas/genética , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/genética , Mutagénesis Sitio-Dirigida , Fotosíntesis , Cianobacterias/metabolismo , Cianobacterias/genética , Espectrometría de Masas
5.
J Proteome Res ; 23(4): 1174-1187, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38427982

RESUMEN

Protein homeostasis is essential for cyanobacteria to maintain proper cellular function under adverse and fluctuating conditions. The AAA+ superfamily of proteolytic complexes in cyanobacteria plays a critical role in this process, including ClpXP, which comprises a hexameric ATPase ClpX and a tetradecameric peptidase ClpP. Despite the physiological effects of ClpX on growth and photosynthesis, its potential substrates and underlying mechanisms in cyanobacteria remain unknown. In this study, we employed a streptavidin-biotin affinity pull-down assay coupled with label-free proteome quantitation to analyze the interactome of ClpX in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis). We identified 503 proteins as potential ClpX-binding targets, many of which had novel interactions. These ClpX-binding targets were found to be involved in various biological processes, with particular enrichment in metabolic processes and photosynthesis. Using protein-protein docking, GST pull-down, and biolayer interferometry assays, we confirmed the direct association of ClpX with the photosynthetic proteins, ferredoxin-NADP+ oxidoreductase (FNR) and phycocyanin subunit (CpcA). Subsequent functional investigations revealed that ClpX participates in the maintenance of FNR homeostasis and functionality in Synechocystis grown under different light conditions. Overall, our study provides a comprehensive understanding of the extensive functions regulated by ClpX in cyanobacteria to maintain protein homeostasis and adapt to environmental challenges.


Asunto(s)
Fotosíntesis , Synechocystis , Fotosíntesis/genética , Synechocystis/genética , Synechocystis/metabolismo , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Ficocianina/metabolismo
6.
Apoptosis ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38498249

RESUMEN

Chimeric antigen receptor (CAR) T-cell therapy is highly effective for treating blood cancers such as B-cell malignancies, however, its effectiveness as an approach to treat solid tumors remains to be further explored. Here, we focused on the development of CAR-T cell therapies targeting tropomyosin-related kinase receptor B (TRKB), a highly expressed protein that is significantly associated with tumor progression, malignancy, and drug resistance in multiple forms of aggressive solid tumors. To achieve this, we screened brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NTF4) ligand-based CAR-T cells for their efficiency in targeting the TRKB receptor in the context of solid tumors, particularly hepatocellular carcinoma and pancreatic cancer. We demonstrated that TRKB is overexpressed not only in hepatocellular carcinoma and pancreatic carcinoma cell lines but also in cancer stem-like cells (CSCs). Notably, BDNF-CAR T and NTF4-CAR T cells could not only effectively target and kill TRKB-expressing pan-cancer cell lines in a dose-dependent manner but also effectively kill CSCs. We also performed in vivo studies to show that NTF4-CAR T cells have a better potential to inhibit the tumor growth of hepatocellular carcinoma xenografts in mice, compared with BDNF-CAR T cells. Taken together, our findings suggest that CAR-T targeting TRKB may be a promising approach for developing novel therapies to treat solid cancers.

7.
Plant Physiol ; 192(1): 426-441, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36805986

RESUMEN

Glycerolipids are the most abundant lipids in microalgae, and glycerol-3-phosphate:acyl-CoA acyltransferase (GPAT) plays an important role in their biosynthesis. However, the biochemical and biological functions of algal GPAT remain poorly characterized. Here, we characterized the endoplasmic reticulum (ER)-associated GPAT of the model unicellular green alga Chlamydomonas reinhardtii (CrGPATer). Enzymatic assays indicated that CrGPATer is an sn-1 acyltransferase using a variety of acyl-CoAs as the acyl donor. Subcellular localization revealed that CrGPATer was associated with ER membranes and lipid droplets. We constructed overexpression (OE) and knockdown (KD) transgenic C. reinhardtii lines to investigate the in vivo function of CrGPATer. Lipidomic analysis indicated that CrGPATer OE enhanced the cellular content of galactolipids, especially monogalactosyldiacylglycerol, under nitrogen deficiency stress. Correspondingly, CrGPATer KD lines contained lower contents of galactolipids than the control. Feeding experiments with labeled phosphatidic acid revealed that the intermediate of the eukaryotic Kennedy pathway could be used for galactolipid biosynthesis in the chloroplasts. These results provided multiple lines of evidence that the eukaryotic Kennedy pathway mediated by CrGPATer may be involved in galactolipid biosynthesis in C. reinhardtii. OE of CrGPATer significantly increased the content of triacylglycerol and the yield of biomass. Moreover, the content and yield of 1, 3-olein-2-palmitin, a high-value lipid that can be used as an alternative for human milk fat in infant formula, were significantly enhanced in the OE transgenic lines. Taken together, this study provided insights into the biochemical and biological functions of CrGPATer and its potential as a genetic engineering target in functional lipid manufacturing.


