Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Plant Cell ; 35(6): 2251-2270, 2023 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-36807983

RESUMEN

The plant cuticle, a structure primarily composed of wax and cutin, forms a continuous coating over most aerial plant surfaces. The cuticle plays important roles in plant tolerance to environmental stress, including stress imposed by drought. Some members of the 3-KETOACYL-COA SYNTHASE (KCS) family are known to act as metabolic enzymes involved in cuticular wax production. Here we report that Arabidopsis (Arabidopsis thaliana) KCS3, which was previously shown to lack canonical catalytic activity, instead functions as a negative regulator of wax metabolism by reducing the enzymatic activity of KCS6, a key KCS involved in wax production. We demonstrate that the role of KCS3 in regulating KCS6 activity involves physical interactions between specific subunits of the fatty acid elongation complex and is essential for maintaining wax homeostasis. We also show that the role of the KCS3-KCS6 module in regulating wax synthesis is highly conserved across diverse plant taxa from Arabidopsis to the moss Physcomitrium patens, pointing to a critical ancient and basal function of this module in finely regulating wax synthesis.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Mutación , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
2.
Nucleic Acids Res ; 52(W1): W489-W497, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38752486

RESUMEN

Kinase-targeted inhibitors hold promise for new therapeutic options, with multi-target inhibitors offering the potential for broader efficacy while minimizing polypharmacology risks. However, comprehensive experimental profiling of kinome-wide activity is expensive, and existing computational approaches often lack scalability or accuracy for understudied kinases. We introduce KinomeMETA, an artificial intelligence (AI)-powered web platform that significantly expands the predictive range with scalability for predicting the polypharmacological effects of small molecules across the kinome. By leveraging a novel meta-learning algorithm, KinomeMETA efficiently utilizes sparse activity data, enabling rapid generalization to new kinase tasks even with limited information. This significantly expands the repertoire of accurately predictable kinases to 661 wild-type and clinically-relevant mutant kinases, far exceeding existing methods. Additionally, KinomeMETA empowers users to customize models with their proprietary data for specific research needs. Case studies demonstrate its ability to discover new active compounds by quickly adapting to small dataset. Overall, KinomeMETA offers enhanced kinome virtual profiling capabilities and is positioned as a powerful tool for developing new kinase inhibitors and advancing kinase research. The KinomeMETA server is freely accessible without registration at https://kinomemeta.alphama.com.cn/.


Asunto(s)
Internet , Polifarmacología , Inhibidores de Proteínas Quinasas , Proteínas Quinasas , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Proteínas Quinasas/metabolismo , Proteínas Quinasas/química , Proteínas Quinasas/genética , Humanos , Programas Informáticos , Algoritmos , Inteligencia Artificial , Descubrimiento de Drogas/métodos
3.
Plant Physiol ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630866

RESUMEN

Ginkgo (Ginkgo biloba L.) is one of the earliest extant species in seed plant phylogeny. Embryo development patterns can provide fundamental evidence for the origin, evolution, and adaptation of seeds. However, the architectural and morphological dynamics during embryogenesis in Ginkgo biloba (G. biloba) remain elusive. Herein, we obtained over 2200 visual slices from three stages of embryo development using micro-computed tomography imaging with improved staining methods. Based on 3D spatio-temporal pattern analysis, we found that a shoot apical meristem with seven highly differentiated leaf primordia, including apical and axillary leaf buds, is present in mature Ginkgo embryos. 3D rendering from the front, top, and side views showed two separate transport systems of tracheids located in the hypocotyl and cotyledon, representing a unique pattern of embryogenesis. Furthermore, the morphological dynamic analysis of secretory cavities indicated their strong association with cotyledons during development. In addition, we identified genes GbLBD25a (lateral organ boundaries domain 25a), GbCESA2a (cellulose synthase 2a), GbMYB74c (myeloblastosis 74c), GbPIN2 (PIN-FORMED 2) associated with vascular development regulation, and GbWRKY1 (WRKYGOK 1), GbbHLH12a (basic helix-loop-helix 12a), GbJAZ4 (jasmonate zim-domain 4) potentially involved in the formation of secretory cavities. Moreover, we found that flavonoid accumulation in mature embryos could enhance post-germinative growth and seedling establishment in harsh environments. Our 3D spatial reconstruction technique combined with multi-omics analysis opens avenues for investigating developmental architecture and molecular mechanisms during embryogenesis and lays the foundation for evolutionary studies of embryo development and maturation.

