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1.
Plant Cell ; 34(12): 4857-4876, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36053201

RESUMO

In multicellular eukaryotes, autophagy is a conserved process that delivers cellular components to the vacuole or lysosome for recycling during development and stress responses. Induction of autophagy activates AUTOPHAGY-RELATED PROTEIN 1 (ATG1) and ATG13 to form a protein kinase complex that initiates autophagosome formation. However, the detailed molecular mechanism underlying the regulation of this protein complex in plants remains unclear. Here, we determined that in Arabidopsis thaliana, the regulatory proteins 14-3-3λ and 14-3-3κ redundantly modulate autophagy dynamics by facilitating SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA (SINAT)-mediated proteolysis of ATG13a and ATG13b. 14-3-3λ and 14-3-3κ directly interacted with SINATs and ATG13a/b in vitro and in vivo. Compared to wild-type (WT), the 14-3-3λ 14-3-3κ double mutant showed increased tolerance to nutrient starvation, delayed leaf senescence, and enhanced starvation-induced autophagic vesicles. Moreover, 14-3-3s were required for SINAT1-mediated ubiquitination and degradation of ATG13a. Consistent with their roles in ATG degradation, the 14-3-3λ 14-3-3κ double mutant accumulated higher levels of ATG1a/b/c and ATG13a/b than the WT upon nutrient deprivation. Furthermore, the specific association of 14-3-3s with phosphorylated ATG13a was crucial for ATG13a stability and formation of the ATG1-ATG13 complex. Thus, our findings demonstrate that 14-3-3λ and 14-3-3κ function as molecular adaptors to regulate autophagy by modulating the homeostasis of phosphorylated ATG13.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Autofagia/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
2.
Plant Cell ; 34(2): 889-909, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34850198

RESUMO

Phosphatidic acid (PA) is an important lipid essential for several aspects of plant development and biotic and abiotic stress responses. We previously suggested that submergence induces PA accumulation in Arabidopsis thaliana; however, the molecular mechanism underlying PA-mediated regulation of submergence-induced hypoxia signaling remains unknown. Here, we showed that in Arabidopsis, loss of the phospholipase D (PLD) proteins PLDα1 and PLDδ leads to hypersensitivity to hypoxia, but increased tolerance to submergence. This enhanced tolerance is likely due to improvement of PA-mediated membrane integrity. PA bound to the mitogen-activated protein kinase 3 (MPK3) and MPK6 in vitro and contributed to hypoxia-induced phosphorylation of MPK3 and MPK6 in vivo. Moreover, mpk3 and mpk6 mutants were more sensitive to hypoxia and submergence stress compared with wild type, and fully suppressed the submergence-tolerant phenotypes of pldα1 and pldδ mutants. MPK3 and MPK6 interacted with and phosphorylated RELATED TO AP2.12, a master transcription factor in the hypoxia signaling pathway, and modulated its activity. In addition, MPK3 and MPK6 formed a regulatory feedback loop with PLDα1 and/or PLDδ to regulate PLD stability and submergence-induced PA production. Thus, our findings demonstrate that PA modulates plant tolerance to submergence via both membrane integrity and MPK3/6-mediated hypoxia signaling in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ácidos Fosfatídicos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Hipóxia , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Fenótipo , Fosfolipase D/genética , Fosfolipase D/metabolismo , Plantas Geneticamente Modificadas , Estabilidade Proteica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Inorg Chem ; 63(8): 3870-3881, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38356223