Asunto(s)
Galactolípidos , Microalgas , Humanos , Aciltransferasas/metabolismo , Galactolípidos/metabolismo , Glicerol/metabolismo , Glicerol-3-Fosfato O-Aciltransferasa/genética , Glicerol-3-Fosfato O-Aciltransferasa/química , Glicerol-3-Fosfato O-Aciltransferasa/metabolismo , Microalgas/genética , Microalgas/metabolismo , Fosfatos/metabolismo , Plantas/metabolismo , Triglicéridos/metabolismo , Metabolismo de los Lípidos
8.
BMC Cardiovasc Disord ; 24(1): 29, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172720

RESUMEN

BACKGROUND: Patients with nonischemic dilated cardiomyopathy (NIDCM) are prone to arrhythmias, and the cause of mortality in these patients is either end-organ dysfunction due to pump failure or malignant arrhythmia-related death. However, the identification of patients with NIDCM at risk of malignant ventricular arrhythmias (VAs) is challenging in clinical practice. The aim of this study was to evaluate whether cardiovascular magnetic resonance feature tracking (CMR-FT) could help in the identification of patients with NIDCM at risk of malignant VAs. METHODS: A total of 263 NIDCM patients who underwent CMR, 24-hour Holter electrocardiography (ECG) and inpatient ECG were retrospectively evaluated. The patients with NIDCM were allocated to two subgroups: NIDCM with VAs and NIDCM without VAs. From CMR-FT, the global peak radial strain (GPRS), global longitudinal strain (GPLS), and global peak circumferential strain (GPCS) were calculated from the left ventricle (LV) model. We investigated the possible predictors of NIDCM combined with VAs by univariate and multivariate logistic regression analyses. RESULTS: The percent LGE (15.51 ± 3.30 vs. 9.62 ± 2.18, P < 0.001) was higher in NIDCM patients with VAs than in NIDCM patients without VAs. Furthermore, the NIDCM patients complicated with VAs had significantly lower GPCS than the NIDCM patients without VAs (- 5.38 (- 7.50, - 4.22) vs.-9.22 (- 10.73, - 8.19), P < 0.01). Subgroup analysis based on LGE negativity showed that NIDCM patients complicated with VAs had significantly lower GPRS, GPCS, and GPLS than NIDCM patients without VAs (P < 0.05 for all). Multivariate analysis showed that both GPCS and %LGE were independent predictors of NIDCM combined with VAs. CONCLUSIONS: CMR global strain can be used to identify NIDCM patients complicated with VAs early, specifically when LGE is not present. GPCS < - 13.19% and %LGE > 10.37% are independent predictors of NIDCM combined with VAs.


Asunto(s)
Cardiomiopatía Dilatada , Humanos , Cardiomiopatía Dilatada/complicaciones , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/patología , Miocardio/patología , Estudios Retrospectivos , Imagen por Resonancia Cinemagnética , Pronóstico , Arritmias Cardíacas/etiología , Arritmias Cardíacas/complicaciones , Espectroscopía de Resonancia Magnética , Medios de Contraste , Valor Predictivo de las Pruebas
9.
Qual Life Res ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008142

RESUMEN

OBJECTIVE: This study was to evaluate measurement properties of the Chinese version of the Brief Inventory of Perceived Stress (BIPS-C) and confirm possible solutions for measuring the constructs underlying perceived stress. METHODS: A total of 1356 community residents enrolled and were randomly split into two halves. The first half was used to explore the underlying constructs of the BIPS-C by exploratory graph analysis (EGA) and the second half was used to compare and confirm the constructs by confirmatory factor analysis (CFA). RESULTS: The EGA identified a one-factor model of the BIPS-C with an accuracy of 99.3%. One-factor, three-factor, second-order, and bifactor models were compared by CFAs. The bifactor model with one general and three specific factors was found to be the most adequate [comparative fit index (CFI) = 0.990; Tucker-Lewis index (TLI) = 0.979; root mean square error of approximation (RMSEA) = 0.058] and was superior to the other models. The related bifactor indices showed a stronger existence of the general factor. The bifactor model of the BIPS-C also showed adequate internal consistency with McDonald's omega and omega subscales ranging from moderate to strong (0.677-0.869). CONCLUSION: The BIPS-C demonstrates sufficient measurement properties for assessing general perceived stress.

