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1.
Physiol Rep ; 12(8): e16008, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38631890

RESUMEN

We executed this study to determine if chemerin-like receptor 1 (CMKLR1), a Gi/o protein-coupled receptor expressed by leukocytes and non-leukocytes, contributes to the development of phenotypic features of non-atopic asthma, including airway hyperresponsiveness (AHR) to acetyl-ß-methylcholine chloride, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Accordingly, we quantified sequelae of non-atopic asthma in wild-type mice and mice incapable of expressing CMKLR1 (CMKLR1-deficient mice) following cessation of acute inhalation exposure to either filtered room air (air) or ozone (O3), a criteria pollutant and non-atopic asthma stimulus. Following exposure to air, lung elastic recoil and airway responsiveness were greater while the quantity of adiponectin, a multi-functional adipocytokine, in bronchoalveolar lavage (BAL) fluid was lower in CMKLR1-deficient as compared to wild-type mice. Regardless of genotype, exposure to O3 caused AHR, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Nevertheless, except for minimal genotype-related effects on lung hyperpermeability and BAL adiponectin, we observed no other genotype-related differences following O3 exposure. In summary, we demonstrate that CMKLR1 limits the severity of innate airway responsiveness and lung elastic recoil but has a nominal effect on lung pathophysiology induced by acute exposure to O3.


Asunto(s)
Asma , Ozono , Neumonía , Animales , Ratones , Masculino , Ozono/efectos adversos , Adiponectina/farmacología , Pulmón , Neumonía/inducido químicamente , Líquido del Lavado Bronquioalveolar , Receptores Acoplados a Proteínas G , Asma/genética , Quimiocinas/farmacología , Péptidos y Proteínas de Señalización Intercelular/farmacología
2.
Nat Rev Microbiol ; 22(5): 309-321, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38102460

RESUMEN

Autophagy is a constitutive cellular process of degradation required to maintain homeostasis and turn over spent organelles and aggregated proteins. For some viruses, the process can be antiviral, degrading viral proteins or virions themselves. For many other viruses, the induction of the autophagic process provides a benefit and promotes viral replication. In this Review, we survey the roles that the autophagic pathway plays in the replication of viruses. Most viruses that benefit from autophagic induction block autophagic degradation, which is a 'bend, but don't break' strategy initiating but limiting a potentially antiviral response. In almost all cases, it is other effects of the redirected autophagic machinery that benefit these viruses. This rapid mechanism to generate small double-membraned vesicles can be usurped to shape membranes for viral genome replication and virion maturation. However, data suggest that autophagic maintenance of cellular homeostasis is crucial for the initiation of infection, as viruses have evolved to replicate in normal, healthy cells. Inhibition of autophagic degradation is important once infection has initiated. Although true degradative autophagy is probably a negative for most viruses, initiating nondegradative autophagic membranes benefits a wide variety of viruses.


Asunto(s)
Virus , Proteínas Virales , Virión , Autofagia/fisiología , Antivirales , Replicación Viral
3.
Elife ; 122023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37850626

RESUMEN

Enterovirus D68 (EV-D68) is a re-emerging enterovirus that causes acute respiratory illness in infants and has recently been linked to Acute Flaccid Myelitis. Here, we show that the histone deacetylase, SIRT-1, is essential for autophagy and EV-D68 infection. Knockdown of SIRT-1 inhibits autophagy and reduces EV-D68 extracellular titers. The proviral activity of SIRT-1 does not require its deacetylase activity or functional autophagy. SIRT-1's proviral activity is, we demonstrate, mediated through the repression of endoplasmic reticulum stress (ER stress). Inducing ER stress through thapsigargin treatment or SERCA2A knockdown in SIRT-1 knockdown cells had no additional effect on EV-D68 extracellular titers. Knockdown of SIRT-1 also decreases poliovirus and SARS-CoV-2 titers but not coxsackievirus B3. In non-lytic conditions, EV-D68 is primarily released in an enveloped form, and SIRT-1 is required for this process. Our data show that SIRT-1, through its translocation to the cytosol, is critical to promote the release of enveloped EV-D68 viral particles.


Asunto(s)
Enterovirus Humano D , Infecciones por Enterovirus , Sirtuina 1 , Activación Viral , Humanos , COVID-19 , Enterovirus/genética , Enterovirus/fisiología , Enterovirus Humano D/genética , Enterovirus Humano D/fisiología , Infecciones por Enterovirus/genética , Infecciones por Enterovirus/fisiopatología , Enfermedades Neuromusculares , Provirus , SARS-CoV-2 , Envoltura Viral/metabolismo , Envoltura Viral/fisiología , Activación Viral/genética , Activación Viral/fisiología , Sirtuina 1/genética , Sirtuina 1/fisiología
4.
mBio ; 14(5): e0214123, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37819109

RESUMEN

IMPORTANCE: The respiratory picornavirus enterovirus D68 is a causative agent of acute flaccid myelitis, a childhood paralysis disease identified in the last decade. Poliovirus, another picornavirus associated with paralytic disease, is a fecal-oral virus that survives acidic environments when passing from host to host. Here, we follow up on our previous work showing a requirement for acidic intracellular compartments for maturation cleavage of poliovirus particles. Enterovirus D68 requires acidic vesicles for an earlier step, assembly, and maintenance of viral particles themselves. These data have strong implications for the use of acidification blocking treatments to combat enterovirus diseases.


Asunto(s)
Enterovirus Humano D , Infecciones por Enterovirus , Mielitis , Enfermedades Neuromusculares , Poliovirus , Humanos , Niño , Enterovirus Humano D/genética , Cápside
5.
bioRxiv ; 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37398138

RESUMEN

Enterovirus D68 (EV-D68), a picornavirus traditionally associated with respiratory infections, has recently been linked to a polio-like paralytic condition known as acute flaccid myelitis (AFM). EV-D68 is understudied, and much of the field's understanding of this virus is based on studies of poliovirus. For poliovirus, we previously showed that low pH promotes virus capsid maturation, but here we show that, for EV-D68, inhibition of compartment acidification during a specific window of infection causes a defect in capsid formation and maintenance. These phenotypes are accompanied by radical changes in the infected cell, with viral replication organelles clustering in a tight juxtanuclear grouping. Organelle acidification is critical during a narrow window from 3-4hpi, which we have termed the "transition point," separating translation and peak RNA replication from capsid formation, maturation and egress. Our findings highlight that acidification is crucial only when vesicles convert from RNA factories to virion crucibles.

6.
Autophagy ; 19(4): 1049-1054, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36628432

RESUMEN

In this editors' corner, the section editors were asked to indicate where they see the autophagy field heading and to suggest what they consider to be key unanswered questions in their specialty area.


Asunto(s)
Autofagia , Investigación Biomédica , Investigación Biomédica/tendencias
7.
Ann N Y Acad Sci ; 1521(1): 46-66, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36697369

RESUMEN

Positive-strand RNA viruses have been the cause of several recent outbreaks and epidemics, including the Zika virus epidemic in 2015, the SARS outbreak in 2003, and the ongoing SARS-CoV-2 pandemic. On June 18-22, 2022, researchers focusing on positive-strand RNA viruses met for the Keystone Symposium "Positive-Strand RNA Viruses" to share the latest research in molecular and cell biology, virology, immunology, vaccinology, and antiviral drug development. This report presents concise summaries of the scientific discussions at the symposium.


Asunto(s)
COVID-19 , Infección por el Virus Zika , Virus Zika , Humanos , SARS-CoV-2 , Virus ARN Monocatenarios Positivos , Antivirales/uso terapéutico , Pandemias , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/prevención & control , Infección por el Virus Zika/tratamiento farmacológico
8.
Virology ; 578: 117-127, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36527930

RESUMEN

Picornaviruses rearrange host cell membranes to facilitate their own replication. Here we investigate the Qbc SNARE, SNAP23, which is found at the plasma membrane and plays roles in exocytosis. We found that knockdown of SNAP23 expression inhibits virus replication but not release from cells. Knocking down SNAP23 inhibits viral RNA replication and synthesis of structural proteins. Normal cellular levels of SNAP23 are required for an early step in virus production, prior to or at the stage of virus RNA replication. We report that SNAP23 knockdown generates large, electron-light structures, and that infection of cells with these structures does not alter them, and those cells fail to generate viral RNA replication sites. We suggest that SNAP23 may play a role in maintaining membranes and lipids needed for generating virus replication organelles. Further investigation is needed to determine the precise role of this crucial SNARE protein in EV-D68 replication.


Asunto(s)
Enterovirus Humano D , Línea Celular , Membrana Celular/metabolismo , Enterovirus Humano D/genética , Fusión de Membrana , Orgánulos , Replicación Viral
9.
Autophagy ; 19(1): 112-125, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35446171

RESUMEN

Enterovirus D68 (EV-D68) is a respiratory pathogen associated with acute flaccid myelitis, a childhood paralysis disease. No approved vaccine or antiviral treatment exists against EV-D68. Infection with this virus induces the formation of autophagosomes to enhance its replication but blocks the downstream autophagosome- lysosome fusion steps. Here, we examined the impact of autophagy induction through starvation, either before (starvation before infection, SBI) or after (starvation after infection, SAI) EV-D68 infection. We showed that SAI, but not SBI, attenuated EV-D68 replication in multiple cell lines and abrogated the viral-mediated cleavage of host autophagic flux-related proteins. Furthermore, SAI induced autophagic flux during EV-D68 replication and prevented production of virus-induced membranes, which are required for picornavirus replication. Pharmacological inhibition of autophagic flux during SAI did not rescue EV-D68 titers. SAI had the same effect in multiple cell types, and restricted the replication of several medically relevant picornaviruses. Our results highlight the significance of autophagosomes for picornavirus replication and identify SAI as an attractive broad-spectrum anti-picornavirus strategy.Abbreviations: BAF: bafilomycin A1; CCCP: carbonyl cyanide m-chlorophenylhydrazone; CQ: chloroquine; CVB3: coxsackievirus B3; EV-D68: enterovirus D68; hpi: hour post-infection; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MOI: multiplicity of infection; NSP2B: nonstructural protein 2B; PV: poliovirus; RES: resveratrol; RV14: rhinovirus 14; SAI: starvation after infection; SBI: starvation before infection; SNAP29: synaptosome associated protein 29; SQSTM1/p62: sequestosome 1; TFEB: transcription factor EB.


Asunto(s)
Enterovirus Humano D , Infecciones por Enterovirus , Mielitis , Humanos , Autofagia , Proteínas Relacionadas con la Autofagia , Línea Celular
10.
Am J Physiol Regul Integr Comp Physiol ; 323(6): R921-R934, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36283092

RESUMEN

Interleukin (IL)-11, a multifunctional cytokine, contributes to numerous biological processes, including adipogenesis, hematopoiesis, and inflammation. Asthma, a respiratory disease, is notably characterized by reversible airway obstruction, persistent lung inflammation, and airway hyperresponsiveness (AHR). Nasal insufflation of IL-11 causes AHR in wild-type mice while lung inflammation induced by antigen sensitization and challenge, which mimics features of atopic asthma in humans, is attenuated in mice genetically deficient in IL-11 receptor subunit α-1 (IL-11Rα1-deficient mice), a transmembrane receptor that is required conjointly with glycoprotein 130 to transduce IL-11 signaling. Nevertheless, the contribution of IL-11Rα1 to characteristics of nonatopic asthma is unknown. Thus, based on the aforementioned observations, we hypothesized that genetic deficiency of IL-11Rα1 attenuates lung inflammation and increases airway responsiveness after acute inhalation exposure to ozone (O3), a criteria pollutant and nonatopic asthma stimulus. Accordingly, 4 and/or 24 h after cessation of exposure to filtered room air or O3, we assessed lung inflammation and airway responsiveness in wild-type and IL-11Rα1-deficient mice. With the exception of bronchoalveolar lavage macrophages and adiponectin, which were significantly increased and decreased, respectively, in O3-exposed IL-11Rα1-deficient as compared with O3-exposed wild-type mice, no other genotype-related differences in lung inflammation indices that we quantified were observed in O3-exposed mice. However, airway responsiveness to acetyl-ß-methylcholine chloride (methacholine) was significantly diminished in IL-11Rα1-deficient as compared with wild-type mice after O3 exposure. In conclusion, these results demonstrate that IL-11Rα1 minimally contributes to lung inflammation but is required for maximal airway responsiveness to methacholine in a mouse model of nonatopic asthma.


Asunto(s)
Asma , Ozono , Neumonía , Humanos , Ratones , Animales , Cloruro de Metacolina/efectos adversos , Ozono/toxicidad , Interleucina-11/efectos adversos , Asma/genética , Neumonía/inducido químicamente , Neumonía/genética , Neumonía/complicaciones , Receptores de Interleucina-11 , Líquido del Lavado Bronquioalveolar
11.
Autophagy ; 16(12): 2131-2139, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32964796

RESUMEN

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is the most recent example of an emergent coronavirus that poses a significant threat to human health. Virus-host interactions play a major role in the viral life cycle and disease pathogenesis, and cellular pathways such as macroautophagy/autophagy prove to be either detrimental or beneficial to viral replication and maturation. Here, we describe the literature over the past twenty years describing autophagy-coronavirus interactions. There is evidence that many coronaviruses induce autophagy, although some of these viruses halt the progression of the pathway prior to autophagic degradation. In contrast, other coronaviruses usurp components of the autophagy pathway in a non-canonical fashion. Cataloging these virus-host interactions is crucial for understanding disease pathogenesis, especially with the global challenge of SARS-CoV-2 and COVID-19. With the recognition of autophagy inhibitors, including the controversial drug chloroquine, as possible treatments for COVID-19, understanding how autophagy affects the virus will be critical going forward. Abbreviations: 3-MA: 3-methyladenine (autophagy inhibitor); AKT/protein kinase B: AKT serine/threonine kinase; ATG: autophagy related; ATPase: adenosine triphosphatase; BMM: bone marrow macrophage; CGAS: cyclic GMP-AMP synthase; CHO: Chinese hamster ovary/cell line; CoV: coronaviruses; COVID-19: Coronavirus disease 2019; DMV: double-membrane vesicle; EAV: equine arteritis virus; EDEM1: ER degradation enhancing alpha-mannosidase like protein 1; ER: endoplasmic reticulum; ERAD: ER-associated degradation; GFP: green fluorescent protein; HCoV: human coronavirus; HIV: human immunodeficiency virus; HSV: herpes simplex virus; IBV: infectious bronchitis virus; IFN: interferon; LAMP1: lysosomal associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCoV: mouse coronavirus; MERS-CoV: Middle East respiratory syndrome coronavirus; MHV: mouse hepatitis virus; NBR1: NBR1 autophagy cargo receptor; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2 (autophagy receptor that directs cargo to phagophores); nsp: non-structural protein; OS9: OS9 endoplasmic reticulum lectin; PEDV: porcine epidemic diarrhea virus; PtdIns3K: class III phosphatidylinositol 3-kinase; PLP: papain-like protease; pMEF: primary mouse embryonic fibroblasts; SARS-CoV: severe acute respiratory syndrome coronavirus; SKP2: S-phase kinase associated protein 2; SQSTM1: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; ULK1: unc-51 like autophagy activating kinase 1; Vps: vacuolar protein sorting.


Asunto(s)
Autofagia/fisiología , Infecciones por Coronavirus/inmunología , Coronavirus/inmunología , Animales , Proteína 5 Relacionada con la Autofagia/fisiología , Células CHO , COVID-19/epidemiología , COVID-19/patología , COVID-19/virología , Coronavirus/patogenicidad , Coronavirus/fisiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Cricetinae , Cricetulus , Humanos , Ratones , Pandemias , SARS-CoV-2/inmunología , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Transducción de Señal/fisiología
12.
Sci Rep ; 10(1): 7939, 2020 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-32409751

RESUMEN

Enteroviruses support cell-to-cell viral transmission prior to their canonical lytic spread of virus. Poliovirus (PV), a prototype for human pathogenic positive-sense RNA enteroviruses, and picornaviruses in general, transport multiple virions en bloc via infectious extracellular vesicles, 100~1000 nm in diameter, secreted from host cells. Using biochemical and biophysical methods we identify multiple components in secreted microvesicles, including mature PV virions; positive-sense genomic and negative-sense replicative, template viral RNA; essential viral replication proteins; and cellular proteins. Using cryo-electron tomography, we visualize the near-native three-dimensional architecture of secreted infectious microvesicles containing both virions and a unique morphological component that we describe as a mat-like structure. While the composition of these mat-like structures is not yet known, based on our biochemical data they are expected to be comprised of unencapsidated RNA and proteins. In addition to infectious microvesicles, CD9-positive exosomes released from PV-infected cells are also infectious and transport virions. Thus, our data show that, prior to cell lysis, non-enveloped viruses are secreted within infectious vesicles that also transport viral unencapsidated RNAs, viral and host proteins. Understanding the structure and function of these infectious particles helps elucidate the mechanism by which extracellular vesicles contribute to the spread of non-enveloped virus infection.


Asunto(s)
Vesículas Extracelulares/ultraestructura , Vesículas Extracelulares/virología , Poliovirus/fisiología , Células HeLa , Humanos , Poliovirus/genética , ARN Viral/metabolismo
13.
Mucosal Immunol ; 12(4): 958-968, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31089187

RESUMEN

Activation of the inflammasome is a key function of the innate immune response that regulates inflammation in response to microbial substances. Inflammasome activation by human rhinovirus (RV), a major cause of asthma exacerbations, has not been well studied. We examined whether RV induces inflammasome activation in vivo, molecular mechanisms underlying RV-stimulated inflammasome priming and activation, and the contribution of inflammasome activation to RV-induced airway inflammation and exacerbation. RV infection triggered lung mRNA and protein expression of pro-IL-1ß and NLRP3, indicative of inflammasome priming, as well as cleavage of caspase-1 and pro-IL-1ß, completing inflammasome activation. Immunofluorescence staining showed IL-1ß in lung macrophages. Depletion with clodronate liposomes and adoptive transfer experiments showed macrophages to be required and sufficient for RV-induced inflammasome activation. TLR2 was required for RV-induced inflammasome priming in vivo. UV irradiation blocked inflammasome activation and RV genome was sufficient for inflammasome activation in primed cells. Naive and house dust mite-treated NLRP3-/- and IL-1ß-/- mice, as well as IL-1 receptor antagonist-treated mice, showed attenuated airway inflammation and responsiveness following RV infection. We conclude that RV-induced inflammasome activation is required for maximal airway inflammation and hyperresponsiveness in naive and allergic mice. The inflammasome represents a molecular target for RV-induced asthma exacerbations.


Asunto(s)
Alérgenos/inmunología , Inflamasomas/metabolismo , Infecciones por Picornaviridae/inmunología , Infecciones por Picornaviridae/metabolismo , Infecciones del Sistema Respiratorio/inmunología , Infecciones del Sistema Respiratorio/metabolismo , Rhinovirus/inmunología , Animales , Modelos Animales de Enfermedad , Humanos , Inmunización , Interleucina-1beta/genética , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Infecciones por Picornaviridae/virología , Pyroglyphidae/inmunología , Infecciones del Sistema Respiratorio/virología , Rhinovirus/genética , Receptor Toll-Like 2/metabolismo
14.
Med Clin North Am ; 103(2): 251-261, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30704680

RESUMEN

Concussion is a public health crisis affecting vulnerable populations including youth athletes. As awareness increases, more patients with acute concussion are seeking medical evaluations. Internists are frontline medical providers and thus should be able to identify, diagnose, manage, and know when to refer patients with concussion. Management of concussion includes rapid removal from play, symptomatic treatment, and return to learn/play recommendations. Inappropriate management may lead to recurrent concussions, prolonged recovery, and potential long-term consequences. Understanding the key features of diagnosis, postinjury assessment tools, symptomatic treatment, and management of concussion, including return to learn/play recommendations, is essential for primary care providers.


Asunto(s)
Conmoción Encefálica/diagnóstico , Conmoción Encefálica/terapia , Cefalea/terapia , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/rehabilitación , Conmoción Encefálica/complicaciones , Cefalea/etiología , Humanos
15.
Neurologist ; 24(1): 44-47, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30586036

RESUMEN

Mechanical thrombectomy (MT) is the standard of care for patients who present with an acute ischemic stroke within 6 hours of symptom onset, and up to 24 hours in appropriately selected patients. However, optimal postoperative management of these patients remains uncertain, especially with regard to blood pressure control. To review the existing literature to define potential blood pressure goals in the immediate postoperative period in patients who undergo MT for acute ischemic stroke. The topic was defined through a clinical scenario and the subsequent development of a targeted clinical question. A literature search was performed, with relevant articles selected, one of which, a prospective observational study, was critically appraised. Participants included neurology residents and consultants, a medical librarian, clinical epidemiologists, as well as content experts from vascular neurology and interventional neuroradiology. Permissive hypertension (defined as <220/120 or <180/105 mm Hg as per the American Heart Association/American Stroke Association guidelines) may be harmful in the postoperative period following MT, especially in patients who were successfully recanalized. Moderate blood pressure control (<160/90) was found to be a predictor of improved 3-month mortality on multivariable logistic regression analysis in patients who sustained successful reperfusion [odds ratio (OR), 0.08; 95% confidence interval (CI), 0.01-0.054; P=0.01]. A 10 mm Hg increase in systolic blood pressure was found to result in a lower OR of having a favorable 3-month functional independence (OR, 0.70; 95% CI, 0.56-0.85; P=0.001) as well as higher rates of 3-month mortality (OR, 1.49; 95% CI, 1.18-1.88; P=0.001). Blood pressure goals in the immediate postoperative period in patients who undergo MT should differ than those who do not undergo MT, with data suggesting that lower blood pressure than permissive hypertension may be related to improved outcomes, especially in cases of successful reperfusion. However, current data are derived from observational studies; further studies, preferably in the form of randomized-controlled trials, are needed to further clarify the relationship between postoperative blood pressures and outcomes in this patient population.


Asunto(s)
Presión Sanguínea/fisiología , Isquemia Encefálica/complicaciones , Trombolisis Mecánica/métodos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/cirugía , Anciano de 80 o más Años , Femenino , Humanos , Resultado del Tratamiento
16.
Trends Cell Biol ; 28(11): 869-881, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30115558

RESUMEN

Autophagosome/amphisome-lysosome fusion is a highly regulated process at the protein, lipid, and biochemical level. Each primary component of fusion, such as the core SNAREs, HOPS complex, or physical positioning by microtubule-associated dynein motors, are regulated at multiple points to ensure optimum conditions for autophagic flux to proceed. With the complexity of the membrane fusion system, it is not difficult to imagine how autophagic flux defect-related disorders, such as Huntington's disease, non-familial Alzheimer's disease, and Vici syndrome develop. Each membrane fusion step is regulated at the protein, lipid, and ion level. This review aims to discuss the recent developments toward understanding the regulation of autophagosome, amphisome, and lysosome fusion requirements for successful autophagic flux.


Asunto(s)
Autofagosomas/metabolismo , Autofagia , Lisosomas/metabolismo , Animales , Humanos
17.
JCI Insight ; 3(16)2018 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-30135310

RESUMEN

Enterovirus D68 (EV-D68) shares biologic features with rhinovirus (RV). In 2014, a nationwide outbreak of EV-D68 was associated with severe asthma-like symptoms. We sought to develop a mouse model of EV-D68 infection and determine the mechanisms underlying airway disease. BALB/c mice were inoculated intranasally with EV-D68 (2014 isolate), RV-A1B, or sham, alone or in combination with anti-IL-17A or house dust mite (HDM) treatment. Like RV-A1B, lung EV-D68 viral RNA peaked 12 hours after infection. EV-D68 induced airway inflammation, expression of cytokines (TNF-α, IL-6, IL-12b, IL-17A, CXCL1, CXCL2, CXCL10, and CCL2), and airway hyperresponsiveness, which were suppressed by anti-IL-17A antibody. Neutrophilic inflammation and airway responsiveness were significantly higher after EV-D68 compared with RV-A1B infection. Flow cytometry showed increased lineage-, NKp46-, RORγt+ IL-17+ILC3s and γδ T cells in the lungs of EV-D68-treated mice compared with those in RV-treated mice. EV-D68 infection of HDM-exposed mice induced additive or synergistic increases in BAL neutrophils and eosinophils and expression of IL-17, CCL11, IL-5, and Muc5AC. Finally, patients from the 2014 epidemic period with EV-D68 showed significantly higher nasopharyngeal IL-17 mRNA levels compared with patients with RV-A infection. EV-D68 infection induces IL-17-dependent airway inflammation and hyperresponsiveness, which is greater than that generated by RV-A1B, consistent with the clinical picture of severe asthma-like symptoms.


Asunto(s)
Asma/inmunología , Enterovirus Humano D/inmunología , Infecciones por Enterovirus/inmunología , Interleucina-17/metabolismo , Neutrófilos/inmunología , Alérgenos/administración & dosificación , Alérgenos/inmunología , Animales , Asma/patología , Asma/virología , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Línea Celular Tumoral , Niño , Preescolar , Modelos Animales de Enfermedad , Enterovirus/inmunología , Enterovirus/aislamiento & purificación , Enterovirus Humano D/aislamiento & purificación , Infecciones por Enterovirus/patología , Infecciones por Enterovirus/virología , Femenino , Humanos , Lactante , Recién Nacido , Interleucina-17/antagonistas & inhibidores , Interleucina-17/genética , Interleucina-17/inmunología , Pulmón/citología , Pulmón/patología , Masculino , Ratones , Nasofaringe/inmunología , Nasofaringe/patología , Nasofaringe/virología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Pyroglyphidae/inmunología , ARN Mensajero/metabolismo
18.
Mol Cell Biol ; 38(21)2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30126896

RESUMEN

Autophagy is an evolutionary conserved, degradative process from single-cell eukaryotes, such as Saccharomyces cerevisiae, to higher mammals, such as humans. The regulation of autophagy has been elucidated through the combined study of yeast, Caenorhabditis elegans, mice, Drosophila melanogaster, and humans. MTOR, the major negative regulator of autophagy, and activating nutrient kinases, such as 5'-AMP-activated protein kinase (AMPK), interact with the autophagy regulatory complex: ULK1/2, RB1CC1, ATG13, and ATG101. The ULK1/2 complex induces autophagy by phosphorylating downstream autophagy complexes, such as the BECN1 PIK3 signaling complex that leads to the creation of LC3+ autophagosomes. We highlight in this review various reports of autophagy induction that are independent of these regulators. We discuss reports of MTOR-independent, AMPK-independent, ULK1/2-independent, and BECN1-PIK3C3-independent autophagy. We illustrate that autophagy induction and the components required vary by the nature of the induction signal and type of cell and do not always require canonical members of the autophagy signaling pathway. We illustrate that rather than thinking of autophagy as a linear pathway, it is better to think of autophagy induction as an interconnecting web of key regulators, many of which can induce autophagy through different requirements depending on the type and length of induction signals.


Asunto(s)
Autofagia/fisiología , Transducción de Señal/fisiología , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Beclina-1/metabolismo , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Humanos , Proteínas Serina-Treonina Quinasas/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
19.
Autophagy ; 14(8): 1469-1471, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30032704

RESUMEN

Picornaviruses, one of the major causes of human diseases ranging from the common cold to acute flaccid paralysis, have a short cytosolic lifecycle that, in cultured cells, ends in cell lysis. For years, the prevailing model was that these viruses exit from cells exclusively through cell lysis. However, over the last several years it has become apparent that for some picornaviruses, a macroautophagy/autophagy-related pathway can result in release of virus particles wrapped in a membrane containing autophagic markers. It has been proposed that this enveloped release predominates within hosts, allowing cell-to-cell movement of virus while minimizing exposure to the immune system. One reason that picornaviruses induce the autophagy pathway is to provide membrane scaffolds for RNA replication complexes. Perhaps more importantly, acidified autophagosomes (known as amphisomes) provide havens for maturation of new viral particles into infectious viruses. In back-to-back papers recently published in Cell Reports, our labs investigated a basic question: if picornavirus particles are maturing inside amphisomes, then how are they avoiding the typical degradative fate of autophagic cargo and exiting the cell intact?


Asunto(s)
Autofagia , Enterovirus , Autofagosomas , Humanos , Replicación Viral
20.
Autophagy ; 14(7): 1201-1213, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29929428

RESUMEN

Poliovirus (PV), like many positive-strand RNA viruses, subverts the macroautophagy/autophagy pathway to promote its own replication. Here, we investigate whether the virus uses the canonical autophagic signaling complex, consisting of the ULK1/2 kinases, ATG13, RB1CC1, and ATG101, to activate autophagy. We find that the virus sends autophagic signals independent of the ULK1 complex, and that the members of the autophagic complex are not required for normal levels of viral replication. We also show that the SQSTM1/p62 receptor protein is not degraded in a conventional manner during infection, but is likely cleaved in a manner similar to that shown for coxsackievirus B3. This means that SQSTM1, normally used to monitor autophagic degradation, cannot be used to accurately monitor degradation during poliovirus infection. In fact, autophagic degradation may be affected by the loss of SQSTM1 at the same time as autophagic signals are being sent. Finally, we demonstrate that ULK1 and ULK2 protein levels are greatly reduced during PV infection, and ATG13, RB1CC1, and ATG101 protein levels are reduced as well. Surprisingly, autophagic signaling appears to increase as ULK1 levels decrease. Overexpression of wild-type or dominant-negative ULK1 constructs does not affect virus replication, indicating that ULK1 degradation may be a side effect of the ULK1-independent signaling mechanism used by PV, inducing complex instability. This demonstration of ULK1-independent autophagic signaling is novel and leads to a model by which the virus is signaling to generate autophagosomes downstream of ULK1, while at the same time, cleaving cargo receptors, which may affect cargo loading and autophagic degradative flux. Our data suggest that PV has a finely-tuned relationship with the autophagic machinery, generating autophagosomes without using the primary autophagy signaling pathway. ABBREVIATIONS: ACTB - actin beta; ATG13 - autophagy related 13; ATG14 - autophagy related 14; ATG101 - autophagy related 101; BECN1 - beclin 1; CVB3 - coxsackievirus B3; DMV - double-membraned vesicles; EM - electron microscopy; EMCV - encephalomyocarditis virus; EV-71 - enterovirus 71; FMDV - foot and mouth disease virus; GFP - green fluorescent protein; MAP1LC3B/LC3B - microtubule associated protein 1 light chain 3 beta; MOI - multiplicity of infection; MTOR - mechanistic target of rapamycin kinase; PIK3C3 - phosphatidylinositol 3-kinase catalytic subunit type 3; PRKAA2 - protein kinase AMP-activated catalytic subunit alpha 2; PSMG1 - proteasome assembly chaperone 1; PSMG2 - proteasome assembly chaperone 2PV - poliovirus; RB1CC1 - RB1 inducible coiled-coil 1; SQSTM1 - sequestosome 1; ULK1 - unc-51 like autophagy activating kinase 1; ULK2 - unc-51 like autophagy activating kinase 2; WIPI1 - WD repeat domain, phosphoinositide interacting 1.


Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Poliovirus/fisiología , Transducción de Señal , Proteínas Relacionadas con la Autofagia , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Células HEK293 , Células HeLa , Humanos , Poliovirus/ultraestructura , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteína Sequestosoma-1/metabolismo
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