RESUMO

Metal-organic frameworks (MOFs) have shown promising potential as proton-conducting materials due to their tunable structures and high porosity. In this study, two novel MOFs had been successfully synthesized, one containing sulfate groups (MOF-1; [Zn4(TIPE)2(SO4)4(H2O)]·5H2O) and the other containing sulfonate groups (MOF-2; [Zn2(TIPE)(5-sip)(NO3)0.66]·0.34NO3·17.5H2O) (TIPE = 1,1,2,2-tetrakis(4-(1H-imidazole-1-yl)phenyl)ethene, H35-sip = 5-sulfoisophthalicacid), and the effect of the two groups on the proton conductivity of Zn-based MOFs had been investigated and compared for the first time. The proton conductivity of these MOFs was systematically measured at different temperatures and humidity conditions. Remarkably, the results revealed significant differences in proton conductivity between the two sets of MOFs. At 90 °C and 98% RH, MOF-1 and MOF-2 achieved optimal proton conductivity of 4.48 × 10-3 and 5.69 × 10-2 S·cm-1, respectively. This was due to the structural differences arising from the presence of different functional groups, which subsequently affected the porosity and hydrophilicity, thereby influencing the proton conductivity. Overall, this comparative study revealed the influence of sulfate and sulfonate groups on the proton conductivity of Zn-based MOFs. This research provided a feasible idea for the development of advanced MOF materials with enhanced proton conductivity and opened up new possibilities for their application in proton devices.

4.
Mol Divers ; 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240951

RESUMO

Akt1, as an important member of the Akt family, plays a controlled role in cancer cell growth and survival. Inhibition of Akt1 activity can promote cancer cell apoptosis and inhibit tumor growth. Therefore, in this investigation, a multilayer virtual screening approach, including receptor-ligand interaction-based pharmacophore, 3D-QSAR, molecular docking, and deep learning methods, was utilized to construct a virtual screening platform for Akt1 inhibitors. 17 representative compounds with different scaffolds were identified as potential Akt1 inhibitors from three databases. Among these 17 compounds, the Hit9 exhibited the best inhibitory activity against Akt1 with inhibition rate of 33.08% at concentration of 1 µM. The molecular dynamics simulations revealed that Hit9 and Akt1 could form a compact and stable complex. Moreover, Hit9 interacted with some key residues by hydrophobic, electrostatic, and hydrogen bonding interactions and induced substantial conformation changes in the hinge region of the Akt1 active site. The average binding free energies for the Akt1-CQU, Akt1-Ipatasertib, and Akt1-Hit9 systems were - 34.44, - 63.37, and - 39.14 kJ mol-1, respectively. In summary, the results obtained in this investigation suggested that Hit9 with novel scaffold may be a promising lead compound for developing new Akt1 inhibitor for treatment of various cancers with Akt1 overexpressed.

5.
Small ; 19(48): e2303802, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37519121

RESUMO

The volume expansion of CoFe2 O4 anode poses a significant challenge in the commercial application of lithium/sodium-ion batteries (LIBs/SIBs). However, metal-organic-frameworks (MOF) offer superior construction of heterostructures with refined interfacial interactions and lower ion diffusion barriers in Li/Na storage. In this study, the CoFe2 O4 @carbon nanofibers derived from MOF are produced through electrospinning, in situ growth followed by calcination, which are then confined within an MXene-confined MOF-derived porous CoFe2 O4 @carbon composite architecture under alkali treatment. The CoFe2 O4 nanofibers anchor on the alkalized MXene that is decorated with the NaOH solution to form a multi-pleated structure. The sandwich-like structure of the composite effectively alleviates the volume expansion and shortens the Li/Na-ion diffusion path, which displays high capacity and outstanding rate performance as anode materials for LIBs/SIBs. As a consequence, the obtained CoFe2 O4 @carbon@alkalized MXene composite anode shows satisfied rate performance at current density of 10 A g-1 for LIBs (318 mAh·g-1 ) and 5 A g-1 for SIBs (149 mAh g-1 ). The excellent cycling performance is further demonstrated at a high current density, where it maintains a discharge capacity of 807 mAh g-1 at 2 A g-1 after 400 cycles for LIBs and 130 mAh g-1 at 1 A g-1 even after 1000 cycles for SIBs.