10.
BMC Geriatr ; 24(1): 523, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886643

RESUMEN

PURPOSE: Smoking is a risk factor for sarcopenia. Nevertheless, few studies analyzed the independent effects of various smoking dimensions (duration, intensity, cumulative dose) on sarcopenia risk. This is a cross-sectional study based on an older population in Zhejiang Province to determine which smoking dimensions are mainly important for sarcopenia risk and to explore the dose-response relationship between them. METHODS: Our study included 783 patients with sarcopenia and 4918 non-sarcopenic individuals. Logistic regression and restricted cubic with logistic regression (for nonlinear dose effects) were used to obtain odds ratios (ORs) and 95% confidence intervals as well as restricted cubic splines (RCS) curves. RESULTS: Compared with never-smokers, current smokers had an increased risk of sarcopenia (OR = 1.786; 95% CI 1.387-2.301) after adjusting for confounders such as age, sex, education, alcohol consumption, disease history, etc. There was no significant association between smoking intensity and sarcopenia after more than 20 cigarettes per day (OR = 1.484; 95% CI 0.886-2.487), whereas the risk of sarcopenia increased significantly with increasing duration of smoking after more than 40 years (OR = 1.733; 95% CI 1.214-2.473). Meanwhile, there was a significant non-linear dose-response relationship between smoking duration or intensity and the risk of sarcopenia. However, the risk of sarcopenia increased linearly with the number of pack-years of smoking, which is not a significant nonlinear dose-response relationship. CONCLUSIONS: This study indicated the association between smoking and sarcopenia. Both smoking duration and cumulative dose were significantly and positively associated with sarcopenia. These findings reflect the important role of the number of years of smoking in increasing the risk of sarcopenia and provide scientific evidence that different smoking dimensions may influence the risk of the sarcopenia.


Asunto(s)
Fumar Cigarrillos , Sarcopenia , Humanos , Sarcopenia/epidemiología , Estudios Transversales , Masculino , Femenino , Anciano , China/epidemiología , Fumar Cigarrillos/epidemiología , Fumar Cigarrillos/efectos adversos , Persona de Mediana Edad , Factores de Riesgo , Anciano de 80 o más Años
11.
Breast Cancer Res ; 25(1): 22, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36829181

RESUMEN

BACKGROUND: Breast cancer is the major cause of death in females globally. Chemokine-like factor like MARVEL transmembrane domain containing 7 (CMTM7) is reported as a tumor suppressor and is involved in epidermal growth factor receptor degradation and PI3K/AKT signaling in previous studies. However, other molecular mechanisms of CMTM7 remain unclear. METHODS: The expression level of CMTM7 in breast cancer cells and tissues was detected by qRT-PCR and western blot, and the methylation of CMTM7 promoter was detected by BSP sequencing. The effect of CMTM7 was verified both in vitro and in vivo, including MTT, colony formation, EdU assay, transwell assay and wound healing assay. The interaction between CMTM7 and CTNNA1 was investigated by co-IP assay. The regulation of miR-182-5p on CMTM7 and TCF3 on miR-182-5p was detected by luciferase reporter assay and ChIP analysis. RESULTS: This study detected the hypermethylation levels of the CMTM7 promoter region in breast cancer tissues and cell lines. CMTM7 was performed as a tumor suppressor both in vitro and in vivo. Furthermore, CMTM7 was a direct miR-182-5p target. Besides, we found that CMTM7 could interact with Catenin Alpha 1 (CTNNA1) and regulate Wnt/ß-catenin signaling. Finally, transcription factor 3 (TCF3) can regulate miR-182-5p. We identified a feedback loop with the composition of miR-182-5p, CMTM7, CTNNA1, CTNNB1 (ß-catenin), and TCF3, which play essential roles in breast cancer progression. CONCLUSION: These findings reveal the emerging character of CMTM7 in Wnt/ß-catenin signaling and bring new sights of gene interaction. CMTM7 and other elements in the feedback loop may serve as emerging targets for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Femenino , Humanos , MicroARNs/genética , Neoplasias de la Mama/genética , beta Catenina/genética , beta Catenina/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Línea Celular Tumoral , Vía de Señalización Wnt/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Quimiocinas/metabolismo , Proteínas con Dominio MARVEL/genética , Proteínas con Dominio MARVEL/metabolismo
12.
Mol Med ; 29(1): 89, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37403081

