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1.
Mol Cell ; 84(16): 3011-3025.e7, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39116874

RESUMO

The histone variant macroH2A is generally linked to transcriptionally inactive chromatin, but how macroH2A regulates chromatin structure and functions in the transcriptional process remains elusive. This study reveals that while the integration of human macroH2A1.2 into nucleosomes does not affect their stability or folding dynamics, it notably hinders the maintenance of facilitates chromatin transcription's (FACT's) function. We show that FACT effectively diminishes the stability of macroH2A1.2-nucleosomes and expedites their depletion subsequent to the initial unfolding process. Furthermore, we identify the residue S139 in macroH2A1.2 as a critical switch to modulate FACT's function in nucleosome maintenance. Genome-wide analyses demonstrate that FACT-mediated depletion of macroH2A-nucleosomes allows the correct localization of macroH2A, while the S139 mutation reshapes macroH2A distribution and influences stimulation-induced transcription and cellular response in macrophages. Our findings provide mechanistic insights into the intricate interplay between macroH2A and FACT at the nucleosome level and elucidate their collective role in transcriptional regulation and immune response of macrophages.


Assuntos
Histonas , Nucleossomos , Transcrição Gênica , Fatores de Elongação da Transcrição , Humanos , Nucleossomos/metabolismo , Nucleossomos/genética , Histonas/metabolismo , Histonas/genética , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Proteínas de Grupo de Alta Mobilidade/genética , Animais , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Macrófagos/metabolismo , Mutação , Montagem e Desmontagem da Cromatina , Camundongos , Cromatina/metabolismo , Cromatina/genética , Regulação da Expressão Gênica , Células RAW 264.7 , Ligação Proteica , Células HEK293
2.
Mol Cell ; 71(2): 284-293.e4, 2018 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-30029006

RESUMO

The human FACT (facilitates chromatin transcription) complex, composed of two subunits SPT16 (Suppressor of Ty 16) and SSRP1 (Structure-specific recognition protein-1), plays essential roles in nucleosome remodeling. However, the molecular mechanism of FACT reorganizing the nucleosome still remains elusive. In this study, we demonstrate that FACT displays dual functions in destabilizing the nucleosome and maintaining the original histones and nucleosome integrity at the single-nucleosome level. We found that the subunit SSRP1 is responsible for maintenance of nucleosome integrity by holding the H3/H4 tetramer on DNA and promoting the deposition of the H2A/H2B dimer onto the nucleosome. In contrast, the large subunit SPT16 destabilizes the nucleosome structure by displacing the H2A/H2B dimers. Our findings provide mechanistic insights by which the two subunits of FACT coordinate with each other to fulfill its functions and suggest that FACT may play essential roles in preserving the original histones with epigenetic identity during transcription or DNA replication.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Nucleossomos/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , DNA/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Grupo de Alta Mobilidade/genética , Histonas/metabolismo , Humanos , Modelos Moleculares , Nucleossomos/genética , Ligação Proteica , Multimerização Proteica , Proteínas de Saccharomyces cerevisiae/metabolismo , Células Sf9 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/genética
3.
Proc Natl Acad Sci U S A ; 120(13): e2221874120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36947515

RESUMO

Cyclic-di-GMP (c-di-GMP) is a ubiquitous bacterial signaling molecule. It is also a critical player in the regulation of cell size and cell behaviors such as cell aggregation and phototaxis in cyanobacteria, which constitute an important group of prokaryotes for their roles in the ecology and evolution of the Earth. However, c-di-GMP receptors have never been revealed in cyanobacteria. Here, we report the identification of a c-di-GMP receptor, CdgR, from the filamentous cyanobacterium Anabaena PCC 7120. Crystal structural analysis and genetic studies demonstrate that CdgR binds c-di-GMP at the dimer interface and this binding is required for the control of cell size in a c-di-GMP-dependent manner. Different functions of CdgR, in ligand binding and signal transmission, could be separated genetically, allowing us to dissect its molecular signaling functions. The presence of the apo-form of CdgR triggers cell size reduction, consistent with the similar effects observed with a decrease of c-di-GMP levels in cells. Furthermore, we found that CdgR exerts its function by interacting with a global transcription factor DevH, and this interaction was inhibited by c-di-GMP. The lethal effect triggered by conditional depletion of DevH or by the production of several point-mutant proteins of CdgR in cells indicates that this signaling pathway plays critical functions in Anabaena. Our studies revealed a mechanism of c-di-GMP signaling in the control of cell size, an important and complex trait for bacteria. CdgR is highly conserved in cyanobacteria, which will greatly expand our understanding of the roles of c-di-GMP signaling in these organisms.


Assuntos
Cianobactérias , Transdução de Sinais , Cianobactérias/metabolismo , GMP Cíclico/metabolismo , Regulação da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
4.
Gut ; 73(2): 350-360, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37949638

RESUMO

OBJECTIVE: The gut virome is a dense community of viruses inhabiting the gastrointestinal tract and an integral part of the microbiota. The virome coexists with the other components of the microbiota and with the host in a dynamic equilibrium, serving as a key contributor to the maintenance of intestinal homeostasis and functions. However, this equilibrium can be interrupted in certain pathological states, including inflammatory bowel disease, causing dysbiosis that may participate in disease pathogenesis. Nevertheless, whether virome dysbiosis is a causal or bystander event requires further clarification. DESIGN: This review seeks to summarise the latest advancements in the study of the gut virome, highlighting its cross-talk with the mucosal microenvironment. It explores how cutting-edge technologies may build upon current knowledge to advance research in this field. An overview of virome transplantation in diseased gastrointestinal tracts is provided along with insights into the development of innovative virome-based therapeutics to improve clinical management. RESULTS: Gut virome dysbiosis, primarily driven by the expansion of Caudovirales, has been shown to impact intestinal immunity and barrier functions, influencing overall intestinal homeostasis. Although emerging innovative technologies still need further implementation, they display the unprecedented potential to better characterise virome composition and delineate its role in intestinal diseases. CONCLUSIONS: The field of gut virome is progressively expanding, thanks to the advancements of sequencing technologies and bioinformatic pipelines. These have contributed to a better understanding of how virome dysbiosis is linked to intestinal disease pathogenesis and how the modulation of virome composition may help the clinical intervention to ameliorate gut disease management.


Assuntos
Doenças Inflamatórias Intestinais , Microbiota , Vírus , Humanos , Viroma , Disbiose , Doenças Inflamatórias Intestinais/terapia
5.
Anal Chem ; 96(29): 11682-11689, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38979688

RESUMO

Cell death is a fundamental biological process with different modes including apoptosis and necrosis. In contrast to programmed apoptosis, necrosis was previously considered disordered and passive, but it is now being realized to be under regulation by certain biological pathways. However, the intracellular dynamics that coordinates with cellular structure changes during necrosis remains unknown, limiting our understanding of the principles of necrosis. Here, we characterized the spatiotemporal intracellular diffusion dynamics in cells undergoing necrosis, using three-dimensional single-particle tracking of quantum dots. We found temporally increased diffusion rates in necrotic cells and spatially enhanced diffusion heterogeneity in the cell periphery, which could be attributed to the reduced molecular crowding resulting from cell swelling and peripheral blebbing, respectively. Moreover, the three-dimensional intracellular diffusion transits from strong anisotropy to nearly isotropy, suggesting a remodeling of the cytoarchitecture that relieves the axial constraint on intracellular diffusion during necrosis. Our results reveal the remarkable alterations of intracellular diffusion dynamics and biophysical properties in necrosis, providing insight into the well-organized nonequilibrium necrotic cell death from a biophysical perspective.


Assuntos
Necrose , Pontos Quânticos , Pontos Quânticos/química , Humanos , Difusão , Células HeLa
6.
J Transl Med ; 22(1): 156, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360704