6.
New Phytol ; 237(6): 2238-2254, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36513604

RESUMO

Submergence is an abiotic stress that limits agricultural production world-wide. Plants sense oxygen levels during submergence and postsubmergence reoxygenation and modulate their responses. Increasing evidence suggests that completely submerged plants are often exposed to low-light stress, owing to the depth and turbidity of the surrounding water; however, how light availability affects submergence tolerance remains largely unknown. Here, we showed that Arabidopsis thaliana MYB DOMAIN PROTEIN30 (MYB30) is an important transcription factor that integrates light signaling and postsubmergence stress responses. MYB DOMAIN PROTEIN30 protein abundance decreased upon submergence and accumulated during reoxygenation. Under submergence conditions, CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1), a central regulator of light signaling, caused the ubiquitination and degradation of MYB30. In response to desubmergence, however, light-induced MYB30 interacted with MYC2, a master transcription factor involved in jasmonate signaling, and activated the expression of the VITAMIN C DEFECTIVE1 (VTC1) and GLUTATHIONE SYNTHETASE1 (GSH1) gene families to enhance antioxidant biosynthesis. Consistent with this, the myb30 knockout mutant showed increased sensitivity to submergence, which was partially rescued by overexpression of VTC1 or GSH1. Thus, our findings uncover the mechanism by which the COP1-MYB30 module integrates light signals with cellular oxidative homeostasis to coordinate plant responses to postsubmergence stress.


Assuntos
Arabidopsis , Estresse Fisiológico , Fatores de Transcrição , Antioxidantes/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Ascórbico , Regulação da Expressão Gênica de Plantas , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Fenômenos Fisiológicos Vegetais , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Plant Cell ; 32(1): 263-284, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31732704

RESUMO

In eukaryotes, autophagy maintains cellular homeostasis by recycling cytoplasmic components. The autophagy-related proteins (ATGs) ATG1 and ATG13 form a protein kinase complex that regulates autophagosome formation; however, mechanisms regulating ATG1 and ATG13 remain poorly understood. Here, we show that, under different nutrient conditions, the RING-type E3 ligases SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA1 (SINAT1), SINAT2, and SINAT6 control ATG1 and ATG13 stability and autophagy dynamics by modulating ATG13 ubiquitylation in Arabidopsis (Arabidopsis thaliana). During prolonged starvation and recovery, ATG1 and ATG13 were degraded through the 26S proteasome pathway. TUMOR NECROSIS FACTOR RECEPTOR ASSOCIATED FACTOR1a (TRAF1a) and TRAF1b interacted in planta with ATG13a and ATG13b and required SINAT1 and SINAT2 to ubiquitylate and degrade ATG13s in vivo. Moreover, lysines K607 and K609 of ATG13a protein contributed to K48-linked ubiquitylation and destabilization, and suppression of autophagy. Under starvation conditions, SINAT6 competitively interacted with ATG13 and induced autophagosome biogenesis. Furthermore, under starvation conditions, ATG1 promoted TRAF1a protein stability in vivo, suggesting feedback regulation of autophagy. Consistent with ATGs functioning in autophagy, the atg1a atg1b atg1c triple knockout mutants exhibited premature leaf senescence, hypersensitivity to nutrient starvation, and reduction in TRAF1a stability. Therefore, these findings demonstrate that SINAT family proteins facilitate ATG13 ubiquitylation and stability and thus regulate autophagy.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Autofagia/fisiologia , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte/metabolismo , Proteínas de Membrana , Proteínas Mitocondriais , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
8.
Plant Cell ; 32(10): 3290-3310, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32753431