4.
Bioinformatics ; 38(3): 792-798, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34643666

RESUMEN

MOTIVATION: The acid dissociation constant (pKa) is a critical parameter to reflect the ionization ability of chemical compounds and is widely applied in a variety of industries. However, the experimental determination of pKa is intricate and time-consuming, especially for the exact determination of micro-pKa information at the atomic level. Hence, a fast and accurate prediction of pKa values of chemical compounds is of broad interest. RESULTS: Here, we compiled a large-scale pKa dataset containing 16 595 compounds with 17 489 pKa values. Based on this dataset, a novel pKa prediction model, named Graph-pKa, was established using graph neural networks. Graph-pKa performed well on the prediction of macro-pKa values, with a mean absolute error around 0.55 and a coefficient of determination around 0.92 on the test dataset. Furthermore, combining multi-instance learning, Graph-pKa was also able to automatically deconvolute the predicted macro-pKa into discrete micro-pKa values. AVAILABILITY AND IMPLEMENTATION: The Graph-pKa model is now freely accessible via a web-based interface (https://pka.simm.ac.cn/). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Redes Neurales de la Computación , Agua , Agua/química
5.
Nucleic Acids Res ; 49(D1): D1170-D1178, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33104791

RESUMEN

One of the most prominent topics in drug discovery is efficient exploration of the vast drug-like chemical space to find synthesizable and novel chemical structures with desired biological properties. To address this challenge, we created the DrugSpaceX (https://drugspacex.simm.ac.cn/) database based on expert-defined transformations of approved drug molecules. The current version of DrugSpaceX contains >100 million transformed chemical products for virtual screening, with outstanding characteristics in terms of structural novelty, diversity and large three-dimensional chemical space coverage. To illustrate its practical application in drug discovery, we used a case study of discoidin domain receptor 1 (DDR1), a kinase target implicated in fibrosis and other diseases, to show DrugSpaceX performing a quick search of initial hit compounds. Additionally, for ligand identification and optimization purposes, DrugSpaceX also provides several subsets for download, including a 10% diversity subset, an extended drug-like subset, a drug-like subset, a lead-like subset, and a fragment-like subset. In addition to chemical properties and transformation instructions, DrugSpaceX can locate the position of transformation, which will enable medicinal chemists to easily integrate strategy planning and protection design.


Asunto(s)
Bases de Datos de Compuestos Químicos , Bases de Datos Farmacéuticas , Descubrimiento de Drogas/métodos , Drogas en Investigación/farmacología , Medicamentos bajo Prescripción/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Receptor con Dominio Discoidina 1/antagonistas & inhibidores , Receptor con Dominio Discoidina 1/química , Receptor con Dominio Discoidina 1/metabolismo , Diseño de Fármacos , Drogas en Investigación/química , Fibrosis/tratamiento farmacológico , Humanos , Internet , Ligandos , Medicamentos bajo Prescripción/química , Bibliotecas de Moléculas Pequeñas/química , Programas Informáticos
6.
J Orthop Sci ; 28(5): 1105-1112, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35864029

RESUMEN

BACKGROUND: This study aims to compare therapeutic effects of two methods in complicated subtrochanteric femur fractures surgery: intramedullary nail fixation assisted with lateral monocortical locking plate versus intramedullary nail fixation assisted with supplementary cables. METHODS: From June 2015 to June 2020, seventy-seven patients with complex subtrochanteric fractures (i.e., Seinsheimer's classification type IV or V) were included in this study. Thirty-six patients (plate group) were operated using the intramedullary nail fixation assisted by lateral monocortical locking plate, and forty-one patients (cable group) were using the intramedullary nail fixation assisted by cables. The clinical information and demographic results were collected and compared. RESULTS: Operation time of plate group was shorter than cable group and the Incisions length of plate group was longer. The fluoroscopy times were 22.8 ± 8.2 in plate group and 33.0 ± 9.0 in cable group (p < 0.01). Compared with the cable group, patients in plate group used less cerclage cables (p < 0.01). Patients in the plate group has less medial cortex displacement compared with the cable group. (p = 0.038). As for the angular difference of neck shaft angle between operated hip and uninjured hip, plate group has less difference compared with the cable group. Time to union was 14.2 ± 3.1 weeks in plate group which is shorter than the cable group (17.9 ± 4.8 weeks). In terms of follow up period, number of malunion, Harris hip score, walking ability and traumatic hip rating scale, no significant differences were detected. CONCLUSIONS: Our results suggest that using lateral monocortical plate as an auxiliary way may have a longer surgical incision and more intraoperative blood loss, however, the operation time is shorter, the fluoroscopy times is less, and the time to union is shorter. Intramedullary nail fixation assisted by lateral monocortical locking plate may be a new option for patients with complex subtrochanteric femur fractures.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Humanos , Estudios Retrospectivos , Clavos Ortopédicos , Fijación Intramedular de Fracturas/métodos , Resultado del Tratamiento , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/cirugía , Fémur
7.
Chin J Cancer Res ; 34(1): 11-27, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35355934

