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1.
Front Cell Infect Microbiol ; 14: 1467440, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39397861

RESUMO

In humans and Drosophila melanogaster, the functional convergence of the endosomal sorting complex required for transport (ESCRT) machinery that is in charge of selecting ubiquitinated proteins for sorting into multivesicular bodies, and the retromer, that is the complex responsible for protein recycling to the plasma membrane and Golgi apparatus. ESCRT and retromer complexes are codependent for protein sorting recycling, degradation, and secretion. In this article, we studied the EhVps35 C isoform (referred to as EhVps35), that is the central member of the Entamoeba histolytica retromer, and its relation with the ESCRT machinery during sorting and protein recycling events and their involvement virulence. Our findings revealed that EhVps35 interacts with at least 300 proteins that participate in multiple cellular processes. Laser confocal and transmission electronic microscopy images, as well as secretion assays, revealed that EhVps35 is secreted in vesicles together with EhVps23 and EhADH (both ESCRT machinery proteins). In addition, immunoprecipitation, immunofluorescence, and molecular docking assays revealed the relationship among EhVps35 and other ESCRT machinery proteins. Red blood cell stimulus increased EhVps35 secretion, and the knockdown of the Ehvps35 gene in trophozoites reduced their capacity to migrate and invade tissues. This also impacts the cellular localization of ubiquitin, EhVps23 (ESCRT-I), and EhVps32 (ESCRT-III) proteins, strongly suggesting their functional relationship. Our results, taken together, give evidence that EhVps35 is a key factor in E. histolytica virulence mechanisms and that it, together with the ESCRT machinery components and other regulatory proteins, is involved in vesicle trafficking, secretion, migration, and cell proliferation.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Entamoeba histolytica , Transporte Proteico , Proteínas de Protozoários , Entamoeba histolytica/metabolismo , Entamoeba histolytica/patogenicidade , Entamoeba histolytica/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Animais , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Humanos , Virulência , Simulação de Acoplamento Molecular , Eritrócitos/parasitologia , Eritrócitos/metabolismo , Fatores de Virulência/metabolismo , Entamebíase/parasitologia
2.
J Biomed Sci ; 31(1): 97, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369194

RESUMO

Recent advances in studies exploring the roles of extracellular vesicles (EVs) in viral transmission and replication have illuminated hepatotropic viruses, such as hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV). While previous investigations have uncovered these viruses' ability to exploit cellular EV pathways for replication and transmission, most have focused on the impacts of exosomal pathways. With an improved understanding of EVs, four main subtypes, including exosomes, microvesicles, large oncosomes, and apoptotic bodies, have been categorized based on size and biogenic pathways. However, there remains a noticeable gap in comprehensive reviews summarizing recent findings and outlining future perspectives for EV studies related to hepatotropic viruses. This review aims to consolidate insights into EV pathways utilized by hepatotropic viruses, offering guidance for the future research direction in this field. By comprehending the diverse range of hepatotropic virus-associated EVs and their role in cellular communication during productive viral infections, this review may offer valuable insights for targeting therapeutics and devising strategies to combat virulent hepatotropic virus infections and the associated incidence of liver cancer.


Assuntos
Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/virologia , Humanos , Vírus de Hepatite/fisiologia , Vírus de Hepatite/genética
3.
Neuroscience ; 560: 347-356, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369944

RESUMO

Snf7-3 is a crucial component of the endosomal sorting complexes required for transport (ESCRT) pathway, playing a vital role in endolysosomal functions. To elucidate the role of Snf7-3 in vivo, we developed conventional-like and conditional Snf7-3 knockout (KO) mouse models using a "Knockout-first" strategy. Conventional-like Snf7-3 KO mice showed significantly reduced Snf7-3 mRNA expression, and older mice (25-40 weeks) exhibited impaired social recognition and increased miniature excitatory postsynaptic currents (mEPSCs). Similarly, conditional KO mice aged 8-24 weeks, with Snf7-3 specifically deleted in forebrain excitatory neurons, displayed impaired object location memory and elevated mEPSC frequency. Consistently, Snf7-3 knockdown in cultured mouse hippocampal neurons led to increased densities of pre- and postsynaptic puncta, supporting the observed increase in mEPSC frequency. In addition, enhanced dendritic complexity was observed in the medial prefrontal cortex of these mice, indicating early synaptic disturbances. Our findings underscore the critical role of Snf7-3 in maintaining normal cognitive functions and social behaviors. The observed synaptic and behavioral deficits in both conventional-like and conditional KO mice highlight the importance of Snf7-3 in specific neuronal populations, suggesting that early synaptic changes could precede more pronounced cognitive impairments.

4.
Cell Chem Biol ; 31(9): 1627-1635, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39303699

RESUMO

The dynamic process of membrane shaping and remodeling plays a vital role in cellular functions, with proteins and cellular membranes interacting intricately to adapt to various cellular needs and environmental cues. Ubiquitination-a posttranslational modification-was shown to be essential in regulating membrane structure and shape. It influences virtually all pathways relying on cellular membranes, such as endocytosis and autophagy by directing protein degradation, sorting, and oligomerization. Ubiquitin is mostly known as a protein modifier; however, it was reported that ubiquitin and ubiquitin-like proteins can associate directly with lipids, affecting membrane curvature and dynamics. In this review, we summarize some of the current knowledge on ubiquitin-mediated membrane remodeling in the context of endocytosis, autophagy, and ER-phagy.


Assuntos
Membrana Celular , Ubiquitina , Ubiquitinação , Ubiquitina/metabolismo , Humanos , Membrana Celular/metabolismo , Autofagia , Endocitose , Animais , Retículo Endoplasmático/metabolismo
5.
Biochem Biophys Res Commun ; 733: 150724, 2024 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-39332155

RESUMO

3,3'-Diindolylmethane is recognized for its anti-cancer activities in various pathways, though its mechanism remains to be fully elucidated. Previous studies have shown that 3,3'-Diindolylmethane disturbed the localization of Cut11, a nuclear pore complex subunit in Schizosaccharomyces pombe. This study further reveals that in Schizosaccharomyces pombe, 3,3'-Diindolylmethane also disrupts other components of nuclear envelope, causing GFP-NLS leakage, making it evident that 3,3'-Diindolylmethane disrupts the nuclear envelope. 3,3'-Diindolylmethane also disturbs the localization of GFP-ADEL and Ost4, which are endoplasmic reticulum lumen proteins and membrane proteins respectively, suggesting the function of 3,3'-Diindolylmethane on endoplasmic reticulum disturbance. The nuclear envelope repairment, normal nuclear envelope physical properties, and lipid metabolism homeostasis are crucial for cell survival in the presence of 3,3'-Diindolylmethane. These findings provide new insights into the understanding and development of 3,3'-Diindolylmethane as an anti-cancer agent.


Assuntos
Retículo Endoplasmático , Indóis , Membrana Nuclear , Schizosaccharomyces , Schizosaccharomyces/efeitos dos fármacos , Schizosaccharomyces/metabolismo , Indóis/farmacologia , Membrana Nuclear/metabolismo , Membrana Nuclear/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/genética
6.
Int J Mol Sci ; 25(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39337546

RESUMO

Newcastle disease virus (NDV) is a highly pathogenic avian infectious disease agent and also a promising oncolytic virus with broad application prospects. The Endosomal Sorting Complex Required for Transport (ESCRT) machinery has been increasingly recognized for its crucial role in the life cycles of enveloped viruses, influencing processes such as viral entry, replication, and budding. In this study, we employed an RNA interference screening approach to identify key ESCRT components that regulate NDV replication in tumor cells. qPCR, immunofluorescence, and Western blot assays demonstrated that knockdown of HRS, CHMP4A, CHMP4B, and CHMP4C significantly impaired NDV replication in HeLa cells, with HRS exhibiting the most pronounced inhibitory effect. Additionally, HRS knockout significantly inhibited viral budding and suppressed NDV-induced cell death in HeLa cells. Notably, NDV infection was shown to significantly upregulate HRS gene and protein expression in a time-dependent manner. In conclusion, this study systematically identifies critical ESCRT components involved in NDV replication within tumor cells, with a particular focus on the role of HRS in promoting NDV's replication by promoting viral budding, offering new insights for the development of NDV-based oncolytic therapies.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Vírus da Doença de Newcastle , Liberação de Vírus , Replicação Viral , Vírus da Doença de Newcastle/fisiologia , Vírus da Doença de Newcastle/genética , Humanos , Células HeLa , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Vírus Oncolíticos/fisiologia , Vírus Oncolíticos/genética , Animais
7.
Genetics ; 228(2)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39271159

RESUMO

The endosomal sorting complex required for transport (ESCRT)-III is involved in membrane remodeling and abscission during intraluminal vesicle (ILV) formation at endosomes. Our data now suggest that ESCRT-III function could be connected to lipid remodeling of the endosomal membrane. This notion is based on our finding that ESCRT-III proteins bind to the yeast serine incorporator (SERINC) homolog Tms1. Human SERINC3 and SERINC5 are HIV-1 restriction factors and have been shown to act as scramblases, flipping phospholipids between membrane leaflets. Due to the extraordinarily high sequence conservation between Tms1 and human SERINCs, it is likely that Tms1 is also a scramblase. While deletion of TMS1 had only a moderate effect on the sorting of multivesicular body (MVB) cargo proteins, the simultaneous deletion of a component of the Vps55/Vps68 complex led to a strong synergistic phenotype. This pronounced synergism suggests that Tms1 and Vps55/Vps68 perform a parallel function at endosomes. Vps55/Vps68 loosely resembles Tms1 in its overall structure. Thus, it is possible that Vps55/Vps68 is also a scramblase. Since both Vps55 and Tms1 physically interact with ESCRT-III proteins, we propose that the recruitment of a scramblase plays a crucial role in ESCRT-III-dependent membrane remodeling at endosomes.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Endossomos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Endossomos/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Ligação Proteica , Proteínas de Transferência de Fosfolipídeos/metabolismo , Proteínas de Transferência de Fosfolipídeos/genética , Transporte Proteico
8.
Curr Res Neurobiol ; 7: 100138, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39280771

RESUMO

The endosomal sorting complexes required for transport (ESCRT) pathway is composed of a series of protein complexes that are essential for sorting cargo through the endosome. In neurons, the ESCRT pathway is a key mediator of many cellular pathways that regulate neuronal morphogenesis as well as synaptic growth and function. The ESCRT-0 complex, consisting of HGS (hepatocyte growth factor-regulated tyrosine kinase substrate) and STAM (signal-transducing adaptor molecule), acts as a gate keeper to this pathway, ultimately determining the fate of the endosomal cargo. We previously showed that a single nucleotide substitution in Hgs results in structural and functional changes in the nervous system of teetering mice. To determine if these changes occurred as a function of HGS's role in the ESCRT pathway and its association with STAM1, we investigated if STAM1 deficiency also leads to a similar impairment of the nervous system. In contrast to teetering mice that die within 5 weeks of age and exhibit reduced body mass, 1-month-old Stam1 knockout mice were not visibly different from controls. However, by 3 months of age, STAM1 deficiency caused reduced muscle mass, strength, and motor performance. These changes in motor function did not correlate with either a loss in motor neuron number or abnormal myelination of peripheral nerves. Instead, the motor endplate structure was altered in the Stam1 knockout mice by 1 month of age and continued to degenerate over time, correlating with a significant reduction in muscle fiber size and increased expression of the embryonic γ acetylcholine receptor (AChR) subunit at 3 months of age. There was also a significant reduction in the levels of two presynaptic SNARE proteins, VTI1A and VAMP2, in the motor neurons of the Stam1 knockout mice. As loss of STAM1 expression replicates many of the structural changes at the motor endplates that we have previously reported with loss of HGS, these results suggest that the HGS/STAM1 complex plays a critical role in maintaining synaptic structure and function in the mammalian nervous system.

9.
Front Cell Dev Biol ; 12: 1451988, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286483

RESUMO

Exosomes are extracellular vesicles involved in intercellular signaling, carrying various cargo from microRNAs to metabolites and proteins. They are released by practically all cells and are highly heterogenous due to their origin and content. Several groups of exosomes are known to be involved in various pathological conditions including autoimmune, neurodegenerative, and infectious diseases as well as cancer, and therefore a substantial understanding of their biogenesis and release is crucial. Polarized cells display an array of specific functions originated from differentiated membrane trafficking systems and could lead to hints in untangling the complex process of exosomes. Indeed, recent advances have successfully revealed specific regulation pathways for releasing different subsets of exosomes from different sides of polarized epithelial cells, underscoring the importance of polarized cells in the field. Here we review current evidence on exosome biogenesis and release, especially in polarized cells, highlight the challenges that need to be combatted, and discuss potential applications related to exosomes of polarized-cell origin.

10.
Mol Cell Neurosci ; 130: 103956, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39097250

RESUMO

Microglia are immune cells that play important roles in the formation of the innate immune response within the central nervous system (CNS). The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is a multiple protein complex that is crucial for innate immunity, and excessive activation of the inflammasome for various reasons contributes to the pathogenesis of neurodegenerative diseases (NDs). ß2-adrenoceptor agonists have become the focus of attention in studies on NDs due to the high synthesis of ß2-adrenoceptors in the central nervous system (CNS). Promising results have been obtained from these studies targeting anti-inflammatory and neuroprotective effects. Formoterol is an effective, safe for long-term use, and FDA-approved ß2-adrenoceptor agonist with demonstrated anti-inflammatory features in the CNS. In this study, we researched the effects of formoterol on LPS/ATP-stimulated NLRP3 inflammasome activation, pyroptosis, NF-κB, autophagy, and ESCRT-III-mediated plasma membrane repair pathways in the N9 microglia cells. The results showed that formoterol, through the IκBα/NF-κB axis, significantly inhibited NLRP3 inflammasome activation, reduced the level of active caspase-1, secretion of IL-1ß and IL-18 proinflammatory cytokine levels, and the levels of pyroptosis. Additionally, we showed that formoterol activates autophagy, autophagosome formation, and ESCRT-III-mediated plasma membrane repair, which are significant pathways in the inhibition of NLRP3 inflammasome activation and pyroptosis. Our study suggests that formoterol efficaciously prevents the NLRP3 inflammasome activation and pyroptosis in microglial cells regulation through IκBα/NF-κB, autophagy, autophagosome formation, and ESCRT-III-mediated plasma membrane repair.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2 , Autofagia , Fumarato de Formoterol , Inflamassomos , Microglia , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Animais , Piroptose/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Fumarato de Formoterol/farmacologia , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Inibidor de NF-kappaB alfa/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Linhagem Celular
11.
J Cell Sci ; 137(18)2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39155850

RESUMO

His domain protein tyrosine phosphatase (HD-PTP; also known as PTPN23) facilitates function of the endosomal sorting complexes required for transport (ESCRTs) during multivesicular body (MVB) formation. To uncover its role in physiological homeostasis, embryonic lethality caused by a complete lack of HD-PTP was bypassed through generation of hypomorphic mice expressing reduced protein, resulting in animals that are viable into adulthood. These mice exhibited marked lipodystrophy and decreased receptor-mediated signaling within white adipose tissue (WAT), involving multiple prominent pathways including RAS/MAPK, phosphoinositide 3-kinase (PI3K)/AKT and receptor tyrosine kinases (RTKs), such as EGFR. EGFR signaling was dissected in vitro to assess the nature of defective signaling, revealing decreased trans-autophosphorylation and downstream effector activation, despite normal EGF binding. This corresponds to decreased plasma membrane cholesterol and increased lysosomal cholesterol, likely resulting from defective endosomal maturation necessary for cholesterol trafficking and homeostasis. The ESCRT components Vps4 and Hrs have previously been implicated in cholesterol homeostasis; thus, these findings expand knowledge on which ESCRT subunits are involved in cholesterol homeostasis and highlight a non-canonical role for HD-PTP in signal regulation and adipose tissue homeostasis.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Homeostase , Lipodistrofia , Proteínas Tirosina Fosfatases não Receptoras , Transdução de Sinais , Animais , Camundongos , Lipodistrofia/metabolismo , Lipodistrofia/genética , Lipodistrofia/patologia , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/genética , Colesterol/metabolismo , Metabolismo dos Lipídeos , Receptores ErbB/metabolismo , Receptores ErbB/genética , Humanos , Tecido Adiposo Branco/metabolismo
12.
Cells ; 13(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39120335

RESUMO

The endosomal sorting complex required for transport (ESCRT) machinery is composed of an articulated architecture of proteins that assemble at multiple cellular sites. The ESCRT machinery is involved in pathways that are pivotal for the physiology of the cell, including vesicle transport, cell division, and membrane repair. The subunits of the ESCRT I complex are mainly responsible for anchoring the machinery to the action site. The ESCRT II subunits function to bridge and recruit the ESCRT III subunits. The latter are responsible for finalizing operations that, independently of the action site, involve the repair and fusion of membrane edges. In this review, we report on the data related to the activity of the ESCRT machinery at two sites: the nuclear membrane and the midbody and the bridge linking cells in the final stages of cytokinesis. In these contexts, the machinery plays a significant role for the protection of genome integrity by contributing to the control of the abscission checkpoint and to nuclear envelope reorganization and correlated resilience. Consistently, several studies show how the dysfunction of the ESCRT machinery causes genome damage and is a codriver of pathologies, such as laminopathies and cancer.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Humanos , Citocinese , Animais , Membrana Nuclear/metabolismo , Instabilidade Genômica
13.
Dis Model Mech ; 17(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037280

RESUMO

Mycobacterium tuberculosis is a pathogenic mycobacterium that causes tuberculosis. Tuberculosis is a significant global health concern that poses numerous clinical challenges, particularly in terms of finding effective treatments for patients. Throughout evolution, host immune cells have developed cell-autonomous defence strategies to restrain and eliminate mycobacteria. Concurrently, mycobacteria have evolved an array of virulence factors to counteract these host defences, resulting in a dynamic interaction between host and pathogen. Here, we review recent findings, including those arising from the use of the amoeba Dictyostelium discoideum as a model to investigate key mycobacterial infection pathways. D. discoideum serves as a scalable and genetically tractable model for human phagocytes, providing valuable insights into the intricate mechanisms of host-pathogen interactions. We also highlight certain similarities between M. tuberculosis and Mycobacterium marinum, and the use of M. marinum to more safely investigate mycobacteria in D. discoideum.


Assuntos
Dictyostelium , Interações Hospedeiro-Patógeno , Mycobacterium marinum , Tuberculose , Dictyostelium/microbiologia , Mycobacterium marinum/patogenicidade , Tuberculose/microbiologia , Tuberculose/patologia , Tuberculose/imunologia , Humanos , Modelos Biológicos , Animais , Infecções por Mycobacterium não Tuberculosas
14.
Int J Mol Sci ; 25(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39062867

RESUMO

Entamoeba histolytica is the protozoan causative of human amoebiasis. The EhADH adhesin (687 aa) is a protein involved in tissue invasion, phagocytosis and host-cell lysis. EhADH adheres to the prey and follows its arrival to the multivesicular bodies. It is an accessory protein of the endosomal sorting complexes required for transport (ESCRT) machinery. Here, to study the role of different parts of EhADH during virulence events, we produced trophozoites overexpressing the three domains of EhADH, Bro1 (1-400 aa), Linker (246-446 aa) and Adh (444-687 aa) to evaluate their role in virulence. The TrophozBro11-400 slightly increased adherence and phagocytosis, but these trophozoites showed a higher ability to destroy cell monolayers, augment the permeability of cultured epithelial cells and mouse colon, and produce more damage to hamster livers. The TrophozLinker226-446 also increased the virulence properties, but with lower effect than the TrophozBro11-400. In addition, this fragment participates in cholesterol transport and GTPase binding. Interestingly, the TrophozAdh444-687 produced the highest effect on adherence and phagocytosis, but it poorly influenced the monolayers destruction; nevertheless, they augmented the colon and liver damage. To identify the protein partners of each domain, we used recombinant peptides. Pull-down assays and mass spectrometry showed that Bro1 domain interplays with EhADH, Gal/GalNAc lectin, EhCPs, ESCRT machinery components and cytoskeleton proteins. While EhADH, ubiquitin, EhRabB, EhNPC1 and EhHSP70 were associated to the Linker domain, and EhADH, EhHSP70, EhPrx and metabolic enzymes interacted to the Adh domain. The diverse protein association confirms that EhADH is a versatile molecule with multiple functions probably given by its capacity to form distinct molecular complexes.


Assuntos
Entamoeba histolytica , Proteínas de Protozoários , Entamoeba histolytica/patogenicidade , Entamoeba histolytica/metabolismo , Animais , Camundongos , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Humanos , Virulência , Fagocitose , Domínios Proteicos , Entamebíase/parasitologia , Entamebíase/metabolismo , Cricetinae , Trofozoítos/metabolismo
15.
Viruses ; 16(7)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39066286

RESUMO

The BK polyomavirus (BKPyV) is a small DNA non-enveloped virus whose infection is asymptomatic in most of the world's adult population. However, in cases of immunosuppression, the reactivation of the virus can cause various complications, and in particular, nephropathies in kidney transplant recipients or hemorrhagic cystitis in bone marrow transplant recipients. Recently, it was demonstrated that BKPyV virions can use extracellular vesicles to collectively traffic in and out of cells, thus exiting producing cells without cell lysis and entering target cells by diversified entry routes. By a comparison to other naked viruses, we investigated the possibility that BKPyV virions recruit the Endosomal-Sorting Complexes Required for Transport (ESCRT) machinery through late domains in order to hijack extracellular vesicles. We identified a single potential late domain in the BKPyV structural proteins, a YPX3L motif in the VP1 protein, and used pseudovirions to study the effect of point mutations found in a BKPyV clinical isolate or known to ablate the interaction of such a domain with the ESCRT machinery. Our results suggest that this domain is not involved in BKPyV association with extracellular vesicles but is crucial for capsomere interaction and thus viral particle assembly.


Assuntos
Motivos de Aminoácidos , Vírus BK , Proteínas do Capsídeo , Vesículas Extracelulares , Vírion , Montagem de Vírus , Vírus BK/genética , Vírus BK/fisiologia , Vírus BK/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/virologia , Humanos , Proteínas do Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/química , Vírion/metabolismo , Vírion/genética , Infecções por Polyomavirus/virologia , Infecções por Polyomavirus/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Células HEK293
16.
Cells ; 13(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39056756

RESUMO

Members of the LGD/CC2D1 protein family contain repeats of the family-defining DM14 domains. Via this domain, they interact with members of the CHMP family, which are essential for the ESCRT machinery-mediated formation of intraluminal vesicles during endosome maturation. Here, we investigate the requirement of the DM14 domains for the function of Lgd in detail. We found that although both odd-numbered DM14s can act in a functionally redundant manner, the redundancy is not complete and both contribute to the full function of Lgd. Our analysis indicates that some of the AAs that form the KARRxxR motif of the onDM14s are not exchangeable by similarly charged AAs without loss of function, indicating that they not only provide charge, but also fulfil structural roles. Furthermore, we show that the region of Lgd between DM14-4 and the C2 domain as well as its C-terminal region to the C2 domain are important for protein stability/function. Moreover, we analysed the importance of AAs that are conserved in all DM14 domains. Finally, our analysis of the C. elegans ortholog of Lgd revealed that it has only one DM14 domain that is functionally equivalent to the onDM14s. Altogether, the results further the understanding of how Lgd family members regulate the ESCRT machinery.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Animais , Sequência de Aminoácidos , Caenorhabditis elegans , Drosophila melanogaster , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Domínios Proteicos
17.
Mol Cell Biochem ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970706

RESUMO

Alzheimer's disease (AD) progression is closely linked to the propagation of pathological Amyloid ß (Aß), a process increasingly understood to involve extracellular vesicles (EVs), namely exosomes. The specifics of Aß packaging into exosomes remain elusive, although evidence suggests an ESCRT (Endosomal Sorting Complex Required for Transport)-independent origin to be responsible in spreading of AD pathogenesis. Intriguingly, PrPC, known to influence exosome abundance and bind oligomeric Aß (oAß), can be released in exosomes via both ESCRT-dependent and ESCRT-independent pathways, raising questions about its role in oAß trafficking. Thus, we quantified Aß levels within EVs, cell medium, and intracellularly, alongside exosome biogenesis-related proteins, following deletion or overexpression of PrPC. The same parameters were also evaluated in the presence of specific exosome inhibitors, namely Manumycin A and GW4869. Our results revealed that deletion of PrPC increases intracellular Aß accumulation and amplifies EV abundance, alongside significant changes in cellular levels of exosome biogenesis-related proteins Vps25, Chmp2a, and Rab31. In contrast, cellular expression of PrPC did not alter exosomal Aß levels. This highlights PrPC's influence on exosome biogenesis, albeit not in direct Aß packaging. Additionally, our data confirm the ESCRT-independent exosome release of Aß and we show a direct reduction in Chmp2a levels upon oAß challenge. Furthermore, inhibition of opposite exosome biogenesis pathway resulted in opposite cellular PrPC levels. In conclusion, our findings highlight the intricate relationship between PrPC, exosome biogenesis, and Aß release. Specifically, they underscore PrPC's critical role in modulating exosome-associated proteins, EV abundance, and cellular Aß levels, thereby reinforcing its involvement in AD pathogenesis.

18.
Front Cell Infect Microbiol ; 14: 1418168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988816

RESUMO

Exosomes are extracelluar vesicles that facilitate intercellular communication and are pivotal in post-transcriptional regulation within cellular gene regulatory networks, impacting pathogen dynamics. These vesicles serve as crucial regulators of immune responses, mediating cellular interactions and enabling the introduction of viral pathogenic regions into host cells. Exosomes released from virus-infected cells harbor diverse microRNAs (miRNAs), which can be transferred to recipient cells, thereby modulating virus infection. This transfer is a critical element in the molecular interplay mediated by exosomes. Additionally, the endosomal sorting complex required for transport (ESCRT) within exosomes plays a vital role in virus infection, with ESCRT components binding to viral proteins to facilitate virus budding. This review elucidates the roles of exosomes and their constituents in the invasion of host cells by viruses, aiming to shed new light on the regulation of viral transmission via exosomes.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte , Exossomos , Interações Hospedeiro-Patógeno , MicroRNAs , Viroses , Exossomos/metabolismo , Humanos , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Viroses/metabolismo , Viroses/virologia , MicroRNAs/metabolismo , MicroRNAs/genética , Animais , Vírus/patogenicidade , Vírus/metabolismo , Liberação de Vírus , Proteínas Virais/metabolismo , Proteínas Virais/genética
19.
Front Microbiol ; 15: 1431672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015737

RESUMO

Alphaherpesvirus is a widespread pathogen that causes diverse diseases in humans and animals and can severely damage host health. Alphaherpesvirus particles comprise a DNA core, capsid, tegument and envelope; the tegument is located between the nuclear capsid and envelope. According to biochemical and proteomic analyses of alphaherpesvirus particles, the tegument contains at least 24 viral proteins and plays an important role in the alphaherpesvirus life cycle. This article reviews the important role of tegument proteins and their interactions during the viral life cycle to provide a reference and inspiration for understanding alphaherpesvirus infection pathogenesis and identifying new antiviral strategies.

20.
Anim Cells Syst (Seoul) ; 28(1): 367-380, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39070887

RESUMO

The endosomal sorting complexes required for transport (ESCRT) machinery is an evolutionarily conserved cytosolic protein complex that plays a crucial role in membrane remodeling and scission events across eukaryotes. Initially discovered for its function in multivesicular body (MVB) formation, the ESCRT complex has since been implicated in a wide range of membrane-associated processes, including endocytosis, exocytosis, cytokinesis, and autophagy. Recent advances have elucidated the ESCRT assembly pathway and highlighted the distinct functions of the various ESCRT complexes and their associated partners. Among the ESCRT complexes, ESCRT-III stands out as a critical player in membrane remodeling, with its subunits assembled into higher-order multimers capable of bending and severing membranes. This review focuses on the ESCRT-III complex, exploring its diverse functions in cellular processes beyond MVB biogenesis. We delve into the molecular mechanisms underlying ESCRT-III-mediated membrane remodeling and highlight its emerging roles in processes such as viral budding, autophagosome closure, and cytokinetic abscission. We also discuss the implications of ESCRT-III dysregulation in neurodegenerative diseases. The versatile membrane remodeling capabilities of ESCRT-III across diverse cellular processes underscore its importance in maintaining proper cellular function. Furthermore, we highlight the promising potential of ESCRT-III as a therapeutic target for neurodegenerative diseases, offering insights into the treatments of the diseases and the technical applications in related research fields.

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