RESUMO

In plants, the ubiquitin-proteasome system, endosomal sorting, and autophagy are essential for protein degradation; however, their interplay remains poorly understood. Here, we show that four Arabidopsis (Arabidopsis thaliana) E3 ubiquitin ligases, SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA1 (SINAT1), SINAT2, SINAT3, and SINAT4, regulate the stabilities of FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING1 (FREE1) and VACUOLAR PROTEIN SORTING23A (VPS23A), key components of the endosomal sorting complex required for transport-I, to modulate abscisic acid (ABA) signaling. GFP-SINAT1, GFP-SINAT2, and GFP-SINAT4 primarily localized to the endosomal and autophagic vesicles. SINATs controlled FREE1 and VPS23A ubiquitination and proteasomal degradation. SINAT overexpressors showed increased ABA sensitivity, ABA-responsive gene expression, and PYRABACTIN RESISTANCE1-LIKE4 protein levels. Furthermore, the SINAT-FREE1/VPS23A proteins were codegraded by the vacuolar pathway. In particular, during recovery post-ABA exposure, SINATs formed homo- and hetero-oligomers in vivo, which were disrupted by the autophagy machinery. Taken together, our findings reveal a novel mechanism by which the proteasomal and vacuolar turnover systems regulate ABA signaling in plants.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Autofagia , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas/métodos , Plantas Geneticamente Modificadas , Mapas de Interação de Proteínas/fisiologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Vacúolos/metabolismo , Proteínas de Transporte Vesicular/genética
9.
Hum Genomics ; 16(1): 41, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123719

RESUMO

BACKGROUND: Heterotaxy syndrome (HTX) is caused by aberrant left-right patterning early in embryonic development, which results in abnormal positioning and morphology of the thoracic and abdominal organs. Currently, genetic testing discerns the underlying genetic cause in less than 20% of sporadic HTX cases, indicating that genetic pathogenesis remains poorly understood. In this study, we aim to garner a deeper understanding of the genetic factors of this disease by documenting the effect of different matrix metalloproteinase 21 (MMP21) variants on disease occurrence and pathogenesis. METHODS: Eighty-one HTX patients with complex congenital heart defects and 89 healthy children were enrolled, and we investigated the pathogenetic variants related to patients with HTX by exome sequencing. Zebrafish splice-blocking Morpholino oligo-mediated transient suppression assays were performed to confirm the potential pathogenicity of missense variants found in these patients with HTX. RESULTS: Three MMP21 heterozygous non-synonymous variants (c.731G > A (p.G244E), c.829C > T (p.L277F), and c.1459A > G (p.K487E)) were identified in three unrelated Chinese Han patients with HTX and complex congenital heart defects. Sanger sequencing confirmed that all variants were de novo. Cell transfection assay showed that none of the variants affect mRNA and protein expression levels of MMP21. Knockdown expression of mmp21 by splice-blocking Morpholino oligo in zebrafish embryos revealed a heart looping disorder, and mutant human MMP21 mRNA (c.731G > A, c.1459A > G, heterozygous mRNA (wild-type&c.731G > A), as well as heterozygous mRNA (wild-type& c.1459A > G) could not effectively rescue the heart looping defects. A patient with the MMP21 p.G244E variant was identified with other potential HTX-causing missense mutations, whereas the patient with the MMP21 p.K487E variant had no genetic mutations in other causative genes related to HTX. CONCLUSION: Our study highlights the role of the disruptive heterozygous MMP21 variant (p.K487E) in the etiology of HTX with complex cardiac malformations and expands the current mutation spectrum of MMP21 in HTX.


Assuntos
Síndrome de Heterotaxia , Animais , Criança , China , Síndrome de Heterotaxia/genética , Humanos , Morfolinos , RNA Mensageiro , Fatores de Risco , Peixe-Zebra/genética
10.
Langmuir ; 39(38): 13688-13694, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37683112

RESUMO

In this work, a "fish cage" material for trapping Pb(II) ions has been successfully obtained, which is a novel clathrate functionalized metal-oganic framework (Cage-MOF) by introducing free adsorption sites (SO42-). The three-dimensional (3D) cage structure of Cage-MOF gives it a larger contact area and can capture "swimming fish" (Pb(II)) like a "fishing cage" in a water solution. This is the first high-efficiency adsorption material obtained by introducing free coordination groups. Cage-MOF not only has excellent water stability but also improves the selectivity and affinity for Pb(II) ions in water because of the presence of sulfate adsorption sites, and its adsorption capacity is as high as 806 mg/g. This work shows a novel and effective idea for the synthesis of water restoration materials.

11.
Mol Med ; 28(1): 112, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100884

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) have emerged as regulators of human malignancies, including ovarian cancer (OC). LncRNA KCNQ1OT1 could promote OC progression, and EIF2B5 was associated with development of several tumors. This project was aimed to explore the role of lncRNA KCNQ1OT1 in OC development, as well as the involving action mechanism. METHODS: Reverse transcription quantitative polymerase chain reaction (RT-qPCR) or Western blotting was employed to determine the expression levels of KCNQ1OT1 and EIF2B5. OC cell proliferation was evaluated by MTT and colony formation assays, and wound healing and Transwell assays were implemented to monitor cell migration and invasion, respectively. The methylation status of EIF2B5 promoter was examined by MS-PCR, to clarify whether the expression of EIF2B5 was decreased. The binding activity of KCNQ1OT1 to methyltransferases DNMT1, DNMT3A and DNMT3B was determined by dual luciferase reporter assay or RIP assay, to explore the potential of KCNQ1OT1 alters the expression of its downstream gene. ChIP assay was carried out to verify the combination between EIF2B5 promoter and above three methyltransferases. RESULTS: Expression of lncRNA KCNQ1OT1 was increased in OC tissues and cells. EIF2B5 expression was downregulated in OC, which was inversely correlated with KCNQ1OT1. Knockdown of KCNQ1OT1 inhibited OC cell proliferation and metastasis. KCNQ1OT1 could downregulate EIF2B5 expression by recruiting DNA methyltransferases into EIF2B5 promoter. Furthermore, interference of EIF2B5 expression rescued KCNQ1OT1 depletion-induced inhibitory impact on OC cell proliferation and metastasis. CONCLUSION: Our findings evidenced that lncRNA KCNQ1OT1 aggravated ovarian cancer metastasis by decreasing EIF2B5 expression level, and provided a novel therapeutic strategy for OC.


Assuntos
MicroRNAs , Neoplasias Ovarianas , RNA Longo não Codificante , Carcinoma Epitelial do Ovário , Fator de Iniciação 2B em Eucariotos/metabolismo , Feminino , Humanos , Metilação , Metiltransferases/metabolismo , MicroRNAs/genética , Processos Neoplásicos , Neoplasias Ovarianas/patologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Regiões Promotoras Genéticas , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
12.
Rheumatology (Oxford) ; 61(9): 3704-3710, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34940809

RESUMO

OBJECTIVE: Rapidly progressive interstitial lung disease (RP-ILD) in DM patients positive for anti-melanoma differentiation-associated gene 5 (anti-MDA5) autoantibody (MDA5-DM) often have a poor prognosis, frequently fatal. As there is a scarcity of data regarding the effect of intravenous immunoglobulin (IVIG) on RP-ILD in MDA5-DM patients (MDA5-RPILD), we conducted this study to determine the efficacy of a IVIG add-on initial treatment. METHODS: Patients with newly-onset MDA5-RPILD from September 2018 to June 2020 were retrospectively reviewed for 6 months in the First Affiliated Hospital of Zhengzhou University. They were divided into two groups: IVIG and non-IVIG groups. The major measurement of treatment outcome was the difference in the mortality in 3-month and 6-month between two group patients. Other relevant indicators were also recorded, including the incidence of infection, the dosages of GCs, the remission rate and the variables in laboratory data. RESULTS: The IVIG group (n = 31) showed significantly lower 6-month mortality rate than the non-IVIG group (n = 17) (22.6% vs 52.9%; P =0.033). The IVIG group patients had a higher remission rate at 3 months (71.0% vs 41.2%; P =0.044). Gradual reduction was observed in the first 3 months with regard to the titre of anti-MDA5 autoantibody, the serum level of ferritin and the ground glass opacification GGO scores. CONCLUSION: IVIG adjunct therapy is a very effective first-line treatment for patients with MDA5-RPILD. IVIG may increase the survival and remission rate by lowering ferritin concentration, anti-MDA5 titre and GGO score.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Autoanticorpos , Dermatomiosite/complicações , Ferritinas , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Prognóstico , Estudos Retrospectivos
13.
Chemistry ; 28(60): e202203105, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36253120

RESUMO

Invited for the cover of this issue are the groups of Lin Du and Qi-Hua Zhao at Yunnan University. The image depicts astronauts as protons moving along the hydrogen-bond network in the channel of Eu-ETTB/Gd-ETTB. Read the full text of the article at 10.1002/chem.202202154.

14.
Chemistry ; 28(60): e202202154, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36048743

RESUMO

In this work, the two example rare earth-based metal-organic frameworks (LaIII -based MOFs), Eu-ETTB and Gd-ETTB, were obtained by self-assembly. Both materials showed extremely high proton conductivity, with the proton conductivity of Eu-ETTB being 1.53×10-2  S cm-1 at 98 % relative humidity (RH) and 85 °C and that of Gd-ETTB being 2.63×10-2  S cm-1 at 98 % RH and 75 °C. This was almost the best performance observed for three-dimensional porous MOFs without post-synthetic modification and was based on milder conditions than for most materials. Furthermore, cycle test experiments and continuous work tests showed that both materials had excellent performance both in terms of stability and durability. Water vapor adsorption experiments showed that a large number of water molecules are adsorbed the hydrogen-bond network's being rebuilt by the adsorbed water molecules in the pore channel and thus optimizing the channels for proton transfer explained the MOF's high performance.

15.
Inorg Chem ; 61(45): 18044-18058, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36315939

RESUMO

The recognition and adsorption of silver ions (Ag+) from industrial wastewater are necessary but still challenging. Herein, we constructed four Zn(II)-based coordination polymers (CPs), namely, [Zn(btap)2(NO3)2]n (1), [Zn(btap)(SO4)(H2O)3]n (2), {[Zn(btap)2(H2O)2]·(ClO4)2}n (3), and [Zn(btap)Cl2]n (4), by using 3,5-bis(triazol-1-yl)pyridine (btap) with different anionic Zn(II) salts. The crystal structures of 1-4, varying from one-dimensional beaded (1) and zigzag chain (2) to two-dimensional sql (3) and bex (4) typologies, were regulated by the coordination modes of btap and the counter-anions. The water stability, pH stability, thermostability, and luminescent properties of the CPs were investigated. The luminescence performances in a series of cations and anions were also explored. Considering the high density of chloride groups in the structure, 4 showed luminescence sensing for Ag+ [KSV = 9188.45 M-1 and a limit of detection (LOD) of 4.9 µM], as well as an excellent ability for Ag+ adsorption in aqueous solution (maximum adsorption capacity, 653.3 mg/g). Additionally, anti-interference experiments revealed that 4 had excellent recognition and adsorption capacities for Ag+ even when multiple ions coexisted. Moreover, XRD, EDS, and XPS analyses confirmed that the coordination of Ag+ with chloride groups in 4 resulted in excellent adsorption capacity and prevented ligand-to-ligand electron transfer, showing excellent detection ability. Suitable coordination sites were introduced to interact strongly with Ag+, along with detection and large adsorption capacity. Our strategy can effectively design and develop multifunctional CP-based materials, which are applicable in removal processes and environmental protection, by regulating anions in the self-assembly and introducing CP functional groups.


Assuntos
Polímeros , Prata , Prata/química , Polímeros/química , Ligantes , Adsorção , Cloretos , Ânions/química , Água/química
16.
Bioorg Chem ; 122: 105722, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35303622

RESUMO

Disruption of the dynamic equilibrium of microtubules can induce cell cycle arrest in G2/M phase and apoptosis. Hence, discovery of novel tubulin polymerization inhibitors is very necessary and an important task in drug research and development for treatment of various tumors. In this investigation, 50 compounds were screened as microtubule stabilizers targeting the taxane site by combination of molecular docking methods. Among these hits, hits 19 and 38 with novel scaffolds exhibited the highest anti-proliferative activity with IC50 ranging from 9.50 to 13.81 µM in four cancer cell lines. The molecular dynamics simulations confirmed that tubulin and two hits could form stable systems. Meanwhile, the mechanism of the interactions between tubulin and two hits at simulated physiological conditions were probed. The in vitro tubulin polymerization assay revealed hits 19 and 38 were able to promote tubulin polymerization in a dose-dependent manner. Further, the immunofluorescence assay suggested that hits 19 and 38 could accelerate microtubule assembly in A549 and HeLa cells. Finally, studies on antitumor activity indicated that hits 19 and 38 induced G2/M phase cell cycle arrest and apoptosis, and inhibited cancer cell motility and migration in A549 and HeLa cells. Importantly, hit38 exhibited better anti-tubulin and anti-cancer activity than hit19 in A549 and HeLa cells. Therefore, these results suggest that hit38 represents a promising microtubule stabilizer for treating cancer and deserves further investigation.


Assuntos
Antineoplásicos , Simulação de Dinâmica Molecular , Antineoplásicos/química , Sítios de Ligação , Hidrocarbonetos Aromáticos com Pontes , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Microtúbulos/metabolismo , Simulação de Acoplamento Molecular , Taxoides , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/química
17.
J Comput Assist Tomogr ; 46(2): 300-307, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35081600

RESUMO

BACKGROUND: The distinction between solitary inflammatory lesion and solitary lung cancer remains a challenge because of their considerable overlapping computed tomography (CT) imaging features. PURPOSE: This study aimed to verify whether spectral CT parameters can differentiate solitary lung cancer from solitary inflammatory lesions and to find their correlations with lesion size. METHODS: A total of 78 patients with solitary lung lesions were included in our study. All of them underwent enhanced CT scans with Gemstone Spectral Imaging (GSI) mode, which was one of the dual-energy imaging technologies. According to maximum diameter (Dmax) of the lesion, regions of interest were collected and divided into inflammatory (group I: <3 cm [IA], n = 17; ≥3 cm [IB], n = 14) and cancer groups (group II: <3 cm [IIA], n = 20; ≥3 cm [IIB], n = 27). Computed tomography values (HU40keV, HU70keV), effective atomic number (Zeff), iodine concentration (IC), normalized IC (NIC), and spectral curve slopes (λ30, λ40) of each region of interest were calculated. The NIC was defined as the IC ratio of the lesion to the descending aorta. Mann-Whitney U test was used for intergroup (I vs II, IA vs IIA, IB vs IIB) and intragroup (IA vs IB, IIA vs IIB) comparisons, and receiver operating characteristic curve analysis was performed. Correlation analysis was applied to find the relationship between Dmax and GSI parameters. RESULTS: No significant correlation was found between GSI parameters and Dmax in the inflammatory group, whereas inverse correlations were found in the cancer group. Gemstone spectral imaging parameters (except HU70keV) of group IIA were significantly higher than those of group IIB. There were significant differences in HU40keV, IC, NIC, λ30, and λ40 between groups IB and IIB under both arterial and venous phase (P values < 0.05), whereas the area under the curve for λ30 under venous phase was largest, and sensitivity and specificity were 96.32% and 85.71%, respectively. However, only HU40keV and HU70keV values under the arterial phase of IIA were significantly higher than those of IA. CONCLUSIONS: Quantitative parameters of GSI demonstrated an inverse correlation with the lesion size of solitary lung cancer, and GSI parameters can be new ways to differentiate solitary lung cancer from solitary inflammatory lesions.


Assuntos
Iodo , Neoplasias Pulmonares , Pneumonia , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia Computadorizada por Raios X/métodos
18.
Int J Mol Sci ; 23(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35955763

RESUMO

Serum and glucocorticoid-regulated kinase 1 (SGK1), as a serine threonine protein kinase of the AGC family, regulates different enzymes, transcription factors, ion channels, transporters, and cell proliferation and apoptosis. Inhibition of SGK1 is considered as a valuable approach for the treatment of various metabolic diseases. In this investigation, virtual screening methods, including pharmacophore models, Bayesian classifiers, and molecular docking, were combined to discover novel inhibitors of SGK1 from the database with 29,158 compounds. Then, the screened compounds were subjected to ADME/T, PAINS and drug-likeness analysis. Finally, 28 compounds with potential inhibition activity against SGK1 were selected for biological evaluation. The kinase inhibition activity test revealed that among these 28 hits, hit15 exhibited the highest inhibition activity against SGK1, which gave 44.79% inhibition rate at the concentration of 10 µM. In order to further investigate the interaction mechanism of hit15 and SGK1 at simulated physiological conditions, a molecular dynamics simulation was performed. The molecular dynamics simulation demonstrated that hit15 could bind to the active site of SGK1 and form stable interactions with key residues, such as Tyr178, ILE179, and VAL112. The binding free energy of the SGK1-hit15 was -48.90 kJ mol-1. Therefore, the identified hit15 with novel scaffold may be a promising lead compound for development of new SGK1 inhibitors for various diseases treatment.


Assuntos
Simulação de Dinâmica Molecular , Proteínas Serina-Treonina Quinases , Teorema de Bayes , Ligantes , Simulação de Acoplamento Molecular
19.
J Sci Food Agric ; 102(10): 4200-4209, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35018645

RESUMO

BACKGROUND: Because many common foods are emulsions (mayonnaise, margarine, salad dressing, etc.), a better understanding of lipid oxidation is crucial for the formulation, production, and storage of the relevant consumer products. We prepared oil-in-water (O/W) and water-in-oil (W/O) emulgels, and their architecture was characterized before monitoring lipid oxidation under thermally accelerated conditions to systematically compare the effect of emulsion type, oil composition, and oil fraction on the structure and lipid oxidation in thee biphasic emulgel systems. RESULTS: Higher susceptibility of lipids to oxidation (>2.5 times) was observed in the biphasic O/W and W/O emulgels than in soybean oil owing to an interfacial region. In the heterogeneous emulsion systems, W/O emulgels had oxidation resistance than O/W emulgels did. Compared with the oil-phase composition of high oleic sunflower, soybean, and flaxseed oils, oxidation sensitivity of emulsified lipids was significantly raised as the degree of unsaturation increased from 100.72 to 203.07. Moreover, increasing oil fraction from 75% to 85% led to an obvious increase in total oxidation in O/W emulgels but a decrease in W/O emulgels. In addition to emulsion size and oil unsaturation, viscoelasticity had a remarkable effect on the low-unsaturated oil oxidation (e.g. high oleic sunflower oil). CONCLUSION: Physical and structural phenomena played important roles in lipid oxidation based on a mass transport principle. These findings provide novel information for designing the structures of emulsion gels for controlling lipid oxidation through the cooperation of both formulation and architecture principles. © 2022 Society of Chemical Industry.


Assuntos
Óleos , Água , Emulsões/química , Géis/química , Óleos/química , Viscosidade , Água/química
20.
J Integr Plant Biol ; 64(2): 431-448, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34676666

RESUMO

Tumor necrosis factor receptor-associated factor (TRAF) proteins are conserved in higher eukaryotes and play key roles in transducing cellular signals across different organelles. They are characterized by their C-terminal region (TRAF-C domain) containing seven to eight anti-parallel ß-sheets, also known as the meprin and TRAF-C homology (MATH) domain. Over the past few decades, significant progress has been made toward understanding the diverse roles of TRAF proteins in mammals and plants. Compared to other eukaryotic species, the Arabidopsis thaliana and rice (Oryza sativa) genomes encode many more TRAF/MATH domain-containing proteins; these plant proteins cluster into five classes: TRAF/MATH-only, MATH-BPM, MATH-UBP (ubiquitin protease), Seven in absentia (SINA), and MATH-Filament and MATH-PEARLI-4 proteins, suggesting parallel evolution of TRAF proteins in plants. Increasing evidence now indicates that plant TRAF proteins form central signaling networks essential for multiple biological processes, such as vegetative and reproductive development, autophagosome formation, plant immunity, symbiosis, phytohormone signaling, and abiotic stress responses. Here, we summarize recent advances and highlight future prospects for understanding on the molecular mechanisms by which TRAF proteins act in plant development and stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fenômenos Biológicos , Animais , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Mamíferos/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo
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