RESUMO

PURPOSES: Radiotherapy can induce tumor cell autophagy, which might impair the antitumoral effect. This study aims to investigate the effect of autophagy inhibition on the targeted radionuclide therapy (TRT) efficacy of 131I-FAP-2286 in pancreatic cancer. METHODS: Human pancreatic cancer PANC-1 cells were exposed to 131I-FAP-2286 radiotherapy alone or with the autophagy inhibitor 3-MA. The autophagy level and proliferative activity of PANC-1 cells were analyzed. The pancreatic cancer xenograft-bearing nude mice were established by the co-injection of PANC-1 cells and pancreatic cancer-associated fibroblasts (CAFs), and then were randomly divided into four groups and treated with saline (control group), 3-MA, 131I-FAP-2286 and 131I-FAP-2286 + 3-MA, respectively. SPECT/CT imaging was performed to evaluate the bio-distribution of 131I-FAP-2286 in pancreatic cancer-bearing mice. The therapeutic effect of tumor was evaluated by 18F-FDG PET/CT imaging, tumor volume measurements, and the hematoxylin and eosin (H&E) staining, and immunohistochemical staining assay of tumor tissues. RESULTS: 131I-FAP-2286 inhibited proliferation and increased the autophagy level of PANC-1 cells in a dose-dependent manner. 3-MA promoted 131I-FAP-2286-induced apoptosis of PANC-1 cells via suppressing autophagy. SPECT/CT imaging of pancreatic cancer xenograft-bearing nude mice showed that 131I-FAP-2286 can target the tumor effectively. According to 18F-FDG PET/CT imaging, the tumor growth curves and immunohistochemical analysis, 131I-FAP-2286 TRT was capable of suppressing the growth of pancreatic tumor accompanying with autophagy induction, but the addition of 3-MA enabled 131I-FAP-2286 to achieve a better therapeutic effect along with the autophagy inhibition. In addition, 3-MA alone did not inhibit tumor growth. CONCLUSIONS: 131I-FAP-2286 exposure induces the protective autophagy of pancreatic cancer cells, and the application of autophagy inhibitor is capable of enhancing the TRT therapeutic effect.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Autofagia , Linhagem Celular Tumoral , Camundongos Nus , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radioisótopos/farmacologia , Radioisótopos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Acta Pharmacol Sin ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227736

RESUMO

Emerging evidence shows that psychological stress promotes the progression of Parkinson's disease (PD) and the onset of dyskinesia in non-PD individuals, highlighting a potential avenue for therapeutic intervention. We previously reported that chronic restraint-induced psychological stress precipitated the onset of parkinsonism in 10-month-old transgenic mice expressing mutant human α-synuclein (αSyn) (hαSyn A53T). We refer to these as chronic stress-genetic susceptibility (CSGS) PD model mice. In this study we investigated whether ginsenoside Rg1, a principal compound in ginseng notable for soothing the mind, could alleviate PD deterioration induced by psychological stress. Ten-month-old transgenic hαSyn A53T mice were subjected to 4 weeks' restraint stress to simulate chronic stress conditions that worsen PD, meanwhile the mice were treated with Rg1 (40 mg· kg-1 ·d-1, i.g.), and followed by functional magnetic resonance imaging (fMRI) and a variety of neurobehavioral tests. We showed that treatment with Rg1 significantly alleviated both motor and non-motor symptoms associated with PD. Functional MRI revealed that Rg1 treatment enhanced connectivity between brain regions implicated in PD, and in vivo multi-channel electrophysiological assay showed improvements in dyskinesia-related electrical activity. In addition, Rg1 treatment significantly attenuated the degeneration of dopaminergic neurons and reduced the pathological aggregation of αSyn in the striatum and SNc. We revealed that Rg1 treatment selectively reduced the level of the stress-sensitive protein RTP801 in SNc under chronic stress conditions, without impacting the acute stress response. HPLC-MS/MS analysis coupled with site-directed mutation showed that Rg1 promoted the ubiquitination and subsequent degradation of RTP801 at residues K188 and K218, a process mediated by the Parkin RING2 domain. Utilizing αSyn A53T+; RTP801-/- mice, we confirmed the critical role of RTP801 in stress-aggravated PD and its necessity for Rg1's protective effects. Moreover, Rg1 alleviated obstacles in αSyn autophagic degradation by ameliorating the RTP801-TXNIP-mediated deficiency of ATP13A2. Collectively, our results suggest that ginsenoside Rg1 holds promise as a therapeutic choice for treating PD-sensitive individuals who especially experience high levels of stress and self-imposed expectations.

8.
Acta Pharmacol Sin ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112771

RESUMO

Esculetin (ESC) is a coumarin-derived phytochemical prevalent in traditional Chinese medicine that exhibits anti-acute ischemic stroke activities. Our previous studies demonstrate that CKLF1 is a potential anti-stroke target for coumarin-derived compound. In this study we investigated whether CKLF1 was involved in the neuroprotective effects of ESC against photothrombotic stroke in mice. The mice were treated with ESC (20, 40 or 80 mg·kg-1·d-1, i.g.) for two weeks. The therapeutic effect of ESC was assessed using MRI, neurological function evaluation, and a range of behavioral tests on D1, 3, 7 and 14 of ESC administration. We showed that oral administration of ESC dose-dependently reduced the cerebral infarction volume within one week after stroke, improved behavioral performance, and alleviated neuropathological damage within two weeks. Functional MRI revealed that ESC significantly enhanced the abnormal low-frequency fluctuation (ALFF) value of the motor cortex and promoted functional connectivity between the supplementary motor area (SMA) and multiple brain regions. We demonstrated that ESC significantly reduced the protein levels of CKLF1 and CCR5, as well as the CKLF1/CCR5 protein complex in the peri-infarcted area. We showed that ESC (0.1-10 µM) dose-dependently blocked CKLF1-induced chemotactic movement of neutrophils in the Transwell assay, reducing the interaction of CKLF1/CCR5 on the surface of neutrophils, thereby reducing neutrophil infiltration, and decreasing the expression of ICAM-1, VCAM-1 and MMP-9 in the peri-infarct tissue. Knockout of CKLF1 reduced brain infarction volume and motor dysfunction after stroke but also negated the anti-stroke efficacy and neutrophil infiltration of ESC. These results suggest that the efficacy of ESC in promoting post-stroke neural repair depends on its inhibition on CKLF1-mediated neutrophil infiltration, which offering novel perspectives for elucidating the therapeutic properties of coumarins.

9.
Mol Cell ; 64(1): 120-133, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27666592

RESUMO

In eukaryotes, the packaging of genomic DNA into chromatin plays a critical role in gene regulation. However, the dynamic organization of chromatin fibers and its regulatory mechanisms remain poorly understood. Using single-molecule force spectroscopy, we reveal that the tetranucleosomes-on-a-string appears as a stable secondary structure during hierarchical organization of chromatin fibers. The stability of the tetranucleosomal unit is attenuated by histone chaperone FACT (facilitates chromatin transcription) in vitro. Consistent with in vitro observations, our genome-wide analysis further shows that FACT facilitates gene transcription by destabilizing the tetranucleosomal unit of chromatin fibers in yeast. Additionally, we found that the linker histone H1 not only enhances the stability but also facilitates the folding and unfolding kinetics of the outer nucleosomal wrap. Our study demonstrates that the tetranucleosome is a regulatory structural unit of chromatin fibers beyond the nucleosome and provides crucial mechanistic insights into the structure and dynamics of chromatin fibers during gene transcription.


Assuntos
DNA Fúngico/química , Proteínas de Ligação a DNA/química , Regulação Fúngica da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/química , Histonas/química , Nucleossomos/genética , Proteínas de Saccharomyces cerevisiae/química , Transcrição Gênica , Fatores de Elongação da Transcrição/química , Sequência de Aminoácidos , DNA Fúngico/genética , DNA Fúngico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Histonas/genética , Histonas/metabolismo , Modelos Moleculares , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Dobramento de Proteína , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Imagem Individual de Molécula , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
10.
Nucleic Acids Res ; 50(2): 833-846, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-34951461

RESUMO

The histone chaperone FACT (FAcilitates Chromatin Transcription) plays an essential role in transcription and DNA replication by its dual functions on nucleosome assembly to maintain chromatin integrity and nucleosome disassembly to destabilize nucleosome and facilitate its accessibility simultaneously. Mono-ubiquitination at Lysine 119 of H2A (ubH2A) has been suggested to repress transcription by preventing the recruitment of FACT at early elongation process. However, up to date, how ubH2A directly affects FACT on nucleosome assembly and disassembly remains elusive. In this study, we demonstrated that the dual functions of FACT are differently regulated by ubH2A. The H2A ubiquitination does not affect FACT's chaperone function in nucleosome assembly and FACT can deposit ubH2A-H2B dimer on tetrasome to form intact nucleosome. However, ubH2A greatly restricts FACT binding on nucleosome and inhibits its activity of nucleosome disassembly. Interestingly, deubiquitination of ubH2A rescues the nucleosome disassembly function of FACT to activate gene transcription. Our findings provide mechanistic insights of how H2A ubiquitination affects FACT in breaking nucleosome and maintaining its integrity, which sheds light on the biological function of ubH2A and various FACT's activity under different chromatin states.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Animais , Linhagem Celular , Montagem e Desmontagem da Cromatina , Camundongos , Ligação Proteica , Ubiquitinação
11.
BMC Musculoskelet Disord ; 25(1): 81, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245679

RESUMO

BACKGROUND: Symptomatic lumbar disc herniation (LDH) and lumbar isthmic spondylolisthesis (LIS) present significant challenges for military pilots, which may result in grounding if not effectively managed. Surgical treatment for LDH and LIS may offer a pathway to return to flight duty (RTFD), but recent data on this crucial topic is lacking. This study seeks to address this gap by investigating the RTFD outcomes among Chinese military pilots who have undergone lumbar spine surgery for symptomatic LDH and LIS. METHODS: A retrospective review was conducted on active-duty military pilots who underwent isolated decompressive or fusion procedures at an authorized military medical center from March 1, 2007, to March 1, 2023. The analysis utilized descriptive statistics to examine demographic, occupational, surgical, and outcome data, with a particular focus on preoperative flight status, recommended clearance by spine surgeons, and actual RTFD outcomes and time. RESULTS: Among the identified cases of active-duty military pilots with LDH or LIS treated by lumbar surgery (n = 24), 70.8% (17 of 24) consistently maintained RTFD status without encountering surgical complications or medical issues during the follow-up period. Of the seven pilots who did not RTFD, one retired within a year of surgery, two had anterior cruciate ligament injuries, three had residual radicular symptoms, and one had chronic low back pain. Excluding pilots who retired and did not RTFD for reasons unrelated to their lumbar conditions, the RTFD rate stood at 81.0% (17 of 21). The median time for recommended clearance by spine surgeons was 143.0 days (inter-quartile range, 116.5-196.0), while the median duration for actual RTFD attainment was 221.0 days (inter-quartile range, 182.0-300.0). The median follow-up post-lumbar surgery was 1.7 years (inter-quartile range, 0.4-2.9). CONCLUSION: Most military pilots diagnosed with symptomatic LDH and LIS can continue their careers and regain active-duty flight status following lumbar spine surgery, as reflected by the high RTFD rate. Lumbar spine surgery can successfully alleviate the physical constraints associated with spinal conditions, facilitating the return of military pilots to their demanding profession.


Assuntos
Deslocamento do Disco Intervertebral , Militares , Fusão Vertebral , Espondilolistese , Humanos , Deslocamento do Disco Intervertebral/epidemiologia , Deslocamento do Disco Intervertebral/cirurgia , Espondilolistese/epidemiologia , Espondilolistese/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Vértebras Lombares/cirurgia , China/epidemiologia , Fusão Vertebral/métodos
12.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255916

RESUMO

Chicoric acid (CA) has been reported to exhibit biological activities; it remains unclear, however, whether CA could regulate colitis via modulation of the gut microbiota and metabolites. This study aimed to assess CA's impact on dextran sulfate sodium (DSS)-induced colitis, the gut microbiota, and metabolites. Mice were induced with 2.5% DSS to develop colitis over a 7-day period. CA was administered intragastrically one week prior to DSS treatment and continued for 14 days. The microbial composition in the stool was determined using 16S rRNA sequencing, while non-targeted metabolomics was employed to analyze the metabolic profiles of each mouse group. The results show that CA effectively alleviated colitis, as evidenced by an increased colon length, lowered disease activity index (DAI) and histological scores, and decreased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) expression levels. CA intervention restored the structure of gut microbiota. Specifically, it decreased the abundance of Bacteroidetes and Cyanobacteria at the phylum level and Bacteroides, Rosiarcus, and unclassified Xanthobacteraceae at the genus level, and increased the abundance of unclassified Lachnospiraceae at the genus level. Metabolomic analysis revealed that CA supplementation reversed the up-regulation of asymmetric dimethylarginine, N-glycolylneuraminic acid, and N-acetylneuraminic acid, as well as the down-regulation of phloroglucinol, thiamine, 4-methyl-5-thiazoleethanol, lithocholic acid, and oxymatrine induced by DSS. Our current research provides scientific evidence for developing CA into an anti-colitis functional food ingredient. Further clinical trials are warranted to elucidate the efficacy and mechanism of CA in treating human inflammatory bowel disease (IBD).


Assuntos
Ácidos Cafeicos , Colite , Microbioma Gastrointestinal , Succinatos , Humanos , Animais , Camundongos , Camundongos Endogâmicos BALB C , Sulfato de Dextrana/toxicidade , RNA Ribossômico 16S/genética , Colite/induzido quimicamente , Colite/tratamento farmacológico
13.
Int J Mol Sci ; 25(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000074

RESUMO

Chloroplasts is the site for photosynthesis, which is the main primary source of energy for plants. Golden2-like (GLK) is a key transcription factor that regulates chloroplast development and chlorophyll synthesis. However, most studies on GLK genes are performed in crops and model plants with less attention to woody plants. In this study, we identified the LhGLK1 and LhGLK2 genes in the woody plant Liriodendron hybrid, and they are specifically expressed in green tissues. We showed that overexpression of the LhGLK1 gene improves rosette leaf chlorophyll content and induces ectopic chlorophyll biogenesis in primary root and petal vascular tissue in Arabidopsis. Although these exhibit a late-flowering phenotype, transgenic lines accumulate more biomass in vegetative growth with improved photochemical quenching (qP) and efficiency of photosystem II. Taken together, we verified a conserved and ancient mechanism for regulating chloroplast biogenesis in Liriodendron hybrid and evaluated its effect on photosynthesis and rosette biomass accumulation in the model plant Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Clorofila , Regulação da Expressão Gênica de Plantas , Liriodendron , Fotossíntese , Plantas Geneticamente Modificadas , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Clorofila/metabolismo , Liriodendron/genética , Liriodendron/metabolismo , Fotossíntese/genética , Plantas Geneticamente Modificadas/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Cloroplastos/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento
14.
Anal Chem ; 95(13): 5594-5600, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36942711

RESUMO

As intelligent probes, dynamic and controllable molecular switches are useful tools for probing and intervening in life processes. However, the types and properties of molecular switches are still relatively single and often can only make two actions: "off" and "on". Therefore, the development of novel molecular switches with multiple colors and multiple instructions is very challenging. Herein, we propose a novel strategy based on the instability of the Lewis acid-base pair (boron (B) and nitrogen (N)), such as introducing the Schiff base (C═N) group into the aminoborane skeleton and preparing the novel molecular switches BN-HDZ and BN-HDZ-N. These two molecules were found to have good multicolor fluorescence switching capability for methanol. Surprisingly, the compound BN-HDZ-N shows unprecedented visual identification for the butanol isomers and could be made into a portable strip for simple and rapid visual identification of the four isomers of butanol, promising an alternative to conventional Lucas reagents. This provides a novel strategy for the design and fabrication of novel multicolor-tunable molecular switches with visual identification of isomers.

15.
BMC Plant Biol ; 23(1): 163, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973660

RESUMO

BACKGROUND: Cyanide is a toxic chemical that inhibits cellular respiration. In plants, cyanide can be produced by themselves, especially under stressful conditions. Cyanoalanine synthase (CAS) is a key enzyme involved in plant cyanide detoxification. There are three genes encoding CAS in Arabidopsis thaliana, but the roles of these genes in the plant's response to stress are less studied. In addition, it is known that alternative oxidase (AOX) mediates cyanide-resistant respiration, but the relationship between CAS and AOX in regulating the plant stress response remains largely unknown. RESULTS: Here, the effects of the overexpression or mutation of these three CAS genes on salt stress tolerance were investigated. The results showed that under normal conditions, the overexpression or mutation of the CAS genes had no significant effect on the seed germination and growth of Arabidopsis thaliana compared with wild type (WT). However, under 50, 100, and 200 mM NaCl conditions, the seeds overexpressing CAS genes showed stronger salt stress resistance, i.e., higher germination speed than WT seeds, especially those that overexpressed the CYS-C1 and CYS-D1 genes. In contrast, the seeds with CAS gene mutations exhibited salt sensitivity, and their germination ability and growth were significantly damaged by 100 and 200 mM NaCl. Importantly, this difference in salt stress resistance became more pronounced in CAS-OE, WT, and mutant seeds with increasing salt concentration. The CAS-OE seeds maintained higher respiration rates than the WT and CAS mutant seeds under salt stress conditions. The cyanide contents in CAS mutant seeds were approximately 3 times higher than those in WT seeds and more than 5 times higher than those in CAS-OE seeds. In comparison, plants overexpressing CYS-C1 had the fastest detoxification of cyanide and the best salt tolerance, followed by those overexpressing CYS-D1 and CYS-D2. Furthermore, less hydrogen sulfide (H2S) was observed in CAS-OE seedlings than in WT seedlings under long-term salt stress conditions. Nonetheless, the lack of AOX impaired CAS-OE-mediated plant salt stress resistance, suggesting that CAS and AOX interact to improve salt tolerance is essential. The results also showed that CAS and AOX contributed to the reduction in oxidative damage by helping maintain relatively high levels of antioxidant enzyme activity. CONCLUSION: In summary, the findings of the present study suggest that overexpression of Arabidopsis CAS family genes plays a positive role in salt stress tolerance and highlights the contribution of AOX to CAS-mediated plant salt resistance, mainly by reducing cyanide and H2S toxicity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Tolerância ao Sal , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cianetos/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação/genética , Óxido Nítrico Sintase/genética , Plantas Geneticamente Modificadas/genética , Tolerância ao Sal/genética , Cloreto de Sódio/farmacologia
16.
Crit Rev Food Sci Nutr ; : 1-11, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085004

RESUMO

Pulses have attracted much attention in the food industry due to their low cost, high yield, and high protein content, which promises to be excellent alternative protein sources. Recently, techniques for covalent and noncovalent binding of pulse proteins to polyphenols are expected to solve the problem of their poor protein functional properties. Additionally, these conjugates and complexes also show several health benefits. This review summarizes the formation of conjugates and complexes between pulse proteins and polyphenols through covalent and noncovalent binding and the impact of this structural change on protein functionalities and potential health benefits. Recent studies show that pulse protein functionalities can be influenced by polyphenol dose. This is mainly the case for adverse effects on solubility and enhancement in emulsifying capacity. Also, the conjugates/complexes exhibit antioxidant activity and can alter protein digestibility. The antioxidant activity of polyphenols could be retained after binding to proteins, while the effect on digestibility depends on the type or dosage of polyphenols. Considering the link between polyphenols and their potential health benefits, pulse polyphenols would be a good choice for producing the conjugates/complexes due to their low cost and proven potential benefits. Further studies on the structure-function-health benefits relationship of pulse protein-polyphenol conjugates and complexes are still required, as well as the validation of their application as functional foods in the food industry.

17.
Crit Rev Food Sci Nutr ; : 1-13, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37497995

RESUMO

Diabetes mellitus (DM) is a chronic metabolic disease caused by a complex interaction of genetic and environmental factors and is characterized by persistent hyperglycemia. Long-term hyperglycemia can cause macrovascular and microvascular damage, and compromise the heart, brain, kidney, peripheral nerves, eyes and other organs, leading to serious complications. Genistein, a phytoestrogen derived from soybean, is known for its various biological activities and therapeutic properties. Recent studies found that genistein not only has hypoglycemic activity but can also decrease insulin resistance. In addition, genistein has particular activity in the prevention and treatment of diabetic complications, such as nephropathy, cardiovascular disease, osteoarthrosis, encephalopathy and retinopathy. Therefore, the purpose of this review is to summarize the latest medical research and progress of genistein in DM and related complications and highlights its potential molecular mechanisms and therapeutic targets. Meanwhile, evidence is provided for the development and application of genistein as a potential drug or functional food in the prevention and treatment of diabetes and its related complications.

18.
Crit Rev Food Sci Nutr ; : 1-14, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287270

RESUMO

Osmanthus fragrans (O. fragrans) has been cultivated in China for over 2,500 years as a traditional fragrant plant. Recently, O. fragrans has drawn increasing attention due to its unique aroma and potential health benefits. In this review, the aroma and functional components of O. fragrans are summarized, and their biosynthetic mechanism is discussed. The beneficial functions and related molecular mechanism of O. fragrans extract are then highlighted. Finally, potential applications of O. fragrans are summarized, and future perspectives are proposed and discussed. According to the current research, O. fragrans extracts and components have great potential to be developed into value-added functional ingredients with preventive effects on certain chronic diseases. However, it is crucial to develop efficient, large-scale, and commercially viable extraction methods to obtain the bioactive components from O. fragrans. Furthermore, more clinical studies are highly needed to explore the beneficial functions of O. fragrans and guide its development into functional food products.

19.
Cell Mol Biol (Noisy-le-grand) ; 69(9): 89-99, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37807329

RESUMO

Cervical cancer (CC) is a growing health concern, emphasizing the need for reliable biomarkers in treatment selection and prognosis assessment. We analyzed gene expression profiles and clinicopathological data from The Cancer Genome Atlas (TCGA) for CC. Using Consensus Cluster Plus, we applied machine learning to cluster the CC cohort. Differential analysis was performed using the edge R package, while weighted correlation network analysis (WGCNA) was conducted using the WGCNA package. Single-sample gene set enrichment analysis (ssGSEA) evaluated immune cell abundance and computed the m6Ascore. Western blot and Q-PCR validated the m6A score in CC. Common copy number variation alterations were observed in the 23 m6A-related genes in CC, and their mutation frequency was summarized in a waterfall chart. Patients were grouped into two clusters, m6AclusterA and m6AclusterB. Improved clinical outcomes were observed in m6AclusterA, while m6AclusterB exhibited higher infiltration of 14 immune cell types. WGCNA analysis generated seven integrated modules, enriched in several biological processes. Prognostic differential genes were used to generate two gene clusters (gene Cluster I and gene Cluster II). Using ssGSEA, the m6Ascore was calculated for each patient. Lower m6Ascore correlated with better clinical outcomes, lower gene mutation frequency, and wild-type status. We investigated the sensitivity of high and low m6Ascore to immunotherapy, visualized through violin and UMAP diagrams showcasing crosstalk among single-cell clusters. The key gene PFKFB4 showed higher expression in CC cell lines and tumor tissues compared to normal cells and tissue. Our study elucidates the role of m6A molecules in predicting prognosis, biological features, and appropriate treatment for CC patients.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Prognóstico , Variações do Número de Cópias de DNA , Western Blotting , Linhagem Celular , Fosfofrutoquinase-2
20.
Oral Dis ; 29(4): 1657-1667, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35226761

RESUMO

OBJECTIVE: This study aimed to elucidate the underlying mechanisms of ameloblastoma (AM) through integrated bioinformatics analysis. METHODS: We downloaded two microarrays of AMs from the GEO database and identified differentially expressed genes (DEGs) by integrated bioinformatics analysis. The enrichment analysis of DEGs was conducted to characterize GO and KEGG pathways. Protein-protein interaction (PPI) network and hub genes were screened via STRING and Cytoscape. CIBERSORT algorithm was utilized to analyze immune infiltration in AMs. We also verified the diagnostic and therapeutic value of hub genes. RESULTS: Overall, 776 DEGs were identified in AMs through bioinformatics analysis. The function enrichment analysis shed light on pathways involved in AMs. Subsequently, we screened six hub genes via PPI network. Furthermore, we evaluated immune infiltration in AMs and found that macrophages may be participating in the progression of AMs. The upregulated expression of FN1 was related to the macrophages M2 polarization. Finally, ROC analysis indicated that six hub genes had high diagnostic value for AMs and 11 drugs interacted with upregulated hub genes were identified by screening the DGIdb database. CONCLUSION: This study revealed the underlying mechanisms of pathogenesis and biological behavior of AMs and provided candidate targets for the diagnosis and treatment of AMs.


Assuntos
Ameloblastoma , Humanos , Ameloblastoma/genética , Transição Epitelial-Mesenquimal/genética , Algoritmos , Biomarcadores , Biologia Computacional , Perfilação da Expressão Gênica
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