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1.
BMC Res Notes ; 14(1): 335, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454571

RESUMO

OBJECTIVE: We previously identified propionic acid as a microbially-produced volatile organic compound with fungicidal activity against several pathogenic fungi. The purpose of this work is to better understand how propionic acid affects fungi by examining some of the effects of this compound on the yeast cell. RESULTS: We show that propionic acid causes a dramatic increase in the uptake of lucifer yellow in yeast cells, which is consistent with enhanced endocytosis. Additionally, using a propidium iodide assay, we show that propionic acid treatment causes a significant increase in the proportion of yeast cells in G1 and a significant decrease in the proportion of cells in G2, suggesting that propionic acid causes a cell cycle arrest in yeast. Finally, we show that the reduction of MTT is attenuated in yeast cells treated with propionic acid, indicating that propionic acid disrupts cellular respiration. Understanding the effects of propionic acid on the yeast cell may aid in assessing the broader utility of this compound.


Assuntos
Respiração Celular , Saccharomyces cerevisiae , Ciclo Celular , Endocitose , Propionatos
2.
Nat Commun ; 12(1): 4791, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373452

RESUMO

Classical dendritic cells (cDC) are professional antigen-presenting cells (APC) that regulate immunity and tolerance. Neutrophil-derived cells with properties of DCs (nAPC) are observed in human diseases and after culture of neutrophils with cytokines. Here we show that FcγR-mediated endocytosis of antibody-antigen complexes or an anti-FcγRIIIB-antigen conjugate converts neutrophils into nAPCs that, in contrast to those generated with cytokines alone, activate T cells to levels observed with cDCs and elicit CD8+ T cell-dependent anti-tumor immunity in mice. Single cell transcript analyses and validation studies implicate the transcription factor PU.1 in neutrophil to nAPC conversion. In humans, blood nAPC frequency in lupus patients correlates with disease. Moreover, anti-FcγRIIIB-antigen conjugate treatment induces nAPCs that can activate autologous T cells when using neutrophils from individuals with myeloid neoplasms that harbor neoantigens or those vaccinated against bacterial toxins. Thus, anti-FcγRIIIB-antigen conjugate-induced conversion of neutrophils to immunogenic nAPCs may represent a possible immunotherapy for cancer and infectious diseases.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias/imunologia , Neutrófilos/imunologia , Receptores de IgG/genética , Receptores de IgG/imunologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Apresentação do Antígeno/imunologia , Complexo Antígeno-Anticorpo , Medula Óssea , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Movimento Celular , Proliferação de Células , Citocinas/imunologia , Células Dendríticas/imunologia , Endocitose , Humanos , Imunidade Inata , Imunoterapia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Espécies Reativas de Oxigênio , Transcriptoma
3.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445520

RESUMO

Endocytic trafficking is an under-appreciated pathway in cardiac development. Several genes related to endocytic trafficking have been uncovered in a mutagenic ENU screen, in which mutations led to congenital heart defects (CHDs). In this article, we review the relationship between these genes (including LRP1 and LRP2) and cardiac neural crest cells (CNCCs) during cardiac development. Mice with an ENU-induced Lrp1 mutation exhibit a spectrum of CHDs. Conditional deletion using a floxed Lrp1 allele with different Cre drivers showed that targeting neural crest cells with Wnt1-Cre expression replicated the full cardiac phenotypes of the ENU-induced Lrp1 mutation. In addition, LRP1 function in CNCCs is required for normal OFT lengthening and survival/expansion of the cushion mesenchyme, with other cell lineages along the NCC migratory path playing an additional role. Mice with an ENU-induced and targeted Lrp2 mutation demonstrated the cardiac phenotype of common arterial trunk (CAT). Although there is no impact on CNCCs in Lrp2 mutants, the loss of LRP2 results in the depletion of sonic hedgehog (SHH)-dependent cells in the second heart field. SHH is known to be crucial for CNCC survival and proliferation, which suggests LRP2 has a non-autonomous role in CNCCs. In this article, other endocytic trafficking proteins that are associated with CHDs that may play roles in the NCC pathway during development, such as AP1B1, AP2B1, FUZ, MYH10, and HECTD1, are reviewed.


Assuntos
Etilnitrosoureia/efeitos adversos , Cardiopatias Congênitas/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Animais , Linhagem da Célula , Modelos Animais de Doenças , Endocitose , Cardiopatias Congênitas/induzido quimicamente , Camundongos , Mutação , Crista Neural/metabolismo , Transdução de Sinais
4.
Nat Commun ; 12(1): 4697, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349123

RESUMO

Polarized epithelial cells can organize into complex structures with a characteristic central lumen. Lumen formation requires that cells coordinately orient their polarity axis so that the basolateral domain is on the outside and apical domain inside epithelial structures. Here we show that the transmembrane aminopeptidase, CD13, is a key determinant of epithelial polarity orientation. CD13 localizes to the apical membrane and associates with an apical complex with Par6. CD13-deficient cells display inverted polarity in which apical proteins are retained on the outer cell periphery and fail to accumulate at an intercellular apical initiation site. Here we show that CD13 is required to couple apical protein cargo to Rab11-endosomes and for capture of endosomes at the apical initiation site. This role in polarity utilizes the short intracellular domain but is independent of CD13 peptidase activity.


Assuntos
Antígenos CD13/metabolismo , Polaridade Celular , Células Epiteliais/citologia , Epitélio/crescimento & desenvolvimento , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antígenos CD13/química , Antígenos CD13/genética , Células CACO-2 , Membrana Celular/metabolismo , Endocitose , Endossomos/metabolismo , Células Epiteliais/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Domínios Proteicos , Proteínas rab de Ligação ao GTP/metabolismo
6.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361779

RESUMO

Delivering nucleic acids into the endothelium has great potential in treating vascular diseases. However, endothelial cells, which line the vasculature, are considered as sensitive in nature and hard to transfect. Low transfection efficacies in endothelial cells limit their potential therapeutic applications. Towards improving the transfection efficiency, we made an effort to understand the internalization of lipoplexes into the cells, which is the first and most critical step in nucleic acid transfections. In this study, we demonstrated that the transient modulation of caveolae/lipid rafts mediated endocytosis with the cholesterol-sequestrating agents, nystatin, filipin III, and siRNA against Cav-1, which significantly increased the transfection properties of cationic lipid-(2-hydroxy-N-methyl-N,N-bis(2-tetradecanamidoethyl)ethanaminium chloride), namely, amide liposomes in combination with 1,2-Dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) (AD Liposomes) in liver sinusoidal endothelial cells (SK-Hep1). In particular, nystatin was found to be highly effective with 2-3-fold enhanced transfection efficacy when compared with amide liposomes in combination with Cholesterol (AC), by switching lipoplex internalization predominantly through clathrin-mediated endocytosis and macropinocytosis.


Assuntos
Cavéolas/efeitos dos fármacos , Colesterol/química , Células Endoteliais/efeitos dos fármacos , Lipossomos/química , Microdomínios da Membrana/efeitos dos fármacos , Transfecção/métodos , Animais , Cavéolas/química , Cavéolas/metabolismo , Caveolina 1/antagonistas & inibidores , Caveolina 1/genética , Caveolina 1/metabolismo , Linhagem Celular Transformada , Colesterol/metabolismo , Clatrina/metabolismo , DNA/química , DNA/metabolismo , Endocitose/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Filipina/química , Filipina/farmacologia , Expressão Gênica , Lipossomos/metabolismo , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo , Nistatina/química , Nistatina/farmacologia , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/farmacologia , Pinocitose/efeitos dos fármacos , Plasmídeos/química , Plasmídeos/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos
7.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443689

RESUMO

Effective intracerebral delivery is key for glioma treatment. However, the drug delivery system within the brain is largely limited by its own adverse physical and chemical properties, low targeting efficiency, the blood-brain barrier and the blood-brain tumor barrier. Herein, we developed a simple, safe and efficient biomimetic nanosuspension. The C6 cell membrane (CCM) was utilized to camouflaged the 10-hydroxycamptothecin nanosuspension (HCPT-NS) in order to obtain HCPT-NS/CCM. Through the use of immune escape and homotypic binding of the cancer cell membrane, HCPT-NS/CCM was able to penetrate the blood-brain barrier and target tumors. The HCPT-NS is only comprised of drugs, as well as a small amount of stabilizers that are characterized by a simple preparation method and high drug loading. Similarly, the HCPT-NS/CCM is able to achieve targeted treatment of glioma without any ligand modification, which leads it to be stable and efficient. Cellular uptake and in vivo imaging experiments demonstrated that HCPT-NS/CCM is able to effectively cross the blood-brain barrier and was concentrated at the glioma site due to the natural homing pathway. Our results reveal that the glioma cancer cell membrane is able to promote drug transport into the brain and enter the tumor via a homologous targeting mechanism.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Membrana Celular/patologia , Glioma/tratamento farmacológico , Glioma/patologia , Nanopartículas/química , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos Endogâmicos ICR , Nanopartículas/ultraestrutura , Ratos , Suspensões , Distribuição Tecidual/efeitos dos fármacos , Resultado do Tratamento
8.
ACS Appl Mater Interfaces ; 13(33): 39076-39087, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378375

RESUMO

Fluorophores with multifunctional properties known as rare-earth-doped nanoparticles (RENPs) are promising candidates for bioimaging, therapy, and drug delivery. When applied in vivo, these nanoparticles (NPs) have to retain long blood-circulation time, bypass elimination by phagocytic cells, and successfully arrive at the target area. Usually, NPs in a biological medium are exposed to proteins, which form the so-called "protein corona" (PC) around the NPs and influence their targeted delivery and accumulation in cells and tissues. Different surface coatings change the PC size and composition, subsequently deciding the fate of the NPs. Thus, detailed studies on the PC are of utmost importance to determine the most suitable NP surface modification for biomedical use. When it comes to RENPs, these studies are particularly scarce. Here, we investigate the PC composition and its impact on the cellular uptake of citrate-, SiO2-, and phospholipid micelle-coated RENPs (LiYF4:Yb3+,Tm3+). We observed that the PC of citrate- and phospholipid-coated RENPs is relatively stable and similar in the adsorbed protein composition, while the PC of SiO2-coated RENPs is larger and highly dynamic. Moreover, biocompatibility, accumulation, and cytotoxicity of various RENPs in cancer cells have been evaluated. On the basis of the cellular imaging, supported by the inhibition studies, it was revealed that RENPs are internalized by endocytosis and that specific endocytic routes are PC composition dependent. Overall, these results are essential to fill the gaps in the fundamental understanding of the nano-biointeractions of RENPs, pertinent for their envisioned application in biomedicine.


Assuntos
Materiais Revestidos Biocompatíveis/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Metais Terras Raras/química , Coroa de Proteína/metabolismo , Dióxido de Silício/química , Adsorção , Neoplasias da Mama , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Ácido Cítrico/química , Materiais Revestidos Biocompatíveis/metabolismo , Endocitose , Corantes Fluorescentes/metabolismo , Humanos , Tamanho da Partícula , Fosfolipídeos/química , Propriedades de Superfície
9.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360836

RESUMO

Lysyl oxidase-like 3 (LOXL3), belonging to the lysyl oxidase family, is responsible for the crosslinking in collagen or elastin. The cellular localization of LOXL3 is in the extracellular space by reason of its canonical function. In tumors, the presence of LOXL3 has been associated with genomic stability, cell proliferation, and metastasis. In silico analysis has shown that glioblastoma was among tumors with the highest LOXL3 expression levels. LOXL3 silencing of U87MG cells by siRNA led to the spreading of the tumor cell surface, and the transcriptome analysis of these cells revealed an upregulation of genes coding for extracellular matrix, cell adhesion, and cytoskeleton components, convergent to an increase in cell adhesion and a decrease in cell invasion observed in functional assays. Significant correlations of LOXL3 expression with genes coding for tubulins were observed in the mesenchymal subtype in the TCGA RNA-seq dataset of glioblastoma (GBM). Conversely, genes involved in endocytosis and lysosome formation, along with MAPK-binding proteins related to focal adhesion turnover, were downregulated, which may corroborate the observed decrease in cell viability and increase in the rate of cell death. Invasiveness is a major determinant of the recurrence and poor outcome of GBM patients, and downregulation of LOXL3 may contribute to halting the tumor cell invasion.


Assuntos
Aminoácido Oxirredutases/metabolismo , Adesão Celular , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , Simulação por Computador , Citoesqueleto/metabolismo , Endocitose , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Humanos , Lisossomos/fisiologia , Invasividade Neoplásica
10.
Nat Commun ; 12(1): 4688, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344896

RESUMO

Internalization and intracellular trafficking of G protein-coupled receptors (GPCRs) play pivotal roles in cell responsiveness. Dysregulation in receptor trafficking can lead to aberrant signaling and cell behavior. Here, using an endosomal BRET-based assay in a high-throughput screen with the prototypical GPCR angiotensin II type 1 receptor (AT1R), we sought to identify receptor trafficking inhibitors from a library of ~115,000 small molecules. We identified a novel dual Ras and ARF6 inhibitor, which we named Rasarfin, that blocks agonist-mediated internalization of AT1R and other GPCRs. Rasarfin also potently inhibits agonist-induced ERK1/2 signaling by GPCRs, and MAPK and Akt signaling by EGFR, as well as prevents cancer cell proliferation. In silico modeling and in vitro studies reveal a unique binding modality of Rasarfin within the SOS-binding domain of Ras. Our findings unveil a class of dual small G protein inhibitors for receptor trafficking and signaling, useful for the inhibition of oncogenic cellular responses.


Assuntos
Fatores de Ribosilação do ADP/antagonistas & inibidores , Endocitose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Proteínas ras/antagonistas & inibidores , Fatores de Ribosilação do ADP/metabolismo , Sítios de Ligação , Técnicas de Transferência de Energia por Ressonância de Bioluminescência , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Células HEK293 , Humanos , Simulação de Dinâmica Molecular , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas ras/química , Proteínas ras/metabolismo
11.
J Gen Virol ; 102(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34356005

RESUMO

The family Arteriviridae comprises enveloped RNA viruses with a linear, positive-sense genome of approximately 12.7 to 15.7 kb. The spherical, pleomorphic virions have a median diameter of 50-74 nm and include eight to eleven viral proteins. Arteriviruses infect non-human mammals in a vector-independent manner. Infections are often persistent and can either be asymptomatic or produce overt disease. Some arteriviruses are important veterinary pathogens while others infect particular species of wild rodents or African non-human primates. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Arteriviridae, which is available at ictv.global/report/arteriviridae.


Assuntos
Arteriviridae/classificação , Arteriviridae/genética , Filogenia , Animais , Arteriviridae/ultraestrutura , Arterivirus/classificação , Arterivirus/genética , Endocitose , Genoma Viral , Primatas , Infecções por Vírus de RNA , Proteínas Virais/genética , Vírion/classificação , Vírion/genética , Vírion/ultraestrutura , Ligação Viral , Replicação Viral
12.
Nat Commun ; 12(1): 4863, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381050

RESUMO

Spreading of aggregate pathology across brain regions acts as a driver of disease progression in Tau-related neurodegeneration, including Alzheimer's disease (AD) and frontotemporal dementia. Aggregate seeds released from affected cells are internalized by naïve cells and induce the prion-like templating of soluble Tau into neurotoxic aggregates. Here we show in a cellular model system and in neurons that Clusterin, an abundant extracellular chaperone, strongly enhances Tau aggregate seeding. Upon interaction with Tau aggregates, Clusterin stabilizes highly potent, soluble seed species. Tau/Clusterin complexes enter recipient cells via endocytosis and compromise the endolysosomal compartment, allowing transfer to the cytosol where they propagate aggregation of endogenous Tau. Thus, upregulation of Clusterin, as observed in AD patients, may enhance Tau seeding and possibly accelerate the spreading of Tau pathology.


Assuntos
Clusterina/metabolismo , Agregação Patológica de Proteínas/metabolismo , Proteínas tau/metabolismo , Animais , Clusterina/genética , Progressão da Doença , Endocitose , Humanos , Camundongos , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurônios/metabolismo , Neurônios/patologia , Agregação Patológica de Proteínas/patologia , Ligação Proteica , alfa-Sinucleína/metabolismo , Proteínas tau/genética
13.
Development ; 148(14)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34269385

RESUMO

Fertilization triggers significant cellular remodeling through the oocyte-to-embryo transition. In this transition, the ubiquitin-proteasome system and autophagy are essential for the degradation of maternal components; however, the significance of degradation of cell surface components remains unknown. In this study, we show that multiple maternal plasma membrane proteins, such as the glycine transporter GlyT1a, are selectively internalized from the plasma membrane to endosomes in mouse embryos by the late two-cell stage and then transported to lysosomes for degradation at the later stages. During this process, large amounts of ubiquitylated proteins accumulated on endosomes. Furthermore, the degradation of GlyT1a with mutations in potential ubiquitylation sites was delayed, suggesting that ubiquitylation may be involved in GlyT1a degradation. The clathrin inhibitor blocked GlyT1a internalization. Strikingly, the protein kinase C (PKC) activator triggered the heterochronic internalization of GlyT1a; the PKC inhibitor markedly blocked GlyT1a endocytosis. Lastly, clathrin inhibition completely blocked embryogenesis at the two-cell stage and inhibited cell division after the four-cell stage. These findings demonstrate that PKC-dependent clathrin-mediated endocytosis is essential for the selective degradation of maternal membrane proteins during oocyte-to-embryo transition and early embryogenesis.


Assuntos
Clatrina/metabolismo , Desenvolvimento Embrionário/fisiologia , Endocitose/fisiologia , Proteínas de Membrana/metabolismo , Animais , Membrana Celular/metabolismo , Embrião de Mamíferos , Endossomos/metabolismo , Feminino , Fertilização , Proteínas da Membrana Plasmática de Transporte de Glicina , Masculino , Camundongos , Oócitos , Proteína Quinase C , Ubiquitina/metabolismo , Ubiquitinação
14.
J Photochem Photobiol B ; 221: 112257, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34271410

RESUMO

Organic semiconductor small molecules IHIC and ITIC have been developed as solar cell materials, and because of their strong near-infrared absorption capabilities, they are promising for cancer phototherapy. This article reports the application of semiconductor small molecule IHIC/ITIC liposomes in photothermal therapy and photoacoustic imaging of tumors firstly. Experiments show that the liposome-loaded IHIC/ITIC material has good biocompatibility and can be effectively enriched in tumor sites. After being irradiated with laser, it can emit strong photoacoustic signals, and has achieved good results in the photothermal treatment of breast cancer mice. We believe that organic semiconductor small molecule IHIC/ITIC will become a promising photothermal agent with wonderful development possibilities.


Assuntos
Materiais Biocompatíveis/química , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Semicondutores , Animais , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Endocitose/efeitos da radiação , Células HeLa , Humanos , Lasers , Lipossomos/química , Camundongos , Camundongos Nus , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Tamanho da Partícula , Técnicas Fotoacústicas , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Terapia Fototérmica , Transplante Heterólogo
15.
Biomed Pharmacother ; 139: 111667, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243608

RESUMO

Interactions between vascular smooth muscle cells (VSMCs), endothelial cells (ECs), pericytes (PCs) and macrophages (MФ), the major components of blood vessels, play a crucial role in maintaining vascular structural and functional homeostasis. Low-density lipoprotein (LDL) receptor-related protein-1 (LRP1), a transmembrane receptor protein belonging to the LDL receptor family, plays multifunctional roles in maintaining endocytosis, homeostasis, and signal transduction. Accumulating evidence suggests that LRP1 modulates vascular homeostasis mainly by regulating vasoactive substances and specific intracellular signaling pathways, including the plasminogen activator inhibitor 1 (PAI-1) signaling pathway, platelet-derived growth factor (PDGF) signaling pathway, transforming growth factor-ß (TGF-ß) signaling pathway and vascular endothelial growth factor (VEGF) signaling pathway. The aim of the present review is to focus on recent advances in the discovery and mechanism of vascular homeostasis regulated by LRP1-dependent signaling pathways. These recent discoveries expand our understanding of the mechanisms controlling LRP1 as a target for studies on vascular complications.


Assuntos
Homeostase/fisiologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Músculo Liso Vascular/metabolismo , Transdução de Sinais/fisiologia , Animais , Endocitose/fisiologia , Células Endoteliais/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Miócitos de Músculo Liso/metabolismo
16.
J Cell Sci ; 134(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34313314

RESUMO

Ligand-receptor complexes formed at the plasma membrane are internalised via various endocytic pathways that influence the ultimate signalling output by regulating the selection of interaction partners by the complex along the trafficking route. We report that, in differentiated cells, activin A-receptor complexes are internalised via clathrin-mediated endocytosis (CME) and macropinocytosis (MP), whereas in human embryonic stem cells (hESCs) internalisation occurs via CME. We further show that hESCs are devoid of MP, which becomes functional upon differentiation towards endothelial cells through mesoderm mediators. Our results reveal, for the first time, that MP is an internalisation route for activin A in differentiated cells, and that MP is not active in hESCs and is induced as cells differentiate.


Assuntos
Ativinas , Células Endoteliais , Diferenciação Celular , Células-Tronco Embrionárias , Endocitose , Humanos
17.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207305

RESUMO

The COVID-19 pandemic caused by SARS-CoV-2 coronavirus deeply affected the world community. It gave a strong impetus to the development of not only approaches to diagnostics and therapy, but also fundamental research of the molecular biology of this virus. Fluorescence microscopy is a powerful technology enabling detailed investigation of virus-cell interactions in fixed and live samples with high specificity. While spatial resolution of conventional fluorescence microscopy is not sufficient to resolve all virus-related structures, super-resolution fluorescence microscopy can solve this problem. In this paper, we review the use of fluorescence microscopy to study SARS-CoV-2 and related viruses. The prospects for the application of the recently developed advanced methods of fluorescence labeling and microscopy-which in our opinion can provide important information about the molecular biology of SARS-CoV-2-are discussed.


Assuntos
Microscopia de Fluorescência , SARS-CoV-2/fisiologia , COVID-19/patologia , COVID-19/virologia , Endocitose , Corantes Fluorescentes/química , Genes Reporter , Humanos , RNA Viral/química , RNA Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus
18.
Nat Commun ; 12(1): 4327, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267202

RESUMO

Trivalent rare earth elements (REEs) are widely used in agriculture. Aerially applied REEs enter leaf epidermal cells by endocytosis and act systemically to improve the growth of the whole plant. The mechanistic basis of their systemic activity is unclear. Here, we show that treatment of Arabidopsis leaves with trivalent lanthanum [La(III)], a representative of REEs, triggers systemic endocytosis from leaves to roots. La(III)-induced systemic endocytosis requires AtrbohD-mediated reactive oxygen species production and jasmonic acid. Systemic endocytosis impacts the accumulation of mineral elements and the development of roots consistent with the growth promoting effects induced by aerially applied REEs. These findings provide insights into the mechanistic basis of REE activity in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Lantânio/farmacologia , NADPH Oxidases/metabolismo , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Ciclopentanos/metabolismo , Endocitose/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/genética , Minerais/metabolismo , NADPH Oxidases/genética , Oxilipinas/metabolismo , Células Vegetais/efeitos dos fármacos , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais
19.
Int J Nanomedicine ; 16: 4677-4691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262275

RESUMO

Background: The clinical use of therapeutic peptides has been limited because of their inefficient delivery approaches and, therefore, inadequate delivery to target sites. Buccal administration of therapeutic peptides offers patients a potential alternative to the current invasive routes of administration. Purpose: The aim of the study was to fabricate hydrophobic ion-pairing (HIP)-nanocomplexes (C1 and C2) utilizing anionic bile salts and cationic peptides, and to assess their permeability across TR146 buccal cell layers and porcine buccal tissue. Methods: C1 and C2-nanocomplexes were fabricated using the HIP approach. In addition, their physiochemical and morphological attributes, in vitro and ex vivo permeability properties, and qualitative and quantitative cellular uptake were evaluated and compared. The localization of C1 and C2-nanocomplexes in porcine buccal tissue was determined using confocal laser scanning microscopy. Results: The C1-nanocomplex was the superior nanocarrier and significantly enhanced the transport of insulin across TR146 cell layers and porcine buccal tissue, exhibiting a 3.00- and 51.76-fold increase in permeability coefficient, respectively, when compared with insulin solution (p < 0.01). C1-nanocomplex was more efficient than C2-nanocomplex at facilitating insulin permeability, with a 2.18- and 27.64-fold increase across TR146 cell layers and porcine buccal tissue, respectively. The C1-nanocomplex demonstrated immense uptake and localization of insulin in TR146 cells and porcine buccal tissue, as evidenced by a highly intense fluorescence in TR146 cells, and a great shift of fluorescence intensity towards the inner region of buccal tissue over time. The increase in fluorescence intensity was observed in the order of C1 > C2 > insulin solution. Conclusion: In this study, we highlighted the efficacy of potential nanocarriers in addressing the daunting issues associated with the invasive administration of insulin and indicated a promising strategy for the buccal administration and delivery of this life-saving peptide hormone.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Insulina/administração & dosagem , Insulina/farmacologia , Mucosa Bucal/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Endocitose/efeitos dos fármacos , Humanos , Íons , Nanopartículas/química , Nanopartículas/ultraestrutura , Suínos
20.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209489

RESUMO

The endocytosis of ligand-bound receptors and their eventual recycling to the plasma membrane (PM) are processes that have an influence on signalling activity and therefore on many cell functions, including migration and proliferation. Like other tyrosine kinase receptors (TKR), the insulin receptor (INSR) has been shown to be endocytosed by clathrin-dependent and -independent mechanisms. Once at the early endosome (EE), the sorting of the receptor, either to the late endosome (LE) for degradation or back to the PM through slow or fast recycling pathways, will determine the intensity and duration of insulin effects. Both the endocytic and the endosomic pathways are regulated by many proteins, the Arf and Rab families of small GTPases being some of the most relevant. Here, we argue for a specific role for the slow recycling route, whilst we review the main molecular mechanisms involved in INSR endocytosis, sorting and recycling, as well as their possible role in cell functions.


Assuntos
Endossomos/metabolismo , Receptor de Insulina/metabolismo , Animais , Proteínas de Transporte , Membrana Celular/metabolismo , Movimento Celular , Proliferação de Células , Clatrina/metabolismo , Endocitose , Humanos , Lisossomos , Ligação Proteica , Transporte Proteico , Receptor de Insulina/agonistas , Vesículas Transportadoras/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
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