RESUMEN

Objective: Cleavage and polyadenylation specific factor 6 (CPSF6) has been documented as an oncoprotein in different types of cancer. However, functions of CPSF6 have not been investigated yet in esophageal squamous cell carcinoma (ESCC). Here, we aimed to investigate the potential clinical values and biological functions of CPSF6 in ESCC. Methods: For determining the expression level of CPSF6 in ESCC patients, we analyzed published data, performed quantitative real-time polymerase chain reaction (RT-qPCR) and immunohistochemistry assays. Kaplan-Meier curves and log-rank tests were used for survival analyses. GO and KEGG analyses were done for CPSF6-related genes. Cell proliferation, colony formation and xenograft assays were conducted to verify the effects of CPSF6 on ESCC. In addition, cell cycle and apoptosis assays were also performed to manifest the functions of CPSF6 and circCPSF6. RNA pulldown and radioimmunoprecipitation (RIP) assays were used for confirming the interaction between circCPSF6 (hsa_circ_0000417) and CPSF6 protein. The regulatory relationship between CPSF6 protein and circCPSF6 was determined by RT-qPCR. Results: We found that CPSF6 was upregulated in ESCC tissues and overexpression of cytoplasmic CPSF6 was associated with poor prognosis. GO and KEGG analyses suggested that CPSF6 could mainly affect cell division in ESCC. Further experiments manifested that CPSF6 promoted cell proliferation and colony formationin vitro. Xenograft assay showed that knockdown of CPSF6 significantly decreased tumor growth rate in vivo. Subsequently, we verified that depletion of CPSF6 led to cell cycle arrest and apoptosis. Finally, we validated that CPSF6, as a circRNA-binding protein, interacted with and regulated its circular isoform circCPSF6 (hsa_circ_0000417), of which depletion also resulted in cell cycle arrest and cell apoptosis in ESCC. Conclusions: These findings gave us insight that overexpression of cytoplasmic CPSF6 protein is associated with poor prognosis in ESCC and CPSF6 may function as an oncoprotein, at least in part, through regulating circCPSF6 expression.

8.
Chin J Cancer Res ; 33(6): 637-648, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35125808

RESUMEN

OBJECTIVE: Increasing evidence has demonstrated that ZNF292 plays a suppressive role in cancer, however, little is known about its function and exact mechanism in esophageal squamous cell carcinoma (ESCC). METHODS: Bioinformatic analysis and immunohistochemistry (IHC) were performed to analyze the role of ZNF292 in affecting the prognosis of ESCC. Cell proliferation and colony formation ability assays were performed to analyze cell growth after inferring the expression of ZNF292. Flow cytometry was used to analyze changes in the cell cycle upon the depletion of ZNF292. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were used to determine the alteration of cell cycle related RNAs and proteins after knocking down ZNF292. MG-132, cycloheximide (CHX) treatment experiments were performed to analyze the change and half-life time of P27 after knockdown of ZNF292. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were used to analyze the transcriptional regulation of SKP2 by ZNF292. RESULTS: We report that low expression of ZNF292 is associated with poor prognosis, and ZNF292 emerges to be highly expressed in adjacent and normal tissues rather than tumor tissues in ESCC. Knockdown of ZNF292 significantly boosts cell growth and S phase entry in ESCC cells. ZNF292 depletion will decrease the expression and half-life time of P27, while knockdown of SKP2 will result in elevated expression of P27. ZNF292 can bind to the promoter region of SKP2, and knockdown of ZNF292 will boost the expression of SKP2. CONCLUSIONS: Knockdown of ZNF292 mediates G1/S cell cycle procession by activating SKP2/P27 signaling in ESCC cells. ZNF292 knockdown promotes SKP2 expression at the transcriptional level, thereby boosting P27 ubiquitin-degradation, and eventually facilitating the S phase entrance.