RESUMEN

BACKGROUND: Breast cancer is one of the most common malignancies occurred in female around the globe. Recent studies have revealed the crucial characters of miRNA and genes, as well as the essential roles of epigenetic regulation in breast cancer initiation and progression. In our previous study, miR-142-3p was identified as a tumor suppressor and led to G2/M arrest through targeting CDC25C. However, the specific mechanism is still uncertain. METHODS: We identified PAX5 as the upstream regulator of miR-142-5p/3p through ALGGEN website and verified by series of assays in vitro and in vivo. The expression of PAX5 in breast cancer was detected by qRT-PCR and western blot. Besides, bioinformatics analysis and BSP sequencing were performed to analyze the methylation of PAX5 promoter region. Finally, the binding sites of miR-142 on DNMT1 and ZEB1 were predicted by JASPAR, and proved by luciferase reporter assay, ChIP analysis and co-IP. RESULTS: PAX5 functioned as a tumor suppressor by positive regulation of miR-142-5p/3p both in vitro and in vivo. The expression of PAX5 was regulated by the methylation of its promoter region induced by DNMT1 and ZEB1. In addition, miR-142-5p/3p could regulate the expression of DNMT1 and ZEB1 through binding with their 3'UTR region, respectively. CONCLUSION: In summary, PAX5-miR-142-DNMT1/ZEB1 constructed a negative feedback loop to regulate the progression of breast cancer, which provided emerging strategies for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Humanos , Femenino , Línea Celular Tumoral , Retroalimentación , Neoplasias de la Mama/patología , Apoptosis/genética , Epigénesis Genética , Puntos de Control de la Fase G2 del Ciclo Celular , MicroARNs/genética , MicroARNs/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Factor de Transcripción PAX5/genética , Factor de Transcripción PAX5/metabolismo
13.
Plant Cell ; 32(7): 2251-2270, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32358074

RESUMEN

Strigolactones (SLs) and karrikins (KARs) are related butenolide signaling molecules that control plant development. In Arabidopsis (Arabidopsis thaliana), they are recognized separately by two closely related receptors but use the same F-box protein MORE AXILLARY GROWTH2 (MAX2) for signal transduction, targeting different members of the SMAX1-LIKE (SMXL) family of transcriptional repressors for degradation. Both signals inhibit hypocotyl elongation in seedlings, raising the question of whether signaling is convergent or parallel. Here, we show that synthetic SL analog GR244DO enhanced the interaction between the SL receptor DWARF14 (D14) and SMXL2, while the KAR surrogate GR24 ent-5DS induced association of the KAR receptor KARRIKIN INSENSITIVE2 (KAI2) with SMAX1 and SMXL2. Both signals trigger polyubiquitination and degradation of SMXL2, with GR244DO dependent on D14 and GR24 ent-5DS dependent mainly on KAI2. SMXL2 is critical for hypocotyl responses to GR244DO and functions redundantly with SMAX1 in hypocotyl response to GR24 ent-5DS Furthermore, GR244DO induced response of D14-LIKE2 and KAR-UP F-BOX1 through SMXL2, whereas GR24 ent-5DS induced expression of these genes via both SMAX1 and SMXL2. These findings demonstrate that both SLs and KARs could trigger polyubiquitination and degradation of SMXL2, thus uncovering an unexpected but important convergent pathway in SL- and KAR-regulated gene expression and hypocotyl elongation.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiología , Furanos/metabolismo , Compuestos Heterocíclicos con 3 Anillos/metabolismo , Hipocótilo/crecimiento & desarrollo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lactonas/metabolismo , Piranos/metabolismo , Secuencias de Aminoácidos , Arabidopsis/efectos de los fármacos , Proteínas de Arabidopsis/genética , Proteínas Portadoras/metabolismo , Furanos/farmacología , Regulación de la Expresión Génica de las Plantas , Compuestos Heterocíclicos con 3 Anillos/farmacología , Hidrolasas/genética , Hidrolasas/metabolismo , Hipocótilo/efectos de los fármacos , Hipocótilo/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Lactonas/farmacología , Complejos Multiproteicos/metabolismo , Plantas Modificadas Genéticamente , Proteolisis , Piranos/farmacología , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Transducción de Señal , Ubiquitinación
14.
Inorg Chem ; 62(27): 10792-10804, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37377247

