Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
J Biomed Mater Res A ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39228141

RESUMEN

Early healing of bone defects is still a clinical challenge. Many bone-filling materials have been studied, among which photocrosslinked alginate has received significant attention due to its good biocompatibility and morphological plasticity. Although it has been confirmed that photocrosslinked alginate can be used as an extracellular matrix for 3D cell culture, it lacks osteogenesis-related biological functions. This study constructed a copper ions-photo dual-crosslinked alginate hydrogel scaffold by controlling the copper ion concentration. The scaffolds were shaped by photocrosslinking and then endowed with biological functions by copper ions crosslinking. According to in vitro research, the dual-crosslinked hydrogel increased the compressive strength and favored copper dose-dependent osteoblast differentiation and cell surface adherence of rat bone marrow mesenchymal stem cells and the expression of type I collagen (Col1), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), vascular endothelial growth factor (VEGF). In addition, hydrogel scaffolds were implanted into rat skull defects, and more angiogenesis and osteogenesis could be observed in in vivo studies. The above results show that the copper-photo-crosslinked hydrogel scaffold has excellent osseointegration properties and can potentially promote angiogenesis and early healing of bone defects, providing a reference solution for bone tissue engineering materials.

2.
Org Biomol Chem ; 22(38): 7767-7785, 2024 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-39246045

RESUMEN

Glycan is an essential cell component that usually exists in either a free form or a glycoconjugated form. Glycosylation affects the regulatory function of glycoconjugates in health and disease development, indicating the key role of glycan in organisms. Because of the complexity and diversity of glycan structures, it is challenging to prepare structurally well-defined glycans, which hinders the investigation of biological functions at the molecular level. Chemoenzymatic synthesis is an attractive approach for preparing complex glycans, because it avoids tedious protecting group manipulations in chemical synthesis and ensures high regio- and stereo-selectivity of glucosides during glycan assembly. Herein, enzymes, such as glycosyltransferases (GTs) and glycosidases (GHs), and sugar donors involved in the chemoenzymatic synthesis of human glycans are initially discussed. Many state-of-the-art chemoenzymatic methodologies are subsequently displayed and summarized to illustrate the development of synthetic human glycans, for example, N- and O-linked glycans, human milk oligosaccharides, and glycosaminoglycans. Thus, we provide an overview of recent chemoenzymatic synthetic designs and applications for synthesizing complex human glycans, along with insights into the limitations and perspectives of the current methods.


Asunto(s)
Polisacáridos , Humanos , Polisacáridos/química , Polisacáridos/biosíntesis , Polisacáridos/síntesis química , Polisacáridos/metabolismo , Glicosiltransferasas/metabolismo , Glicosiltransferasas/química , Glicósido Hidrolasas/metabolismo , Glicosilación , Técnicas de Química Sintética
3.
Nat Commun ; 15(1): 5163, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886381

RESUMEN

As the most abundant organic substances in nature, carbohydrates are essential for life. Understanding how carbohydrates regulate proteins in the physiological and pathological processes presents opportunities to address crucial biological problems and develop new therapeutics. However, the diversity and complexity of carbohydrates pose a challenge in experimentally identifying the sites where carbohydrates bind to and act on proteins. Here, we introduce a deep learning model, DeepGlycanSite, capable of accurately predicting carbohydrate-binding sites on a given protein structure. Incorporating geometric and evolutionary features of proteins into a deep equivariant graph neural network with the transformer architecture, DeepGlycanSite remarkably outperforms previous state-of-the-art methods and effectively predicts binding sites for diverse carbohydrates. Integrating with a mutagenesis study, DeepGlycanSite reveals the guanosine-5'-diphosphate-sugar-recognition site of an important G-protein coupled receptor. These findings demonstrate DeepGlycanSite is invaluable for carbohydrate-binding site prediction and could provide insights into molecular mechanisms underlying carbohydrate-regulation of therapeutically important proteins.