9.
Chin J Cancer Res ; 31(4): 609-619, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31564804

RESUMEN

OBJECTIVE: Growing evidence indicates that FAT atypical cadherin 1 (FAT1) has aberrant genetic alterations and exhibits potential tumor suppressive function in esophageal squamous cell carcinoma (ESCC). However, the role of FAT1 in ESCC tumorigenesis remains not well elucidated. The aim of this study was to further investigate genetic alterations and biological functions of FAT1, as well as to explore its transcriptional regulation and downstream targets in ESCC. METHODS: The mutations of FAT1 in ESCC were achieved by analyzing a combined study from seven published genomic data, while the copy number variants of FAT1 were obtained from an analysis of our previous data as well as of The Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE) databases using the cBioPortal. The transcriptional regulation of FAT1 expression was investigated by chromatin immunoprecipitation (ChIP) and the luciferase reporter assays. In-cell western, Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to assess the indicated gene expression. In addition, colony formation and Transwell migration/invasion assays were employed to test cell proliferation, migration and invasion. Finally, RNA sequencing was used to study the transcriptomes. RESULTS: FAT1 was frequently mutated in ESCC and was deleted in multiple cancers. Furthermore, the transcription factor E2F1 occupied the promoter region of FAT1, and depletion of E2F1 led to a decrease in transcription activity and mRNA levels of FAT1. Moreover, we found that knockdown of FAT1 promoted KYSE30 and KYSE150 cell proliferation, migration and invasion; while overexpression of FAT1 inhibited KYSE30 and KYSE410 cell proliferation, migration and invasion. In addition, knockdown of FAT1 led to enrichment of the mitogen-activated protein kinase (MAPK) signaling pathway and cell adhesion process. CONCLUSIONS: Our data provided evidence for the tumor suppressive function of FAT1 in ESCC cells and elucidated the transcriptional regulation of FAT1 by E2F1, which may facilitate the understanding of molecular mechanisms of the progression of ESCC.

10.
BMC Cell Biol ; 19(1): 16, 2018 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-30126368

RESUMEN

BACKGROUND: TP53 gene mutations occur in more than 50% of human cancers and the vast majority of these mutations in human cancers are missense mutations, which broadly occur in DNA binding domain (DBD) (Amino acids 102-292) and mainly reside in six "hotspot" residues. TP53 G245C and R273H point mutations are two of the most frequent mutations in tumors and have been verified in several different cancers. In the previous study of the whole genome sequencing (WGS), we found some mutations of TP53 DBD in esophageal squamous cell carcinoma (ESCC) clinical samples. We focused on two high-frequent mutations TP53 p.G245C and TP53 p.R273H and investigated their oncogenic roles in ESCC cell lines, p53-defective cell lines H1299 and HCT116 p53-/-. RESULTS: MTS and colony formation assays showed that mutant TP53 G245C and R273H increased cell vitality and proliferation. Flow cytometry results revealed inhibition of ultraviolet radiation (UV)- and ionizing radiation (IR)- induced apoptosis and disruption of TP53-mediated cell cycle arrest after UV, IR and Nocodazole treatment. Transwell assays indicated that mutant TP53 G245C and R273H enhanced cell migration and invasion abilities. Moreover, western blot revealed that they were able to suppress the expression of TP53 downstream genes in the process of apoptosis and cell cycle arrest induced by UV, which suggests that these two mutations can influence apoptosis and growth arrest might be due, at least in part, to down-regulate the expression of P21, GADD45α and PARP. CONCLUSIONS: These results indicate that mutant TP53 G245C and R273H can lead to more aggressive phenotypes and enhance cancer cell malignancy, which further uncover TP53 function in carcinogenesis and might be useful in clinical diagnosis and therapy of TP53 mutant cancers.