RESUMEN

Reactions of achiral di(2-pyridyl)methyl substituted aminophenols L1-6H (2-{N-R3-N-[di(2-pyridyl)methyl]aminomethyl}-4-R1-6-R2-C6H2OH: R1 = R2 = tBu, R3 = nBu (L1H), R3 = nhexyl (L2H), R3 = cyclohexyl (L3H); R1 = R2 = cumyl, R3 = nBu (L4H), R3 = nhexyl (L5H), R3 = cyclohexyl (L6H)) with {Mg[N(SiMe3)2]2}2 ([L1-6H]:[Mg] = 1:1) afforded a series of magnesium silylamido complexes 1-6. In the solid state, the magnesium center of 3, 4, and 6 is penta-coordinated by the tetradentate aminophenloate ligand and one silylamido ligand to form a seriously distorted square-pyramidal geometry as confirmed by X-ray crystallography diffraction analysis. VT 1H NMR and ROESY experiments further indicate that these magnesium complexes are also five-coordinated in solutions where the coordination of either of the two pyridyl pendants to the magnesium center is maintained. Complexes 1-6 are highly active toward the ring-opening polymerization of rac-lactide (rac-LA) at r.t. both in toluene and in tetrahydrofuran, capable of polymerizing 500 equiv of monomer to high conversions just within minutes. Among them, complex 3 exhibited the highest iso-stereoselectivity, affording moderately isotactic polylactide in toluene (Pm = 0.75). It is found that the isoselectivities and activities of these magnesium complexes toward the polymerization of rac-LA are closely associated with the substituents at the ortho-position of the phenoxide unit and on the skeleton nitrogen atom of the ligand. On the basis of NMR spectroscopic studies, the formation of isotactic PLAs with dominant stereoblock sequences was witnessed by using these magnesium complexes as initiators, and the inequivalent coordination of two pyridyl pendant arms in these magnesium complexes might be the source of exerting isoselective control.

15.
Immunol Invest ; 52(6): 735-748, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37409941

RESUMEN

BACKGROUND: CAR-T is emerging as an effective treatment strategy for hematologic malignancies, however its effectiveness for treating solid tumors, such as Hepatocellular Carcinoma (HCC) is limited. Here, we screened a variety of CAR-T cells that target c-Met to investigate their potential to induce HCC cell death in vitro. METHODS: Human T cells were transduced to express CARs by lentiviral vector transfection. c-Met expression in human HCC cell lines and CARs expression were monitored by flow cytometry. Tumor cell killing was evaluated by Luciferase Assay System Kit. The concentrations of cytokine were tested by Enzyme-linked immunosorbent assays. Knock down and overexpression studies targeting c-Met were conducted to assess the targeting specificity of CARs. RESULTS: We found that CAR T cells expressing a minimal amino-terminal polypeptide sequence comprising the first kringle (kringle 1) domain (denoted as NK1 CAR-T cells), efficiently killed HCC cell lines that expressed high levels of the HGF receptor c-Met. Furthermore, we report that while NK1 CAR-T cells were efficient at targeting SMMC7221 cells for destruction, and its potency was significantly attenuated in parallel experiments with cells stably expressing short hairpin RNAs (shRNAs) that suppressed c-Met expression. Correspondingly, overexpression of c-Met in the embryonic kidney cell line HEK293T led to their enhanced killing by NK1 CAR-T cells. CONCLUSION: Our studies demonstrate that a minimal amino-terminal polypeptide sequence comprising the kirngle1 domain of HGF is highly relevant to the design of effective CAR-T cell therapies that kill HCC cells expressing high levels of c-Met.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Células HEK293 , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Línea Celular Tumoral , Inmunoterapia Adoptiva , Citocinas/metabolismo , Linfocitos T/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Factor de Crecimiento de Hepatocito/metabolismo
16.
Epilepsy Behav ; 138: 109035, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535109

RESUMEN

Brain neuron activity is closely related to cerebral blood flow (CBF) changes. Alterations in the regional homogeneity (ReHo) and CBF occur in patients with magnetic resonance imaging negative focal epilepsy (FEP-MRI-). However, the coupling alterations of ReHo and CBF in FEP-MRI- remain unclear. The study aims to explore neurovascular coupling alterations and their clinical implication in FEP-MRI-. We collected resting-state magnetic resonance imaging (MRI) data from 31 healthy controls (HCs) and 48 patients with FEP-MRI-,including three-dimensional (3D) T1-weighted imaging, 3D arterial spin labeling (ASL) imaging,and resting-state functional MRI (rs-fMRI). The CBF and ReHo values were calculated from the ASL and rs-fMRI data, respectively. The CBF/ReHo ratio per voxel and whole-brain CBF-ReHo coupling were compared between the two groups. Correlation analysis involved the CBF/ReHo ratio and clinical indicators in FEP-MRI-. Patients with FEP-MRI- showed significantly increased cross-subject CBF-ReHo and global cross-voxel CBF-ReHo coupling. The CBF/ReHo ratio was higher in the bilateral orbitofrontal gyrus, right parietal lobe, and right middle frontal gyrus of patients with FEP-MRI-. Nevertheless, this ratio was lower in the bilateral supplementary motor areas, the left middle and posterior cingulate gyrus, and the right central sulcus cover. The CBF/ReHo ratio was markedly correlated with cognitive function, memory, intelligence, and epilepsy duration in the above abnormal brain regions. CBF/ReHo ratio may be useful as an indicator of neuropathological mechanisms. These results support the hypothesis that CBF/ReHo ratio relates to the neuropathological mechanisms of FEP-MRI-. Furthermore, it offers new perspectives for studying the mechanisms of MRI-negative epilepsy.


Asunto(s)
Epilepsias Parciales , Acoplamiento Neurovascular , Humanos , Encéfalo , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico/métodos , Marcadores de Spin
17.
Vascular ; : 17085381231194149, 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37616577

RESUMEN

OBJECTIVES: To perform a correlation analysis on the structural and functional changes of the carotid artery in patients with H-type hypertension. METHODS: Outpatients and inpatients with hypertension in our hospital between 2017 and 2018 were selected and divided into the H-type hypertension group (primary hypertension + plasma homocysteine ≥ 10 umol/l) (n = 30) and the simple hypertension group (primary hypertension + plasma Hcy < 10 umol/l) (n = 30) based on the plasma homocysteine (Hcy), and 30 healthy people were included in the control group. Thickness and stiffness parameters of the intima of the carotid artery (compliance coefficient [CC], stiffness index [ß], and pulse wave velocity [PWV]) were measured for all study participants using ultrasound radiofrequency signal-based quality intima-media thickness (QIMT) and quantitative arterial stiffness (QAS) for contrast analysis. RESULTS: Indexes such as QIMT, ß, and PWV of the carotid artery were significantly higher, and the CC was significantly lower in the H-type hypertension group and simple hypertension group than the control group (p < .05), and the difference was statistically significant; these indexes were significantly higher in the H-type hypertension group than in the simple hypertension group, and the CC was significantly lower than in the control group (p < .05), and the difference was statistically significant. CONCLUSIONS: Hypertension can accelerate structural and functional changes of the carotid artery intima, with these changes being more significant in H-type hypertension. The ultrasound radiofrequency technique can be used to quantitatively evaluate the structure and function of the carotid artery in patients with H-type hypertension.

18.
Psychol Health Med ; 27(1): 265-279, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33573426

RESUMEN

The prevalence of and risk factors for uncertainty stress among residents during the COVID-19 pandemic remain unclear. An online cross-sectional survey was conducted to explore and identify the risk factors for high perceived uncertainty stress among the general public in China during the COVID-19 outbreak. Information about the respondents' socioeconomic characteristics, knowledge of and attitudes towards COVID-19, perceived uncertainty stress, social capital, anxiety, and depressive symptoms was collected and analysed. Among the 1205 respondents, 45.3% (546) reported a high level of uncertainty stress. Multiple linear regression analysis indicated that anxiety (ß=3.871,P<0.001) and depression symptoms (ß=2.458, P<0.001), family residence (in towns or rural areas) (ß=0.947, P<0.001), lack of support for local epidemic control strategies (ß=1.253, P<0.001), worry about the pandemic (ß=1.191, P<0.001), and symptoms of weakness among family members (ß=1.525, P=0.002) were positively associated with perceived uncertainty stress. Cognitive social capital (ß=-0.883, P<0.001) and social networks (ß=-0.726, P<0.001) were negatively, but social participation (ß=0.714, P<0.001) was positively associated with perceived uncertainty stress. Our findings identify factors associated with a higher level of uncertainty stress and should be helpful in the consideration of effective policies and interventions for uncertainty stress during the initial phases of public health emergencies.


Asunto(s)
COVID-19 , Pandemias , Ansiedad/epidemiología , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Humanos , SARS-CoV-2 , Encuestas y Cuestionarios , Incertidumbre
19.
J Exp Bot ; 72(2): 510-524, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33005924

RESUMEN

Acyl-CoA:diacylglycerol acyltransferase (DGAT) catalyzes the final committed step in triacylglycerol biosynthesis in eukaryotes. In microalgae, the copy number of DGAT genes is extraordinarily expanded, yet the functions of many DGATs remain largely unknown. This study revealed that microalgal DGAT can function as a lysophosphatidic acyltransferase (LPAAT) both in vitro and in vivo while losing its original function as DGAT. Among the five DGAT-encoding genes identified and cloned from the green microalga Haematococcus pluvialis, four encoded HpDGATs that showed triacylglycerol synthase activities in yeast functional complementation analyses; the exception was one of the type II DGAT encoding genes, HpDGTT2. The hydrophobic recombinant HpDGTT2 protein was purified in soluble form and was found to function as a LPAAT via enzymatic assay. Introducing this gene into the green microalga Chlamydomonas reinhardtii led to retarded cellular growth, enlarged cell size, and enhanced triacylglycerol accumulation, identical to the phenotypes of transgenic strains overexpressing CrLPAAT. This study provides a framework for dissecting uncharacterized DGATs, and could pave the way to decrypting the structure-function relationship of this large group of enzymes that are critical to lipid biosynthesis.


Asunto(s)
Chlamydomonas reinhardtii , Microalgas , Aciltransferasas , Diacilglicerol O-Acetiltransferasa/genética , Diglicéridos , Microalgas/genética , Triglicéridos
20.
Br J Nutr ; 126(5): 652-662, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-33222701

RESUMEN

Nutrition in early life has a long-term influence on later health. In order to the explore effects of in ovo feeding (IOF) of vitamin C on splenic development, splenic metabolism and apoptosis were detected in embryo, adult chickens and in vitro. A total of 360 fertile eggs were selected and randomly assigned to control (CON) and vitamin C (VC) groups which were injected with saline and vitamin C on embryonic day 11, respectively. Functional enrichment of differentially expressed genes by transcriptome on embryonic day 19 suggested that purine nucleotide metabolism might be a potential pathway for the IOF of vitamin C to regulate spleen development. Additionally, the IOF of vitamin C significantly increased splenic vitamin C content on post-hatch day 21. Meanwhile, the splenic expression of adenosine deaminase, serine/threonine kinase 1 and proliferating cell nuclear antigen was down-regulated, whereas the expression of cysteinyl aspartate specific proteinase 9 was up-regulated in the VC group. On post-hatch day 42, the IOF of vitamin C significantly down-regulated the splenic expression of B-cell lymphoma 2 and increased the mRNA level of cysteinyl aspartate specific proteinase 9. The IOF of vitamin C could regulate the expression of genes related to adenylate metabolism and increased the apoptosis rate in vitro, which is consistent with the result in vivo. In conclusion, the IOF of vitamin C regulated splenic development and maturation by affecting purine nucleotide metabolism pathway and promoting apoptosis.


Asunto(s)
Apoptosis , Ácido Ascórbico , Pollos , Nucleótidos de Purina/metabolismo , Bazo/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Ácido Ascórbico/administración & dosificación , Péptido Hidrolasas , Vitaminas/administración & dosificación
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