Asunto(s)
Aprendizaje Profundo , Sitios de Unión , Carbohidratos/química , Unión Proteica , Redes Neurales de la Computación , Humanos , Proteínas/metabolismo , Proteínas/química , Modelos Moleculares
4.
JACS Au ; 4(5): 2005-2018, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38818065

RESUMEN

Core fucosylation, a special type of N-linked glycosylation, is important in tumor proliferation, invasion, metastatic potential, and therapy resistance. However, the core-fucosylated glycoproteome has not been extensively profiled due to the low abundance and poor ionization efficiency of glycosylated peptides. Here, a "one-step" strategy has been described for protein core-fucosylation characterization in biological samples. Core-fucosylated peptides can be selectively labeled with a glycosylated probe, which is linked with a temperature-sensitive poly(N-isopropylacrylamide) (PNIPAM) polymer, by mutant endoglycosidase (EndoF3-D165A). The labeled probe can be further removed by wild-type endoglycosidase (EndoF3) in a traceless manner for mass spectrometry (MS) analysis. The feasibility and effectiveness of the "one-step" strategy are evaluated in bovine serum albumin (BSA) spiked with standard core-fucosylated peptides, H1299, and Jurkat cell lines. The "one-step" strategy is then employed to characterize core-fucosylated sites in human lung adenocarcinoma, resulting in the identification of 2494 core-fucosylated sites distributed on 1176 glycoproteins. Further data analysis reveals that 196 core-fucosylated sites are significantly upregulated in tumors, which may serve as potential drug development targets or diagnostic biomarkers. Together, this "one-step" strategy has great potential for use in global and in-depth analysis of the core-fucosylated glycoproteome to promote its mechanism research.

5.
J Am Chem Soc ; 146(19): 13356-13366, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38602480

RESUMEN

The crucial roles that glycans play in biological systems are determined by their structures. However, the analysis of glycan structures still has numerous bottlenecks due to their inherent complexities. The nanopore technology has emerged as a powerful sensor for DNA sequencing and peptide detection. This has a significant impact on the development of a related research area. Currently, nanopores are beginning to be applied for the detection of simple glycans, but the analysis of complex glycans by this technology is still challenging. Here, we designed an engineered α-hemolysin nanopore M113R/T115A to achieve the sensing of complex glycans at micromolar concentrations and under label-free conditions. By extracting characteristic features to depict a three-dimensional (3D) scatter plot, glycans with different numbers of functional groups, various chain lengths ranging from disaccharide to decasaccharide, and distinct glycosidic linkages could be distinguished. Molecular dynamics (MD) simulations show different behaviors of glycans with ß1,3- or ß1,4-glycosidic bonds in nanopores. More importantly, the designed nanopore system permitted the discrimination of each glycan isomer with different lengths in a mixture with a separation ratio of over 0.9. This work represents a proof-of-concept demonstration that complex glycans can be analyzed using nanopore sequencing technology.


Asunto(s)
Simulación de Dinámica Molecular , Nanoporos , Polisacáridos , Polisacáridos/química , Proteínas Hemolisinas/química , Ingeniería de Proteínas
6.
Curr Opin Chem Biol ; 80: 102460, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678979

RESUMEN

Protein glycosylation is one of the most common and important post-translational modifications of proteins involved in regulating glycoprotein functions. The chemoenzymatic glycan labeling strategy allows rapid, efficient, and selective interrogation of glycoproteins. Glycoproteomics identifies protein glycosylation events at a large scale, providing information such as peptide sequences, glycan structures, and glycosylated sites. This review discusses the recent development of chemoenzymatic labeling strategies for glycoprotein analysis, mainly including glycoprotein and glycosite profiling. Furthermore, we highlight the chemoenzymatic enrichment approaches in mass spectrometry analysis for three classes of glycan modifications, including N-glycosylation, O-GlcNAcylation, and mucin-type O-glycosylation. Finally, we highlight the emerging trends in new tools and cutting-edge technologies available for glycoproteomic research.