Asunto(s)
Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/patología , Mutación/genética , Proteína p53 Supresora de Tumor/genética , Apoptosis/genética , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Análisis Mutacional de ADN , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Invasividad Neoplásica , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteinas GADD45
11.
BMC Cancer ; 18(1): 17, 2018 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-29298684

RESUMEN

BACKGROUND: The key-stone-pathogen, Porphyromonas gingivalis associates not only with periodontal diseases but with a variety of other chronic diseases such as cancer. We previously reported an association between the presence of Porphyromonas gingivalis in esophageal squamous cell carcinoma (ESCC) and its progression. We now report the diagnostic and prognostic potential of serum immunoglobulin G and A antibodies (IgG/A) against Porphyromonas gingivalis for ESCC. METHODS: An enzyme-linked immunosorbent assay (ELISA) was used to determine the serum levels of Porphyromonas gingivalis IgG and IgA in 96 cases with ESCC, 50 cases with esophagitis and 80 healthy controls. RESULTS: The median serum levels of IgG and IgA for P. gingivalis were significantly higher in ESCC patients than non-ESCC controls. P. gingivalis IgG and IgA in serum demonstrated sensitivities/specificities of 29.17%/96.90% and 52.10%/70.81%, respectively, and combination of IgG and IgA produced a sensitivity/specificity of 68.75%/68.46%. The diagnostic performance of serum P. gingivalis IgA for early ESCC was superior to that of IgG (54.54% vs. 20.45%). Furthermore, high serum levels of P. gingivalis IgG or IgA were associated with worse prognosis of ESCC patients, in particular for patients with stage 0-IIor negative lymphnode metastasis, and ESCC patients with high levels of both IgG and IgA had the worst prognosis. Multivariate analysis revealed that lymph node status, IgG and IgA were independent prognostic factors. CONCLUSIONS: The IgG and IgA for P. gingivalis are potential serum biomarkers for ESCC and combination of IgG and IgA improves the diagnostic and prognostic performance. Furthermore, serum P. gingivalis IgG and IgA can detect early stage ESCC.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Esofágicas/diagnóstico , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Porphyromonas gingivalis/inmunología , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Infecciones por Bacteroidaceae/complicaciones , Infecciones por Bacteroidaceae/inmunología , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/microbiología , Ensayo de Inmunoadsorción Enzimática , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/microbiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Pronóstico , Tasa de Supervivencia
12.
Plant Physiol ; 165(3): 1255-1268, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24812105

RESUMEN

The ECERIFERUM9 (CER9) gene encodes a putative E3 ubiquitin ligase that functions in cuticle biosynthesis and the maintenance of plant water status. Here, we found that CER9 is also involved in abscisic acid (ABA) signaling in seeds and young seedlings of Arabidopsis (Arabidopsis thaliana). The germinated embryos of the mutants exhibited enhanced sensitivity to ABA during the transition from reversible dormancy to determinate seedling growth. Expression of the CER9 gene is closely related to ABA levels and displays a similar pattern to that of ABSCISIC ACID-INSENSITIVE5 (ABI5), which encodes a positive regulator of ABA responses in seeds. cer9 mutant seeds exhibited delayed germination that is independent of seed coat permeability. Quantitative proteomic analyses showed that cer9 seeds had a protein profile similar to that of the wild type treated with ABA. Transcriptomics analyses revealed that genes involved in ABA biosynthesis or signaling pathways were differentially regulated in cer9 seeds. Consistent with this, high levels of ABA were detected in dry seeds of cer9. Blocking ABA biosynthesis by fluridone treatment or by combining an ABA-deficient mutation with cer9 attenuated the phenotypes of cer9. Whereas introduction of the abi1-1, abi3-1, or abi4-103 mutation could completely eliminate the ABA hypersensitivity of cer9, introduction of abi5 resulted only in partial suppression. These results indicate that CER9 is a novel negative regulator of ABA biosynthesis and the ABA signaling pathway during seed germination.

13.
J Exp Bot ; 66(21): 6863-75, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26272902

RESUMEN

The circularly permuted GTPase large subunit GTPase 1 (LSG1) is involved in the maturation step of the 60S ribosome and is essential for cell viability in yeast. Here, an Arabidopsis mutant dig6 (drought inhibited growth of lateral roots) was isolated. The mutant exhibited multiple auxin-related phenotypes, which included reduced lateral root number, altered leaf veins, and shorter roots. Genetic mapping combined with next-generation DNA sequencing identified that the mutation occurred in AtLSG1-2. This gene was highly expressed in regions of auxin accumulation. Ribosome profiling revealed that a loss of function of AtLSG1-2 led to decreased levels of monosomes, further demonstrating its role in ribosome biogenesis. Quantitative proteomics showed that the expression of certain proteins involved in ribosome biogenesis was differentially regulated, indicating that ribosome biogenesis processes were impaired in the mutant. Further investigations showed that an AtLSG1-2 deficiency caused the alteration of auxin distribution, response, and transport in plants. It is concluded that AtLSG1-2 is integral to ribosome biogenesis, consequently affecting auxin homeostasis and plant development.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Ribosómicas/genética , Ribosomas/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Mutación , Proteínas Ribosómicas/metabolismo
14.
J Theor Biol ; 368: 1-12, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25542641

RESUMEN

How do people actually play the iterated snowdrift games, particularly under random rematching protocol is far from well explored. Two sets of laboratory experiments on snowdrift game were conducted to investigate human strategy updating rules. Four groups of subjects were modeled by experience-weighted attraction learning theory at individual-level. Three out of the four groups (75%) passed model validation. Substantial heterogeneity is observed among the players who update their strategies in four typical types, whereas rare people behave like belief-based learners even under fixed pairing. Most subjects (63.9%) adopt the reinforcement learning (or alike) rules; but, interestingly, the performance of averaged reinforcement learners suffered. It is observed that two factors seem to benefit players in competition, i.e., the sensitivity to their recent experiences and the overall consideration of forgone payoffs. Moreover, subjects with changing opponents tend to learn faster based on their own recent experience, and display more diverse strategy updating rules than they do with fixed opponent. These findings suggest that most of subjects do apply reinforcement learning alike updating rules even under random rematching, although these rules may not improve their performance. The findings help evolutionary biology researchers to understand sophisticated human behavioral strategies in social dilemmas.


Asunto(s)
Conducta Cooperativa , Teoría del Juego , Modelos Biológicos , Algoritmos , Evolución Biológica , Análisis por Conglomerados , Humanos , Aprendizaje
15.
J Colloid Interface Sci ; 672: 724-735, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38870763

RESUMEN

The integration of functional nanomaterials with tissue engineering scaffolds has emerged as a promising solution for simultaneously treating malignant bone tumors and repairing resected bone defects. However, achieving a uniform bioactive interface on 3D-printing polymer scaffolds with minimized microstructural heterogeneity remains a challenge. In this study, we report a facile metal-coordination self-assembly strategy for the surface engineering of 3D-printed polycaprolactone (PCL) scaffolds with nanostructured two-dimensional conjugated metal-organic frameworks (cMOFs) consisting of Cu ions and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP). A tunable thickness of Cu-HHTP cMOF on PCL scaffolds was achieved via the alternative deposition of metal ions and HHTP. The resulting composite PCL@Cu-HHTP scaffolds not only demonstrated potent photothermal conversion capability for efficient OS ablation but also promoted the bone repair process by virtue of their cell-friendly hydrophilic interfaces. Therefore, the cMOF-engineered dual-functional 3D-printing scaffolds show promising potential for treating bone tumors by offering sequential anti-tumor effects and bone regeneration capabilities. This work also presents a new avenue for the interface engineering of bioactive scaffolds to meet multifaceted demands in osteosarcoma-related bone defects.

16.
Bioact Mater ; 35: 429-444, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38390528

RESUMEN

Osteoarthritis (OA), a common degenerative disease, is characterized by high disability and imposes substantial economic impacts on individuals and society. Current clinical treatments remain inadequate for effectively managing OA. Organoids, miniature 3D tissue structures from directed differentiation of stem or progenitor cells, mimic native organ structures and functions. They are useful for drug testing and serve as active grafts for organ repair. However, organoid construction requires extracellular matrix-like 3D scaffolds for cellular growth. Hydrogel microspheres, with tunable physical and chemical properties, show promise in cartilage tissue engineering by replicating the natural microenvironment. Building on prior work on SF-DNA dual-network hydrogels for cartilage regeneration, we developed a novel RGD-SF-DNA hydrogel microsphere (RSD-MS) via a microfluidic system by integrating photopolymerization with self-assembly techniques and then modified with Pep-RGDfKA. The RSD-MSs exhibited uniform size, porous surface, and optimal swelling and degradation properties. In vitro studies demonstrated that RSD-MSs enhanced bone marrow mesenchymal stem cells (BMSCs) proliferation, adhesion, and chondrogenic differentiation. Transcriptomic analysis showed RSD-MSs induced chondrogenesis mainly through integrin-mediated adhesion pathways and glycosaminoglycan biosynthesis. Moreover, in vivo studies showed that seeding BMSCs onto RSD-MSs to create cartilage organoid precursors (COPs) significantly enhanced cartilage regeneration. In conclusion, RSD-MS was an ideal candidate for the construction and long-term cultivation of cartilage organoids, offering an innovative strategy and material choice for cartilage regeneration and tissue engineering.

17.
Int J Biol Macromol ; 268(Pt 1): 131619, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692998

RESUMEN

The plant cell wall is a complex, heterogeneous structure primarily composed of cellulose, hemicelluloses, and lignin. Exploring the variations in these three macromolecules over time is crucial for understanding wood formation to enhance chemical processing and utilization. Here, we comprehensively analyzed the chemical composition of cell walls in the trunks of Pinus tabulaeformis using multiple techniques. In situ analysis showed that macromolecules accumulated gradually in the cell wall as the plant aged, and the distribution pattern of lignin was opposite that of polysaccharides, and both showed heterogenous distribution patterns. In addition, gel permeation chromatography (GPC) results revealed that the molecular weights of hemicelluloses decreased while that of lignin increased with age. Two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (2D-HSQC NMR) analysis indicated that hemicelluloses mainly comprised galactoglucomannan and arabinoglucuronoxylan, and the lignin types were mainly comprised guaiacyl (G) and p-hydroxyphenyl (H) units with three main linkage types: ß-O-4, ß-ß, and ß-5. Furthermore, the C-O bond (ß-O-4) signals of lignin decreased while the C-C bonds (ß-ß and ß-5) signals increased over time. Taken together, these findings shed light on wood formation in P. tabulaeformis and lay the foundation for enhancing the processing and use of wood and timber products.


Asunto(s)
Pared Celular , Celulosa , Lignina , Pinus , Polisacáridos , Lignina/química , Pinus/química , Pared Celular/química , Polisacáridos/química , Celulosa/química , Peso Molecular , Árboles/química , Espectroscopía de Resonancia Magnética/métodos , Madera/química
18.
Plant Physiol ; 159(3): 930-44, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22635115

RESUMEN

Mutation of the ECERIFERUM9 (CER9) gene in Arabidopsis (Arabidopsis thaliana) causes elevated amounts of 18-carbon-length cutin monomers and a dramatic shift in the cuticular wax profile (especially on leaves) toward the very-long-chain free fatty acids tetracosanoic acid (C24) and hexacosanoic acid (C26). Relative to the wild type, cer9 mutants exhibit elevated cuticle membrane thickness over epidermal cells and cuticular ledges with increased occlusion of the stomatal pore. The cuticular phenotypes of cer9 are associated with delayed onset of wilting in plants experiencing water deficit, lower transpiration rates, and improved water use efficiency measured as carbon isotope discrimination. The CER9 protein thus encodes a novel determinant of plant drought tolerance-associated traits, one whose deficiency elevates cutin synthesis, redistributes wax composition, and suppresses transpiration. Map-based cloning identified CER9, and sequence analysis predicted that it encodes an E3 ubiquitin ligase homologous to yeast Doa10 (previously shown to target endoplasmic reticulum proteins for proteasomal degradation). To further elucidate CER9 function, the impact of CER9 deficiency on interactions with other genes was examined using double mutant and transcriptome analyses. For both wax and cutin, cer9 showed mostly additive effects with cer6, long-chain acyl-CoA synthetase1 (lacs1), and lacs2 and revealed its role in early steps of both wax and cutin synthetic pathways. Transcriptome analysis revealed that the cer9 mutation affected diverse cellular processes, with primary impact on genes associated with diverse stress responses. The discovery of CER9 lays new groundwork for developing novel cuticle-based strategies for improving the drought tolerance and water use efficiency of crop plants.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Epidermis de la Planta/crecimiento & desarrollo , Ubiquitina-Proteína Ligasas/metabolismo , Agua/fisiología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Clonación Molecular , Sequías , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Metabolismo de los Lípidos , Lípidos , Mutación/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Especificidad de Órganos/genética , Epidermis de la Planta/citología , Epidermis de la Planta/ultraestructura , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tallos de la Planta/metabolismo , Transpiración de Plantas , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Estrés Fisiológico/genética , Transcriptoma/genética , Ubiquitina-Proteína Ligasas/genética , Ceras/metabolismo
19.
Front Bioeng Biotechnol ; 11: 1103611, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36733970

RESUMEN

Stem cell-based therapy has drawn attention as an alternative option for promoting prosthetic osteointegration in osteoporosis by virtue of its unique characteristics. However, estrogen deficiency is the main mechanism of postmenopausal osteoporosis. Estrogen, as an effective antioxidant, deficienncy also results in the accumulation of reactive oxygen species (ROS) in the body, affecting the osteogenic differentiation of stem cells and the bone formation i osteoporosis. In this study, we prepared a ROS-scavenging hydrogel by crosslinking of epigallocatechin-3-gallate (EGCG), 3-acrylamido phenylboronic acid (APBA) and acrylamide. The engineered hydrogel can scavenge ROS efficiently, enabling it to be a cell carrier of bone marrow-derived mesenchymal stem cells (BMSCs) to protect delivered cells from ROS-mediated death and osteogenesis inhibition, favorably enhancing the tissue repair potential of stem cells. Further in vivo investigations seriously demonstrated that this ROS-scavenging hydrogel encapsulated with BMSCs can prominently promote osteointegration of 3D printed microporous titanium alloy prosthesis in osteoporosis, including scavenging accumulated ROS, inducing macrophages to polarize toward M2 phenotype, suppressing inflammatory cytokines expression, and improving osteogenesis related markers (e.g., ALP, Runx-2, COL-1, BSP, OCN, and OPN). This work provides a novel strategy for conquering the challenge of transplanted stem cells cannot fully function in the impaired microenvironment, and enhancing prosthetic osteointegration in osteoporosis.

20.
Plant Physiol ; 157(3): 1079-92, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21949210

RESUMEN

A novel mutant of Arabidopsis (Arabidopsis thaliana), having highly glossy inflorescence stems, postgenital fusion in floral organs, and reduced fertility, was isolated from an ethyl methanesulfonate-mutagenized population and designated glossyhead1 (gsd1). The gsd1 locus was mapped to chromosome 1, and the causal gene was identified as a new allele of Acetyl-Coenzyme A Carboxylase1 (ACC1), a gene encoding the main enzyme in cytosolic malonyl-coenzyme A synthesis. This, to our knowledge, is the first mutant allele of ACC1 that does not cause lethality at the seed or early germination stage, allowing for the first time a detailed analysis of ACC1 function in mature tissues. Broad lipid profiling of mature gsd1 organs revealed a primary role for ACC1 in the biosynthesis of the very-long-chain fatty acids (C(20:0) or longer) associated with cuticular waxes and triacylglycerols. Unexpectedly, transcriptome analysis revealed that gsd1 has limited impact on any lipid metabolic networks but instead has a large effect on environmental stress-responsive pathways, especially senescence and ethylene synthesis determinants, indicating a possible role for the cytosolic malonyl-coenzyme A-derived lipids in stress response signaling.


Asunto(s)
Acetil-CoA Carboxilasa/química , Acetil-CoA Carboxilasa/metabolismo , Alelos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Epidermis de la Planta/enzimología , Ceras/metabolismo , Acetil-CoA Carboxilasa/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , ADN de Plantas/genética , Ácidos Grasos/metabolismo , Regulación de la Expresión Génica de las Plantas , Prueba de Complementación Genética , Lípidos , Modelos Biológicos , Datos de Secuencia Molecular , Mutación/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Especificidad de Órganos/genética , Permeabilidad , Epidermis de la Planta/metabolismo , Epidermis de la Planta/ultraestructura , Raíces de Plantas/metabolismo , Polimorfismo Genético , Estructura Terciaria de Proteína , Semillas/metabolismo , Transcriptoma/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA