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1.
EMBO J ; 42(2): e111268, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36408830

RESUMO

Reprogramming of lipid metabolism is emerging as a hallmark of cancer, yet involvement of specific fatty acids (FA) species and related enzymes in tumorigenesis remains unclear. While previous studies have focused on involvement of long-chain fatty acids (LCFAs) including palmitate in cancer, little attention has been paid to the role of very long-chain fatty acids (VLCFAs). Here, we show that depletion of acetyl-CoA carboxylase (ACC1), a critical enzyme involved in the biosynthesis of fatty acids, inhibits both de novo synthesis and elongation of VLCFAs in human cancer cells. ACC1 depletion markedly reduces cellular VLCFA but only marginally influences LCFA levels, including palmitate that can be nutritionally available. Therefore, tumor growth is specifically susceptible to regulation of VLCFAs. We further demonstrate that VLCFA deficiency results in a significant decrease in ceramides as well as downstream glucosylceramides and sphingomyelins, which impairs mitochondrial morphology and renders cancer cells sensitive to oxidative stress and cell death. Taken together, our study highlights that VLCFAs are selectively required for cancer cell survival and reveals a potential strategy to suppress tumor growth.


Assuntos
Neoplasias , Estearatos , Humanos , Estearatos/metabolismo , Ácidos Graxos/metabolismo , Mitocôndrias/metabolismo , Palmitatos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
2.
Phytopathology ; 114(6): 1196-1205, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38281161

RESUMO

When Pseudomonas savastanoi pv. phaseolicola, the bacterium that causes halo blight, induces hypersensitive immunity in common bean leaves, salicylic acid and phytoalexins accumulate at the site of infection. Both salicylic acid and the phytoalexin resveratrol exert antibiotic activities and toxicities in vitro, adversely disrupting the P. savastanoi pv. phaseolicola proteome and metabolism and stalling replication and motility. These efficacious properties likely contribute to the cessation of bacterial spread in beans. Genistein is an isoflavonoid phytoalexin that also accumulates during bean immunity, so we tested its antibiotic potential in vitro. Quantitative proteomics revealed that genistein did not induce proteomic changes in P. savastanoi pv. phaseolicola in the same way that salicylic acid or resveratrol did. Rather, a dioxygenase that could function to metabolize genistein was among the most highly induced enzymes. Indeed, high-throughput metabolomics provided direct evidence for genistein catabolism. Metabolomics also revealed that genistein induced the bacterium to produce indole compounds, several of which had structural similarity to auxin. Additional mass spectrometry analyses proved that the bacterium produced an isomer of the auxin indole-3-acetic acid but not indole-3-acetic acid proper. These results reveal that P. savastanoi pv. phaseolicola can tolerate bean genistein and that the bacterium likely responds to bean-produced genistein during infection, using it as a signal to increase pathogenicity, possibly by altering host cell physiology or metabolism through the production of potential auxin mimics.


Assuntos
Genisteína , Fitoalexinas , Doenças das Plantas , Pseudomonas , Sesquiterpenos , Genisteína/farmacologia , Genisteína/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Pseudomonas/efeitos dos fármacos , Sesquiterpenos/metabolismo , Sesquiterpenos/farmacologia , Indóis/metabolismo , Indóis/farmacologia , Ácido Salicílico/metabolismo , Folhas de Planta/microbiologia , Phaseolus/microbiologia , Proteômica , Ácidos Indolacéticos/metabolismo , Estilbenos/metabolismo , Estilbenos/farmacologia , Resveratrol/farmacologia , Resveratrol/metabolismo
3.
Disasters ; : e12652, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119667

RESUMO

The COVID-19 (coronavirus disease 2019) pandemic initiated debates on how crisis management affects democracy. In them, the balance between deploying control strategies that limit citizens' freedom and their democratic legitimation features prominently. Informed by theoretical debates about responsive crisis governance, this paper explores how Chinese citizens reacted by quantitatively and qualitatively analysing social media expressions and Chinese stakeholders' narratives. The quantitative analysis indicated that public sentiments towards pandemic control were complex and mostly related to the severe pandemic in Wuhan. Negative sentiments were mainly directed at local states; national states largely received respect. The qualitative analysis exhibited more nuances. Although Chinese crisis governance raised efficiency and trust, aggressive accountability efforts and improper information exchange caused justice deficits and public anxiety. Draconian social control misaligned public interests and a lack of specific partnership mechanisms frustrated social participation. Reconciling institutional efficiency with civic liberties on diverse governance levels is thus expected to increase the responsiveness of pandemic control to public demands.

5.
J Proteome Res ; 20(7): 3664-3677, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34097416

RESUMO

Pseudomonas savastanoi pv. phaseolicola causes halo blight disease in the common bean Phaseolus vulgaris. The bacterium invades the leaf apoplast and uses a type III secretion system to inject effector proteins into a bean cell to interfere with the bean immune system. Beans counter with resistance proteins that can detect effectors and coordinate effector-triggered immunity responses transduced by salicylic acid, the primary defense hormone. Effector-triggered immunity halts bacterial spread, but its direct effect on the bacterium is not known. In this study, mass spectrometry of bacterial infections from immune and susceptible beans revealed that immune beans inhibited the accumulation of bacterial proteins required for virulence, secretion, motility, chemotaxis, quorum sensing, and alginate production. Sets of genes encoding these proteins appeared to function in operons, which implies that immunity altered the coregulated genes in the bacterium. Immunity also reduced amounts of bacterial methylglyoxal detoxification enzymes and their transcripts. Treatment of bacteria with salicylic acid, the plant hormone produced during immunity, reduced bacterial growth, decreased gene expression for methylglyoxal detoxification enzymes, and increased bacterial methylglyoxal concentrations in vitro. Increased methylglyoxal concentrations reduced bacterial reproduction. These findings support the hypothesis that plant immunity involves the chemical induction of adverse changes to the bacterial proteome to reduce pathogenicity and to cause bacterial self-toxicity.


Assuntos
Phaseolus , Pseudomonas syringae , Proteínas de Bactérias , Doenças das Plantas , Imunidade Vegetal , Pseudomonas , Virulência
6.
Phytopathology ; 111(5): 893-895, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33315475

RESUMO

Pseudomonas savastanoi pv. phaseolicola causes halo blight disease on Phaseolus vulgaris. Using a long-read DNA sequencing platform, we assembled the genome sequences for P. savastanoi pv. phaseolicola races 5 and 8 that have distinguishable avirulent and virulent phenotypes on Phaseolus vulgaris PI G19833, a common bean with an annotated genome sequence. The 12 race 5 assemblies comprise two major 4.5 and 1.4 Mb chromosome-like contigs and 10 smaller contigs. The four race 8 assemblies comprise a major 6.1 Mb chromosome and three smaller contigs. Annotation yielded 5,890 genes for race 5 and 5,919 genes for race 8. These data will enable the discovery of the genetic and proteomic differences between these two races and allow comparisons to other races for which genomic information already exists.


Assuntos
Phaseolus , Pseudomonas syringae , Genômica , Phaseolus/genética , Doenças das Plantas , Proteômica , Pseudomonas
7.
J Cell Biochem ; 120(10): 17779-17790, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31127646

RESUMO

The major cause of mortality for prostate cancer (PCa) is metastasis; however, the metastatic mechanism remains unclear. MicroRNAs (miRNAs) alter the expression patterns of essential genes through posttranscriptional regulation during cancer development. The study was mainly aimed at identifying specific miRNA-messenger RNA (mRNA) interactions and signaling pathways associated with PCa distant metastasis. New analytical approaches were applied, combining miRNA and gene expression microarray, to screen differentially expressed miRNA-mRNA pairs in the normal prostate epithelial cell line RWPE-1, the highly-metastatic human PCa cell line PC-3M-1E8 (H-1E8 or 1E8) and the lowly metastatic cell line PC-3M-2B4 (L-2B4 or 2B4). Eight differentially expressed candidate miRNAs and their targets closely related to PCa metastasis were identified and validated in patients by using the Gene Expression Omnibus database. Among them, overexpression of hsa-miR-92b-3p and hsa-let-7a-5p and underexpression of their targets, such as glutathione-S-transferase M3 (GSTM3), baculoviral IAP repeat-containing 3, and cyclin-dependent kinase inhibitor 1 (CDKN1A), were also validated in H-1E8 cells compared with L-2B4 cells. Bioinformatics suggested that hsa-miR-92b-3p and hsa-let-7a-5p and their targets might promote PCa metastasis through platinum-based drug resistance and the JAK-STAT signaling pathway. H-1E8 and L-2B4 cells treated by cisplatin showed the greatly decreased levels of hsa-miR-92b-3p and hsa-let-7a-5p; however, in contrast to 2B4 cells, 1E8 cells did not negatively regulate the increase in the expression levels of the targets GSTM3 and CDKN1A. This finding suggests that the dysregulation between hsa-let-7a-5p/CDKN1A and hsa-miR-92b-3p/GSTM3 pairs is associated with platinum-based chemoresistance of metastatic cancer cells.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/genética , Transdução de Sinais/genética , Animais , Linhagem Celular Tumoral , Cisplatino/farmacologia , Bases de Dados Genéticas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Modelos Biológicos , Metástase Neoplásica , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes
8.
J Exp Bot ; 69(12): 3009-3021, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29648636

RESUMO

INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) is a signaling peptide that regulates cell separation in Arabidopsis including floral organ abscission and lateral root emergence. IDA is highly conserved in dicotyledonous flowering plant genomes. IDA-like sequences were also found in the genomic sequences of root-knot nematodes, Meloidogyne spp., which are globally deleterious pathogens of agriculturally important plants, but the role of these genes is unknown. Exogenous treatment of the Arabidopsis ida mutant with synthetic peptide identical to the M. incognita IDA-like 1 (MiIDL1) protein sequence minus its N-terminal signal peptide recovered both the abscission and root architecture defects. Constitutive expression of the full-length MiIDL1 open reading frame in the ida mutant substantially recovered the delayed floral organ abscission phenotype whereas transformants expressing a construct missing the MiIDL1 signal peptide retained the delayed abscission phenotype. Importantly, wild-type Arabidopsis plants harboring an MiIDL1-RNAi construct and infected with nematodes had approximately 40% fewer galls per root than control plants. Thus, the MiIDL1 gene produces a functional IDA mimic that appears to play a role in successful gall development on Arabidopsis roots.


Assuntos
Proteínas de Arabidopsis/análise , Arabidopsis/parasitologia , Regulação da Expressão Gênica de Plantas , Proteínas de Helminto/genética , Doenças das Plantas/parasitologia , Tylenchida/fisiologia , Animais , Arabidopsis/genética , Proteínas de Helminto/metabolismo , Tylenchida/genética
9.
Mol Cell Biochem ; 424(1-2): 185-193, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27785703

RESUMO

Multiple myeloma (MM) remains incurable by conventional chemotherapy. Sphingosine-1-phosphate (S1P) receptor-mediated signaling has been recently demonstrated to have critical roles in cell survival and drug resistance in a number of hematological malignancies. To dissect the roles of S1P receptor pathway in MM, we systematically examined cell viability and protein expression associated with cell survival and drug resistance in MM cell lines upon treatment with either pathway activator (S1P) or inhibitor (FTY720). Our results reveal that FTY720 inhibits cell proliferation by downregulating expression of target genes, while S1P has an opposite effect. Knocking down of S1P receptor S1P5R results in a reduction of cell survival-related gene expression; however, it does not have impacts on expression of drug resistance genes. These results suggest that S1P signaling plays a role in cell proliferation and drug resistance in MM, and targeting this pathway will provide a new therapeutic direction for MM management.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Cloridrato de Fingolimode/farmacologia , Humanos , Masculino , Mieloma Múltiplo/patologia
10.
Healthcare (Basel) ; 12(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39201217

RESUMO

(1) Background: Playful immunization promotion helps to approach persuasive efforts and raise vaccine acceptance. However, playful promotion in the field of HPV immunization has not been explored. (2) Methods: To address this gap, we analyzed data gleaned from 73 short videos posted by state media and from semi-structured interviews with 37 Chinese stakeholders using thematic analysis. (3) Results: The analysis revealed that state media promoted HPV immunization using celebrity endorsement, anthropomorphism techniques and entertainment performance strategies. Additionally, state media engaged in circle mobilization and livestreamed on Douyin to reach wider audiences. Although playful strategies increased the popularity of HPV vaccine promotion, insufficient multi-stakeholder partnerships and homogeneous message delivery decreased the efficiency of HPV immunization promotion campaigns. (4) Conclusions: The strengthening of multi-stakeholder partnerships and the optimization of the public service provision of HPV vaccination are expected. Our research will not only deepen the global audience's understanding of Chinese immunization promotion campaigns, but also offer insights for implementing future global health promotion.

11.
Sci Rep ; 14(1): 4841, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418855

RESUMO

We used the Exploris 240 mass spectrometer for non-targeted metabolomics on Saccharomyces cerevisiae strain BY4741 and tested AcquireX software for increasing the number of detectable compounds and Compound Discoverer 3.3 software for identifying compounds by MS2 spectral library matching. AcquireX increased the number of potentially identifiable compounds by 50% through six iterations of MS2 acquisition. On the basis of high-scoring MS2 matches made by Compound Discoverer, there were 483 compounds putatively identified from nearly 8000 candidate spectra. Comparisons to 20 amino acid standards, however, revealed instances whereby compound matches could be incorrect despite strong scores. Situations included the candidate with the top score not being the correct compound, matching the same compound at two different chromatographic peaks, assigning the highest score to a library compound much heavier than the mass for the parent ion, and grouping MS2 isomers to a single parent ion. Because the software does not calculate false positive and false discovery rates at these multiple levels where such errors can propagate, we conclude that manual examination of findings will be required post software analysis. These results will interest scientists who may use this platform for metabolomics research in diverse disciplines including medical science, environmental science, and agriculture.


Assuntos
Metabolômica , Software , Metabolômica/métodos , Espectrometria de Massas/métodos , Padrões de Referência
12.
Nat Commun ; 15(1): 6915, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134530

RESUMO

Protein post-translational modifications (PTMs) are crucial for cancer cells to adapt to hypoxia; however, the functional significance of lysine crotonylation (Kcr) in hypoxia remains unclear. Herein we report a quantitative proteomics analysis of global crotonylome under normoxia and hypoxia, and demonstrate 128 Kcr site alterations across 101 proteins in MDA-MB231 cells. Specifically, we observe a significant decrease in K131cr, K156cr and K220cr of phosphoglycerate kinase 1 (PGK1) upon hypoxia. Enoyl-CoA hydratase 1 (ECHS1) is upregulated and interacts with PGK1, leading to the downregulation of PGK1 Kcr under hypoxia. Abolishment of PGK1 Kcr promotes glycolysis and suppresses mitochondrial pyruvate metabolism by activating pyruvate dehydrogenase kinase 1 (PDHK1). A low PGK1 K131cr level is correlated with malignancy and poor prognosis of breast cancer. Our findings show that PGK1 Kcr is a signal in coordinating glycolysis and the tricarboxylic acid (TCA) cycle and may serve as a diagnostic indicator for breast cancer.


Assuntos
Neoplasias da Mama , Ciclo do Ácido Cítrico , Glicólise , Fosfoglicerato Quinase , Fosfoglicerato Quinase/metabolismo , Fosfoglicerato Quinase/genética , Humanos , Glicólise/genética , Linhagem Celular Tumoral , Feminino , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Regulação para Baixo , Camundongos , Proteômica/métodos , Camundongos Nus , Regulação Neoplásica da Expressão Gênica , Mitocôndrias/metabolismo , Hipóxia Celular , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética
13.
Exp Parasitol ; 134(2): 165-70, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23538028

RESUMO

Small peptides play important roles in intercellular signaling. Inflorescence deficient in abscission (ida) is an Arabidopsis mutant that does not abscise (shed) its flower petals. The IDA gene encodes a small, secreted peptide that putatively binds to two redundant receptor-like kinases (HAESA and HAESA-like2) that initiate a signal transduction pathway. We identified IDA-like (IDL) genes in the genomic sequence for Meloidogyne incognita and Meloidogyne hapla. No orthologous sequences were found in any other genus of nematodes. Transcript for both M. incognita and M. hapla IDLs were found in total RNA isolated from infected root systems of tomato, Solanum lycopersicum. Five and three prime RACE of RNA from M. incognita infected tomato roots revealed a sequence of 392 nt that includes a poly (A) tail of 39 nt. The open reading frame encodes a 47 aa protein with a putative 25 aa N-terminal signal peptide. Expression of MiIDL1 is very low in eggs and pre-parasitic J2 and rapidly increases in the first four days post inoculation (dpi) and then declines at approximately 14 dpi. A proposed role for the root-knot nematode IDL is discussed.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Plantas/genética , Raízes de Plantas/parasitologia , Solanum lycopersicum/parasitologia , Tylenchoidea/genética , Sequência de Aminoácidos , Animais , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Capsicum/parasitologia , Regulação da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Solanum lycopersicum/crescimento & desenvolvimento , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Sinais Direcionadores de Proteínas/genética , RNA Mensageiro/metabolismo , RNA de Plantas/química , RNA de Plantas/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/metabolismo
14.
Risk Manag Healthc Policy ; 16: 2915-2929, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38164293

RESUMO

Background: COVID-19 vaccine promotion helps counter vaccine hesitancy and raise vaccine acceptance. Therefore, the Chinese state created collaborative infrastructures of COVID-19 vaccine promotion programs to promote stakeholder engagement and unload the burden of policy practitioners. However, partnerships in COVID-19 vaccine promotion programs have been underrepresented. Methods: To address this lacuna, we qualitatively explored how partnerships in the COVID-19 vaccine promotion campaign (CVPC) were organized in China's neighborhoods. Specifically, we recruited participants via personal networks, referrals from acquaintances, and snowballing approaches, and conducted the qualitative thematic analysis following interviews with 62 Chinese stakeholders. Results: This study indicates that to promote partnerships in CVPCs, neighborhood managers formed leadership in CVPCs, expanded the collaborative network, trained Health Promotion Practitioners (HPPs), and coordinated with HPPs to shape partnership agreements, produced COVID-19 vaccine promotional materials and advertised COVID-19 vaccines via diverse media tools. Although coproduction of CVPCs to a certain extent promoted state-society interaction in neighborhoods and state responsiveness to public demands, partners' disagreements on strategies applied by states for promoting COVID-19 vaccines eroded partnerships in CVPCs. Conclusion: To construct a robust partnership in CVPCs, depoliticizing CVPCs and creating shared values among stakeholders in CVPCs are expected. Our study will not only deepen global audiences' understanding of CVCPs in China but also offer potential neighborhood-level solutions for implementing local and global health promotion efforts.

15.
Front Public Health ; 11: 1253844, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098818

RESUMO

Introduction: The Chinese state has recently implemented the COVID-19 Vaccine Communication Campaign (CVCC) to counter vaccine hesitancy. Nonetheless, the extant literature that examines COVID-19 vaccine acceptance has less represented COVID-19 vaccine communication efforts. Methods: To address this lacuna, we qualitatively explored how CVCCs were organized in Chinese communities by investigating 54 Chinese stakeholders. Results: This study indicates that the CVCC was sustained by top-down political pressure. CVCCs' components involve ideological education among politically affiliated health workers, expanding health worker networks, training health workers, implementing media promotion, communicating with residents using persuasive and explanatory techniques, encouraging multistakeholder partnerships, and using public opinion-steered and coercive approaches. While CVCCs significantly enhanced COVID-19 vaccine acceptance, lacking open communication, stigmatizing vaccine refusers, insufficient stakeholder collaboration, and low trust in the COVID-19 vaccination program (CVP) eroded the validity of CVCCs. Discussion: To promote the continuity of CVCCs in China, CVCC performers are expected to conduct open and inclusive communication with residents. Furthermore, CVP planers should create robust partnerships among health workers by ensuring their agreements on strategies for implementing CVCCs and optimize COVID-19 immunization service provision to depoliticize CVPs. Our study will not only deepen global audiences' understanding of CVCCs in authoritarian China but also offer potential neighborhood-level solutions for implementing local and global public health communication efforts.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Comunicação , Pesquisa Qualitativa , China
16.
J Exp Med ; 220(3)2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36520461

RESUMO

Fatty acid uptake is essential for cell physiological function, but detailed mechanisms remain unclear. Here, we generated an acetyl-CoA carboxylases (ACC1/2) double-knockout cell line, which lacked fatty acid biosynthesis and survived on serum fatty acids and was used to screen for fatty acid uptake inhibitors. We identified a Food and Drug Administration-approved tricyclic antidepressant, nortriptyline, that potently blocked fatty acid uptake both in vitro and in vivo. We also characterized underlying mechanisms whereby nortriptyline provoked lysosomes to release protons and induce cell acidification to suppress macropinocytosis, which accounted for fatty acid endocytosis. Furthermore, nortriptyline alone or in combination with ND-646, a selective ACC1/2 inhibitor, significantly repressed tumor growth, lipogenesis, and hepatic steatosis in mice. Therefore, we show that cells actively take up fatty acids through macropinocytosis, and we provide a potential strategy suppressing tumor growth, lipogenesis, and hepatic steatosis through controlling the cellular level of fatty acids.


Assuntos
Fígado Gorduroso , Doenças Metabólicas , Neoplasias , Camundongos , Animais , Ácidos Graxos/metabolismo , Antidepressivos Tricíclicos/farmacologia , Antidepressivos Tricíclicos/uso terapêutico , Antidepressivos Tricíclicos/metabolismo , Nortriptilina/metabolismo , Nortriptilina/uso terapêutico , Reposicionamento de Medicamentos , Fígado Gorduroso/patologia , Doenças Metabólicas/metabolismo , Neoplasias/patologia , Fígado/metabolismo
17.
Nat Cell Biol ; 25(6): 836-847, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37291265

RESUMO

De novo pyrimidine biosynthesis is achieved by cytosolic carbamoyl-phosphate synthetase II, aspartate transcarbamylase and dihydroorotase (CAD) and uridine 5'-monophosphate synthase (UMPS), and mitochondrial dihydroorotate dehydrogenase (DHODH). However, how these enzymes are orchestrated remains enigmatical. Here we show that cytosolic glutamate oxaloacetate transaminase 1 clusters with CAD and UMPS, and this complex then connects with DHODH, which is mediated by the mitochondrial outer membrane protein voltage-dependent anion-selective channel protein 3. Therefore, these proteins form a multi-enzyme complex, named 'pyrimidinosome', involving AMP-activated protein kinase (AMPK) as a regulator. Activated AMPK dissociates from the complex to enhance pyrimidinosome assembly but inactivated UMPS, which promotes DHODH-mediated ferroptosis defence. Meanwhile, cancer cells with lower expression of AMPK are more reliant on pyrimidinosome-mediated UMP biosynthesis and more vulnerable to its inhibition. Our findings reveal the role of pyrimidinosome in regulating pyrimidine flux and ferroptosis, and suggest a pharmaceutical strategy of targeting pyrimidinosome in cancer treatment.


Assuntos
Ferroptose , Neoplasias , Di-Hidro-Orotato Desidrogenase , Proteínas Quinases Ativadas por AMP , Pirimidinas/farmacologia , Proliferação de Células
18.
Sci Adv ; 9(23): eade1155, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37294756

RESUMO

The EGFR-RAS-ERK pathway plays a key role in cancer development and progression. However, the integral assembly of EGFR-RAS-ERK signaling complexes from the upstream component EGFR to the downstream component ERK is largely unknown. Here, we show that hematopoietic PBX-interacting protein (HPIP) interacts with all classical components of the EGFR-RAS-ERK pathway and forms at least two complexes with overlapping components. Experiments of HPIP knockout or knockdown and chemical inhibition of HPIP expression showed that HPIP is required for EGFR-RAS-ERK signaling complex formation, EGFR-RAS-ERK signaling activation, and EGFR-RAS-ERK signaling-mediated promotion of aerobic glycolysis as well as cancer cell growth in vitro and in vivo. HPIP expression is correlated with EGFR-RAS-ERK signaling activation and predicts worse clinical outcomes in patients with lung cancer. These results provide insights into EGFR-RAS-ERK signaling complex formation and EGFR-RAS-ERK signaling regulation and suggest that HPIP may be a promising therapeutic target for cancer with dysregulated EGFR-RAS-ERK signaling.


Assuntos
Sistema de Sinalização das MAP Quinases , Fatores de Transcrição , Humanos , Fatores de Transcrição/metabolismo , Transformação Celular Neoplásica/genética , Receptores ErbB/genética
19.
Plant Physiol ; 156(1): 319-29, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21430185

RESUMO

We hypothesized that soybean cyst nematode (SCN; Heterodera glycines) co-opts part or all of one or more innate developmental process in soybean (Glycine max) to establish its feeding structure, syncytium, in soybean roots. The syncytium is formed within the vascular bundle by partial degradation of cell walls and membranes between adjacent parenchyma cells. A mature syncytium incorporates as many as 200 cells into one large multinucleated cell. Gene expression patterns for several cell wall-modifying proteins were compared in multiple tissues undergoing major shifts in cell wall integrity. These included SCN-colonized roots, root tips where vascular differentiation occurs, flooded roots (aerenchyma), adventitious rooting in hypocotyls, and leaf abscission zones. A search in the 5' upstream promoters of these genes identified a motif (SCNbox1: WGCATGTG) common to several genes that were up-regulated in several different tissues. The polygalacturonase 11 promoters (GmPG11a/b) include the SCNbox1 motif. The expression pattern for GmPG11a was examined further in transgenic soybean containing a PG11a promoter fused to a ß-glucuronidase (GUS) reporter gene. GUS expression was highest in cells undergoing radial expansion in the stele and/or cell wall dissolution. GUS staining was not observed in cortical cells where a lateral root tip or a growing nematode emerged through the root cortex.


Assuntos
Regulação da Expressão Gênica de Plantas , Glycine max/enzimologia , Interações Hospedeiro-Parasita , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Tylenchoidea/fisiologia , Animais , Parede Celular/enzimologia , Feminino , Perfilação da Expressão Gênica , Genes Reporter , Biblioteca Genômica , Motivos de Nucleotídeos , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , RNA de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Glycine max/genética , Glycine max/parasitologia
20.
Cells ; 11(24)2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36552752

RESUMO

The roles of lamin A/C in adipocyte differentiation and skeletal muscle lipid metabolism are associated with familial partial lipodystrophy of Dunnigan (FPLD). We confirmed that LMNA knockdown (KD) in mouse adipose-derived mesenchymal stem cells (AD-MSCs) prevented adipocyte maturation. Importantly, in in vitro experiments, we discovered a significant increase in phosphorylated lamin A/C levels at serine 22 or 392 sites (pLamin A/C-S22/392) accompanying increased lipid synthesis in a liver cell line (7701 cells) and two hepatocellular carcinoma (HCC) cell lines (HepG2 and MHCC97-H cells). Moreover, HCC cells did not survive after LMNA knockout (KO) or even KD. Evidently, the functions of lamin A/C differ between the liver and adipose tissue. To date, the mechanism of hepatocyte lipid metabolism mediated by nuclear lamin A/C remains unclear. Our in-depth study aimed to identify the molecular connection between lamin A/C and pLamin A/C, hepatic lipid metabolism and liver cancer. Gain- and loss-of-function experiments were performed to investigate functional changes and the related molecular pathways in 7701 cells. Adenosine 5' monophosphate-activated protein kinase α (AMPKα) was activated when abnormalities in functional lamin A/C were observed following lamin A/C depletion or farnesyltransferase inhibitor (FTI) treatment. Active AMPKα directly phosphorylated acetyl-CoA-carboxylase 1 (ACC1) and subsequently inhibited lipid synthesis but induced glycolysis in both HCC cells and normal cells. According to the mass spectrometry analysis, lamin A/C potentially regulated AMPKα activation through its chaperone proteins, ATPase or ADP/ATP transporter 2. Lonafarnib (an FTI) combined with low-glucose conditions significantly decreased the proliferation of the two HCC cell lines more efficiently than lonafarnib alone by inhibiting glycolysis or the maturation of prelamin A.


Assuntos
Proteínas Quinases Ativadas por AMP , Carcinoma Hepatocelular , Lamina Tipo A , Neoplasias Hepáticas , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Homeostase , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Lipídeos/fisiologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo
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