Asunto(s)
Glicoproteínas , Proteómica , Glicosilación , Glicoproteínas/metabolismo , Glicoproteínas/química , Humanos , Proteómica/métodos , Polisacáridos/metabolismo , Polisacáridos/química , Procesamiento Proteico-Postraduccional , Animales , Espectrometría de Masas/métodos , Coloración y Etiquetado/métodos
7.
Adv Sci (Weinh) ; 11(24): e2308522, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582526

RESUMEN

Glycans are complex biomolecules that encode rich information and regulate various biological processes, such as fertilization, host-pathogen binding, and immune recognition, through interactions with glycan-binding proteins. A key driving force for glycan-protein recognition is the interaction between the π electron density of aromatic amino acid side chains and polarized C─H groups of the pyranose (termed the CH-π interaction). However, the relatively weak binding affinity between glycans and proteins has hindered the application of glycan detection and imaging. Here, computational modeling and molecular dynamics simulations are employed to design a chemical strategy that enhances the CH-π interaction between glycans and proteins by genetically incorporating electron-rich tryptophan derivatives into a lectin PhoSL, which specifically recognizes core fucosylated N-linked glycans. This significantly enhances the binding affinity of PhoSL with the core fucose ligand and enables sensitive detection and imaging of core fucosylated glycans in vitro and in xenograft tumors in mice. Further, the study showed that this strategy is applicable to improve the binding affinity of GafD lectin for N-acetylglucosamine-containing glycans. The approach thus provides a general and effective way to manipulate glycan-protein recognition for glycoscience applications.


Asunto(s)
Polisacáridos , Polisacáridos/metabolismo , Polisacáridos/química , Animales , Ratones , Simulación de Dinámica Molecular , Lectinas/metabolismo , Lectinas/química , Unión Proteica , Humanos , Modelos Animales de Enfermedad
8.
Biochem Biophys Rep ; 36: 101559, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37881410

RESUMEN

Background: Recently, the antioxidant properties of the natural compound, selenomethionine (Se-Met), have been recognized. However, its effect on the osteogenic mineralization of the Wnt/ß-Catenin pathway under conditions of oxidative stress and inflammation remain unclear. Methods: This study utilized tert-butyl hydroperoxide (TBHP) to simulate oxidative stress and inflammation. Se-Met was then subsequently used to inhibit these effects in vitro. Results: TBHP induces oxidative stress and inflammatory responses by increasing the expression of reactive oxygen species and NLRP3, whereas decreasing the expression of GPX4, thereby inhibiting the viability of MC3T3-E1 cells. TBHP further promotes lipid peroxidation and damages the ultrastructure of mitochondria. Furthermore, TBHP inhibits the expression levels of ß-Catenin, thereby reducing the activity of the Wnt pathway, which in turn suppresses the osteogenic differentiation and mineralization capacity. Importantly, Se-Met significantly alters the aforementioned responses to enhance expression levels of Wnt pathway-related proteins and improving the osteogenic differentiation and mineralization capacity of the cells. Conclusion: Se-Met enhances antioxidant and anti-inflammatory responses in MC3T3-E1 cells via the Wnt/ß-Catenin signaling pathway to promote osteogenesis. Thus, Se-Met plays a crucial role in the field of bone homeostasis, and presents an opportunity for the future development of novel drugs for treating osteoporosis and maintaining bone stability. However, further detailed preclinical animal studies are required to generate solid and reliable data to aid this development.

9.
J Am Chem Soc ; 145(29): 15879-15887, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-37340703

RESUMEN

Core fucosylation and O-GlcNAcylation are the two most famous protein glycosylation modifications that regulate diverse physiological and pathological processes in living organisms. Here, a "two birds one stone" strategy has been described for the site-specific analysis of core fucosylation and O-GlcNAcylation. Taking advantage of two mutant endoglycosidases (EndoF3-D165A and EndoCC-N180H), which efficiently and specifically recognize core fucose and O-GlcNAc, glycopeptides can be labeled using a biantennary N-glycan probe bearing azido and oxazoline groups. Then, a temperature-sensitive poly(N-isopropylacrylamide) polymer functionalized with dibenzocyclooctyne was introduced to facilitate the enrichment of the labeled glycopeptides from the complex mixture. The captured glycopeptides can be further released enzymatically by wild-type endoglycosidases (EndoF3 and EndoCC) in a traceless manner for mass spectrometry (MS) analysis. The described strategy allows simultaneous profiling of core-fucosylated glycoproteome and O-GlcNAcylated glycoproteome from one complex sample by MS technology and searching the database using different variable modifications.


Asunto(s)
Glicopéptidos , Glicósido Hidrolasas , Glicosilación , Espectrometría de Masas/métodos , Glicopéptidos/química , Glicósido Hidrolasas/metabolismo
10.
Clin Oral Implants Res ; 34(6): 555-564, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36847706

RESUMEN

BACKGROUND: While suggested to be effective in tissue regeneration, the effects of horizontal platelet-rich fibrin (H-PRF) bone block in sinus augmentation have not been verified in an animal model. METHODS: A total of 12 male New Zealand white rabbits that underwent sinus augmentation were divided into two groups: deproteinized bovine bone mineral (DBBM) only and H-PRF bone block. H-PRF was prepared at 700 × g for 8 min using a horizontal centrifuge. The H-PRF bone block was prepared by mixing 0.1 g DBBM with H-PRF fragments and then adding liquid H-PRF. Samples were collected after 4 and 8 weeks and analyzed using microcomputed tomography (micro-CT) for vertical bone gain of the sinus, bone volume/total volume (BV/TV) percentage, trabecular number (Tb.N), trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp). Then, histological analyses were performed to investigate new blood vessels, material residue, bone formation and osteoclasts. RESULTS: Higher vertical bone gain of the sinus floor, BV/TV percentage, Tb.Th, and Tb.N and lower Tb.Sp were found in the H-PRF bone block group at both time points compared with the DBBM group. Higher amounts of new blood vessels and more osteoclasts were found in the H-PRF bone block group than in the DBBM group at both time points, especially in the regions close to the bone plate. More new bone formation and less material residue were observed in the H-PRF bone block group at 8 weeks. CONCLUSIONS: H-PRF bone block showed greater potential for sinus augmentation by promoting angiogenesis, bone formation and bone remodeling in a rabbit model.


Asunto(s)
Sustitutos de Huesos , Fibrina Rica en Plaquetas , Elevación del Piso del Seno Maxilar , Masculino , Animales , Bovinos , Conejos , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Elevación del Piso del Seno Maxilar/métodos , Microtomografía por Rayos X , Sustitutos de Huesos/farmacología , Sustitutos de Huesos/uso terapéutico , Regeneración Ósea
11.
Front Microbiol ; 13: 1035791, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36523822

RESUMEN

Excessive use of chemical fertilizers to meet the global food demand has caused extensive environmental pollution. Microalgae can be used to enhance agricultural crop production as a potentially sustainable and eco-friendly alternative. In this study, Chlamydomonas applanata M9V and Chlorella vulgaris S3 were isolated from the soil and mass-cultured for use as microalgal fertilizers. The influence of microalgae M9V and S3 on the growth of wheat (Triticum aestivum L.) and soil properties was evaluated and compared with that of chemical urea fertilizer. A pot experiment was conducted with six treatments, i.e., living M9V (M9VL), dead M9V (M9VD), living S3 (S3L), dead S3 (S3D), urea fertilizer (urea), and control without fertilizer (control). M9VL was found to have the best effect on wheat growth promotion, followed by M9VD and S3D. In addition, M9VL resulted in the highest enhancement of shoot fresh weight (166.67 and 125.68%), root dry weight (188.89 and 77.35%), leaf length (26.88 and 14.56%), root length (46.04 and 43.93%), chlorophyll a (257.81 and 82.23%), and chlorophyll b contents (269.00 and 247.27%) comparing to the control and urea treatments, respectively. Moreover, all microalgal fertilizer treatments increased soil organic matter (SOM) by 1.77-23.10%, total carbon (TC) by 7.14-14.46%, and C:N ratio by 2.99-11.73% compared to the control and urea treatments. Overall, this study provided two microalgae strains, M9V and S3, that could promote wheat growth and improve soil properties, thus highlighting the use of microalgae as biofertilizers to reduce the use of chemical fertilizers and promoting sustainable agricultural production.

12.
Angew Chem Int Ed Engl ; 61(49): e202206802, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36224515

RESUMEN

Core fucosylation, the attachment of α1,6-fucose to the innermost N-acetylglucosamine (GlcNAc) residue of N-glycans, has a strong relationship with tumor growth, invasion, metastasis, prognosis, and immune evasion by regulating many membrane proteins. However, details about the functional mechanism are still largely unknown due to the lack of an effective analytical method to identify cell-surface core-fucosylated glycoproteins, and especially glycosylation sites. Here, we developed a sensitive and reversible labeling strategy for probing core fucosylation, by which core-fucosylated glycoproteins that located on cell-surface were selectively tagged by a biotinylated probe with high sensitivity. The labeled probe can be further broken enzymatically after the capture by affinity resin. The on-bead traceless cleavage allowed the global mapping of core-fucosylated glycoproteins and glycosylation sites by mass spectrometry (MS). The profile of core-fucosylated glycoproteome provides an in-depth understanding of the biological functions of core fucosylation.


Asunto(s)
Fucosa , Glicoproteínas , Glicosilación , Fucosa/química , Glicoproteínas/química , Espectrometría de Masas/métodos , Acetilglucosamina/química , Polisacáridos/química , Proteoma/metabolismo
13.
Curr Zool ; 68(4): 401-409, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36090144

RESUMEN

Studies on positional behavior and canopy use are essential for understanding how arboreal animals adapt their morphological characteristics and behaviors to the challenges of their environment. This study explores canopy and substrate use along with positional behavior in adult black snub-nosed monkeys Rhinopithecus strykeri, an endemic, critically endangered primate species in Gaoligong Mountains, southwest China. Using continuous focal animal sampling, we collected data over a 52-month period and found that R. strykeri is highly arboreal primarily using the high layers of the forest canopy (15-30 m), along with the terminal zone of tree crowns (52.9%), medium substrates (41.5%), and oblique substrates (56.8%). We also found sex differences in canopy and substrate use. Females use the terminal zones (56.7% versus 40.4%), small/medium (77.7% versus 60.1%), and oblique (59.9% versus 46.5%) substrates significantly more than males. On the other hand, males spend more time on large/very large (39.9% versus 22.3%) and horizontal (49.7% versus 35.2%) substrates. Whereas both sexes mainly sit (84.7%), and stand quadrupedally (9.1%), males stand quadrupedally (11.5% versus 8.3%), and bipedally (2.9% versus 0.8%) more often than females. Clamber, quadrupedalism, and leap/drop are the main locomotor modes for both sexes. Rhinopithecus strykeri populations never enter canopies of degenerated secondary forest and mainly use terminal branches in the middle and upper layers of canopies in intact mid-montane moist evergreen broadleaf forest and hemlock coniferous broadleaf mixed forests across their habitat.

14.
Am J Primatol ; 84(6): e23372, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35262940

RESUMEN

Traditionally, the genus Rhinopithecus (Milne-Edwards, 1872, Primates, Colobinae) included four allopatric species, restricted in their distributions to China and Vietnam. In 2010, a fifth species, the black snub-nosed monkey (Rhinopithecus strykeri) was discovered in the Gaoligong Mountains located on the border between China and Myanmar. Despite the remoteness, complex mountainous terrain, dense fog, and armed conflict that characterizes this region, over this past decade Chinese and Myanmar scientists have begun to collect quantitative data on the ecology, behavior and conservation requirements of R. strykeri. In this article, we review the existing data and present new information on the life history, ecology, and population size of R. strykeri. We discuss these data in the context of past and current conservation challenges faced by R. strykeri, and propose a series of both short-term and long-term management actions to ensure the survival of this Critically Endangered primate species. Specifically, we recommend that the governments and stakeholders in China and Myanmar formulate a transboundary conservation agreement that includes a consensus on bilateral exchange mechanisms, scientific research and monitoring goals, local community development, cooperation to prevent the hunting of endangered species and cross-border forest fires. These actions will contribute to the long-term conservation and survival of this Critically Endangered species.


Asunto(s)
Colobinae , Presbytini , Animales , Aniversarios y Eventos Especiales , China , Especies en Peligro de Extinción , Densidad de Población
15.
J Am Chem Soc ; 144(10): 4289-4293, 2022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35138101

RESUMEN

O-linked N-acetylglucosamine (O-GlcNAc) is a prevalent protein modification that plays fundamental roles in both cell physiology and pathology. O-GlcNAc is catalyzed solely by O-GlcNAc transferase (OGT). The study of protein O-GlcNAc function is limited by the lack of tools to control OGT activity with spatiotemporal resolution in cells. Here, we report light control of OGT activity in cells by replacing a catalytically essential lysine residue with a genetically encoded photocaged lysine. This enables the expression of a transiently inactivated form of OGT, which can be rapidly reactivated by photo-decaging. We demonstrate the activation of OGT activity by monitoring the time-dependent increase of cellular O-GlcNAc and profile glycoproteins using mass-spectrometry-based quantitative proteomics. We further apply this activation strategy to control the morphological contraction of fibroblasts. Furthermore, we achieved spatial activation of OGT activity predominantly in the cytosol. Thus, our approach provides a valuable chemical tool to control cellular O-GlcNAc with much needed spatiotemporal precision, which aids in a better understanding of O-GlcNAc function.


Asunto(s)
Lisina , N-Acetilglucosaminiltransferasas , Acetilglucosamina/metabolismo , Glicoproteínas/metabolismo , Lisina/metabolismo , N-Acetilglucosaminiltransferasas/metabolismo , Procesamiento Proteico-Postraduccional , Proteómica
16.
Biomater Sci ; 10(7): 1765-1775, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35212326

RESUMEN

Bone tissue engineering shows great potential in bone regeneration; however, the lack of bone growth factors with high biocompatibility and efficiency is a major concern. Oligopeptides have drawn great attention due to their high biological efficacy, low toxicity, and low molecular weight. The oligopeptide SDSSD promotes the osteogenesis of human periodontal ligament stem cells (hPDLSCs) in vitro. The SDSSD-modified three-dimensional (3D) bioscaffolds promote osteogenesis and bone formation in the subcutaneous pockets of BALB/c nude mice and facilitate bone healing in vivo. Mechanistically, SDSSD promoted bone formation by binding to G protein-coupled receptors and regulating the AKT signaling pathway. 3D-printing bioscaffolds with SDSSD may be potential bone tissue engineering materials for treating bone defects.


Asunto(s)
Osteogénesis , Ligamento Periodontal , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Ratones , Ratones Desnudos , Osteogénesis/fisiología , Péptidos/metabolismo , Péptidos/farmacología , Células Madre/metabolismo
17.
Angew Chem Int Ed Engl ; 60(50): 26128-26135, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34590401

RESUMEN

O-linked N-acetylglucosamine (O-GlcNAcylation) is a ubiquitous post-translational modification of proteins that is essential for cell function. Perturbation of O-GlcNAcylation leads to altered cell-cycle progression and DNA damage response. However, the underlying mechanisms are poorly understood. Here, we develop a highly sensitive one-step enzymatic strategy for capture and profiling O-GlcNAcylated proteins in cells. Using this strategy, we discover that flap endonuclease 1 (FEN1), an essential enzyme in DNA synthesis, is a novel substrate for O-GlcNAcylation. FEN1 O-GlcNAcylation is dynamically regulated during the cell cycle. O-GlcNAcylation at the serine 352 of FEN1 disrupts its interaction with Proliferating Cell Nuclear Antigen (PCNA) at the replication foci, and leads to altered cell cycle, defects in DNA replication, accumulation of DNA damage, and enhanced sensitivity to DNA damage agents. Thus, our study provides a sensitive method for profiling O-GlcNAcylated proteins, and reveals an unknown mechanism of O-GlcNAcylation in regulating cell cycle progression and DNA damage response.


Asunto(s)
Acetilglucosamina/metabolismo , ADN/metabolismo , Endonucleasas de ADN Solapado/metabolismo , Acetilglucosamina/química , Ciclo Celular , ADN/química , Daño del ADN , Endonucleasas de ADN Solapado/química , Glicosilación , Humanos
18.
Ecol Evol ; 11(1): 390-401, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33437437

RESUMEN

Ancient DNA research has developed rapidly over the past few decades due to improvements in PCR and next-generation sequencing (NGS) technologies, but challenges still exist. One major challenge in relation to ancient DNA research is to recover genuine endogenous ancient DNA sequences from raw sequencing data. This is often difficult due to degradation of ancient DNA and high levels of contamination, especially homologous contamination that has extremely similar genetic background with that of the real ancient DNA. In this study, we collected whole-genome sequencing (WGS) data from 6 ancient samples to compare different mapping algorithms. To further explore more effective methods to separate endogenous DNA from homologous contaminations, we attempted to recover reads based on ancient DNA specific characteristics of deamination, depurination, and DNA fragmentation with different parameters. We propose a quick and improved pipeline for separating endogenous ancient DNA while simultaneously decreasing homologous contaminations to very low proportions. Our goal in this research was to develop useful recommendations for ancient DNA mapping and for separation of endogenous DNA to facilitate future studies of ancient DNA.

19.
Front Microbiol ; 12: 768203, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35087484

RESUMEN

Globally soil salinity is one of the most devastating environmental stresses affecting agricultural systems and causes huge economic losses each year. High soil salinity causes osmotic stress, nutritional imbalance and ion toxicity to plants and severely affects crop productivity in farming systems. Freezing saline water irrigation and plastic mulching techniques were successfully developed in our previous study to desalinize costal saline soil. Understanding how microbial communities respond during saline soil amelioration is crucial, given the key roles soil microbes play in ecosystem succession. In the present study, the community composition, diversity, assembly and potential ecological functions of archaea, bacteria and fungi in coastal saline soil under amelioration practices of freezing saline water irrigation, plastic mulching and the combination of freezing saline water irrigation and plastic mulching were assessed through high-throughput sequencing. These amelioration practices decreased archaeal and increased bacterial richness while leaving fungal richness little changed in the surface soil. Functional prediction revealed that the amelioration practices, especially winter irrigation with saline water and film mulched in spring, promoted a community harboring heterotrophic features. ß-null deviation analysis illustrated that amelioration practices weakened the deterministic processes in structuring coastal saline soil microbial communities. These results advanced our understanding of the responses of the soil microbiome to amelioration practices and provided useful information for developing microbe-based remediation approaches in coastal saline soils.

20.
J Biomed Mater Res A ; 109(7): 1209-1219, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33021062

RESUMEN

Bone tissue plays an important role in supporting and protecting the structure and function of the human body. Bone defects are a common source of injury and there are many reconstruction challenges in clinical practice. However, 3D bioprinting of scaffolds provides a promising solution. Hydrogels have emerged as biomaterials with good biocompatibility and are now widely used as cell-loaded materials for bioprinting. This study involved three steps: First, sodium alginate (SA), gelatin (Gel), and nano-hydroxyapatite (na-HA) were mixed into a hydrogel and its rheological properties assessed to identify the optimum slurry for printing. Second, SA/Gel/na-HA bioscaffolds were printed using 3D bioprinting technology and their physical properties characterized for surface morphology, swelling, and mechanical properties. Finally, human periodontal ligament stem cells (hPDLSCs) were mixed with SA/Gel/na-HA printing slurry to create a "bioink" to prepare SA/Gel/na-HA/ hPDLSCs cell bioscaffolds. These were tested for biocompatibility and osteogenic differentiation performance using live/dead cell staining, cell adhesion, cell proliferation, and alkaline phosphatase activity. The SA/Gel/na-HA hydrogel exhibited shear-thinning behavior. The equilibrium swelling of the bioscaffold was 125.9%, the compression stress was 0.671 MPa, and the compression elastic modulus was 8.27 MPa. The SA/Gel/na-HA/hPDLSCs cell bioscaffolds caused effective stimulation of cell survival, proliferation, and osteoblast differentiation. Therefore, the SA/Gel/na-HA/hPDLSCs cell bioscaffolds displayed potential as a material for bone defect reconstruction.


Asunto(s)
Alginatos/química , Bioimpresión/métodos , Hidrogeles/química , Ligamento Periodontal/citología , Células Madre/citología , Andamios del Tejido/química , Células Cultivadas , Durapatita/química , Gelatina/química , Humanos , Osteogénesis , Impresión Tridimensional , Ingeniería de Tejidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA