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1.
J Indian Soc Pedod Prev Dent ; 38(3): 315-318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33004732

RESUMO

A 7-month-old female child born to nonconsanguineous parents with a history of global developmental delay, since early infancy had reported to the department with facial features of mild dysmorphism. History of finger sucking and finger biting was evident, as there was a massive scab tissue over the dorsal aspect of the index finger, above the finger nail bed. A huge ulcer was evident on the right side of the dorsal aspect of anterior two-thirds of the tongue. Genetic evaluation through targeted gene sequencing confirmed the diagnosis as hereditary sensory, autonomic neuropathy Type VIII (Online Mendelian Inheritance in Man - 616488). A homozygous missense variation in exon 3 of PRDM12 was detected. A multidisciplinary approach was planned for the management of the child. A soft splint on the maxilla was fabricated and stabilized with an adhesive. However, the final diagnosis was confirmed by a DNA genomic sequencing test, namely a multigene panel testing or comprehensive genomic sequencing.


Assuntos
Neuropatias Hereditárias Sensoriais e Autônomas/diagnóstico , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Neuropatias Hereditárias Sensoriais e Autônomas/terapia , Proteínas de Transporte , Criança , Feminino , Sucção de Dedo , Genômica , Humanos , Lactente , Proteínas do Tecido Nervoso , Língua
2.
Mol Cell ; 80(1): 156-163.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007255

RESUMO

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift toward distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that, in Drosophila, the highly conserved protein ELAV globally regulates all sites of neuronal 3' end processing and directly binds to proximal polyadenylation sites of target mRNAs in vivo. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in an ELAV loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralog FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue ELAV-mediated alternative polyadenylation and alternative splicing. We propose that exon-activated functional rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Éxons/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Masculino , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
3.
Science ; 369(6508): 1166-1167, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32883850
5.
Mol Neurobiol ; 57(12): 5263-5275, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32869183

RESUMO

Similar to its predecessors, coronavirus disease 2019 (COVID-19) exhibits neurotrophic properties, which lead to progression of neurologic sequelae. Besides direct viral invasion to the central nervous system (CNS), indirect CNS involvement through viral-mediated immune response is plausible. Aberrant immune pathways such as extreme release of cytokines (cytokine storm), autoimmunity mediated by cross-reactivity between CNS components and viral particles, and microglial activation propagate CNS damage in these patients. Here, we review the currently available evidence to discuss the plausible immunologic pathways that may contribute to the development of COVID-19 neurological complications, namely Alzheimer's disease, Parkinson's disease, stroke, multiple sclerosis, Guillain-Barre syndrome, seizure, and brainstem involvement.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Doenças do Sistema Nervoso/etiologia , Pandemias , Pneumonia Viral/complicações , Animais , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Tronco Encefálico/fisiopatologia , Tronco Encefálico/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/imunologia , Efeito Citopatogênico Viral , Surtos de Doenças , Síndrome de Guillain-Barré/etiologia , Síndrome de Guillain-Barré/imunologia , Humanos , Camundongos , Esclerose Múltipla/etiologia , Esclerose Múltipla/imunologia , Proteínas do Tecido Nervoso/fisiologia , Doenças do Sistema Nervoso/imunologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/imunologia , Neuroglia/patologia , Neuroglia/virologia , Neurônios/patologia , Neurônios/virologia , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/imunologia , Receptores Virais/fisiologia , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Convulsões/etiologia , Convulsões/imunologia , Síndrome Respiratória Aguda Grave/complicações , Síndrome Respiratória Aguda Grave/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/imunologia
6.
Chem Biol Interact ; 330: 109248, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871113

RESUMO

Dextromethorphan (DM) is a cough suppressant available in many prescribed and over-the-counter medications. Adverse reactions induced by DM have been regularly reported, including allergic skin reactions in some cases. However, the underlying mechanisms of local anaphylaxis induced by DM have not been elucidated. In this study, we found that DM could activate mast cells to increase calcium mobilization and release ß-hexosaminidase, histamine, tumor necrosis factor-α, MCP-1, and IL-8 in a dose-dependent manner. The allergic reactions were confirmed by hind paw swelling and extravasation assay in vivo. Furthermore, DM was revealed to induce local anaphylaxis via MRGPRX2 by the mast cell-deficient kitW-sh/W-sh mice and MRGPRX2 knockdown mast cells. And the MRGPRX2-HEK293/CMC analysis and frontal analysis also showed that DM has a considerable affinity with MRGPRX2. Together, our findings suggest that close monitoring should be drawn on patients with DM for its potential anaphylaxis via MRGPRX2.


Assuntos
Anafilaxia/induzido quimicamente , Dextrometorfano/efeitos adversos , Mastócitos/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Antitussígenos/efeitos adversos , Células Cultivadas , Dextrometorfano/toxicidade , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Receptores de Neuropeptídeos/metabolismo
7.
Chem Biol Interact ; 330: 109251, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32888910

RESUMO

Cisplatin induces acute renal failure in humans and mice.Tubular apoptosis, necrosis and inflammation are the primary pathogenesis of cisplatin-induced acute kidney injury(AKI). We previously reported that the depletion of Numb from proximal tubules exacerbates tubular cells apoptosis in cisplatin-induced AKI, however, the role of Numb in tubular necrosis and renal inflammation in cisplatin-induced AKI remains unclear. A mouse model of AKI was produced by cisplatin intraperitoneally injection in mice from proximal tubule-specific depletion of Numb (PT-Nb-KO) and their wild-type littermates (PT-Nb-WT) respectively. Renal Numb expression was determined by Western blotting. Renal morphological damage was examined by hematoxylin and eosin staining (H&E staining). Tubular necrosis was evaluated by histological study and the protein level of renal Mixed lineage kinase domain-like protein (MLKL) which is a molecular marker of necrosis. Leukocyte infiltration and pro-inflammatory cytokines was determined by immunostaining and quantitative real-time PCR (qRT-PCR) respectively.The protein level of Numb was dramatically decreased in kidneys of PT-Nb-KO mice compared with PT-Nb-WT mice. After cisplatin injection, a significant increase of tubular injury score and the protein level of renal MLKL were detected in PT-Nb-KO mice compared with those in PT-Nb-WT. In addition, the number of F4/80-positve and CD3-positive cells, markers for macrophages and neutraphils respectively, showed significantly increased in kidneys from PT-Nb-KO mice compared with those in PT-Nb-WT mice. Consistently, the gene expression of pro-inflammatory cytokines including TNF-α and MCP-1 in the kidneys was higher in PT-Nb-KO mice than those in PT-Nb-WT mice. Numb play additional protective role in cisplatin-induced AKI through ameliorating tubular necrosis and renal inflammation besides attenuating cisplatin-induced tubular apoptosis.


Assuntos
Lesão Renal Aguda/patologia , Cisplatino/efeitos adversos , Inflamação/prevenção & controle , Proteínas de Membrana/fisiologia , Necrose/prevenção & controle , Proteínas do Tecido Nervoso/fisiologia , Animais , Contagem de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/etiologia , Túbulos Renais Proximais/patologia , Mastócitos , Proteínas de Membrana/deficiência , Camundongos , Camundongos Knockout , Necrose/etiologia , Proteínas do Tecido Nervoso/deficiência , Neutrófilos , Proteínas Quinases/metabolismo
9.
Viruses ; 12(9)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911874

RESUMO

Since the global outbreak of SARS-CoV-2 (COVID-19), infections of diverse human organs along with multiple symptoms continue to be reported. However, the susceptibility of the brain to SARS-CoV-2, and the mechanisms underlying neurological infection are still elusive. Here, we utilized human embryonic stem cell-derived brain organoids and monolayer cortical neurons to investigate infection of brain with pseudotyped SARS-CoV-2 viral particles. Spike-containing SARS-CoV-2 pseudovirus infected neural layers within brain organoids. The expression of ACE2, a host cell receptor for SARS-CoV-2, was sustained during the development of brain organoids, especially in the somas of mature neurons, while remaining rare in neural stem cells. However, pseudotyped SARS-CoV-2 was observed in the axon of neurons, which lack ACE2. Neural infectivity of SARS-CoV-2 pseudovirus did not increase in proportion to viral load, but only 10% of neurons were infected. Our findings demonstrate that brain organoids provide a useful model for investigating SARS-CoV-2 entry into the human brain and elucidating the susceptibility of the brain to SARS-CoV-2.


Assuntos
Betacoronavirus/fisiologia , Neurônios/virologia , Organoides/virologia , Prosencéfalo/virologia , Glicoproteína da Espícula de Coronavírus/fisiologia , Axônios/enzimologia , Diferenciação Celular , Células Cultivadas , Córtex Cerebral/citologia , Células-Tronco Embrionárias/virologia , Células HEK293 , Humanos , Proteínas do Tecido Nervoso/fisiologia , Células-Tronco Neurais/enzimologia , Células-Tronco Neurais/virologia , Neurônios/enzimologia , Peptidil Dipeptidase A/fisiologia , Prosencéfalo/citologia , Receptores Virais/fisiologia , Carga Viral , Tropismo Viral , Internalização do Vírus
10.
PLoS Genet ; 16(8): e1009003, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866139

RESUMO

Sensory systems rely on neuromodulators, such as serotonin, to provide flexibility for information processing as stimuli vary, such as light intensity throughout the day. Serotonergic neurons broadly innervate the optic ganglia of Drosophila melanogaster, a widely used model for studying vision. It remains unclear whether serotonin modulates the physiology of interneurons in the optic ganglia. To address this question, we first mapped the expression patterns of serotonin receptors in the visual system, focusing on a subset of cells with processes in the first optic ganglion, the lamina. Serotonin receptor expression was found in several types of columnar cells in the lamina including 5-HT2B in lamina monopolar cell L2, required for spatiotemporal luminance contrast, and both 5-HT1A and 5-HT1B in T1 cells, whose function is unknown. Subcellular mapping with GFP-tagged 5-HT2B and 5-HT1A constructs indicated that these receptors localize to layer M2 of the medulla, proximal to serotonergic boutons, suggesting that the medulla neuropil is the primary site of serotonergic regulation for these neurons. Exogenous serotonin increased basal intracellular calcium in L2 terminals in layer M2 and modestly decreased the duration of visually induced calcium transients in L2 neurons following repeated dark flashes, but otherwise did not alter the calcium transients. Flies without functional 5-HT2B failed to show an increase in basal calcium in response to serotonin. 5-HT2B mutants also failed to show a change in amplitude in their response to repeated light flashes but other calcium transient parameters were relatively unaffected. While we did not detect serotonin receptor expression in L1 neurons, they, like L2, underwent serotonin-induced changes in basal calcium, presumably via interactions with other cells. These data demonstrate that serotonin modulates the physiology of interneurons involved in early visual processing in Drosophila.


Assuntos
Receptor 5-HT1B de Serotonina/genética , Receptores 5-HT1 de Serotonina/genética , Receptores 5-HT2 de Serotonina/genética , Neurônios Serotoninérgicos/metabolismo , Serotonina/metabolismo , Animais , Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica/genética , Interneurônios/metabolismo , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Neurotransmissores/genética , Receptores de Serotonina/genética , Serotonina/genética , Percepção Visual/genética
11.
Nat Commun ; 11(1): 4491, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901033

RESUMO

The functionality of the nervous system requires transmission of information along axons with high speed and precision. Conductance velocity depends on axonal diameter whereas signaling precision requires a block of electrical crosstalk between axons, known as ephaptic coupling. Here, we use the peripheral nervous system of Drosophila larvae to determine how glia regulates axonal properties. We show that wrapping glial differentiation depends on gap junctions and FGF-signaling. Abnormal glial differentiation affects axonal diameter and conductance velocity and causes mild behavioral phenotypes that can be rescued by a sphingosine-rich diet. Ablation of wrapping glia does not further impair axonal diameter and conductance velocity but causes a prominent locomotion phenotype that cannot be rescued by sphingosine. Moreover, optogenetically evoked locomotor patterns do not depend on conductance speed but require the presence of wrapping glial processes. In conclusion, our data indicate that wrapping glia modulates both speed and precision of neuronal signaling.


Assuntos
Drosophila melanogaster/fisiologia , Animais , Animais Geneticamente Modificados , Axônios/fisiologia , Diferenciação Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Larva/citologia , Larva/fisiologia , Locomoção/fisiologia , Modelos Neurológicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Neuroglia/citologia , Neuroglia/fisiologia , Optogenética , Sistema Nervoso Periférico/citologia , Sistema Nervoso Periférico/fisiologia , Fenótipo , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais
12.
Nat Commun ; 11(1): 4112, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807784

RESUMO

Macropinocytosis is essential for myeloid cells to survey their environment and for growth of RAS-transformed cancer cells. Several growth factors and inflammatory stimuli are known to induce macropinocytosis, but its endogenous inhibitors have remained elusive. Stimulation of Roundabout receptors by Slit ligands inhibits directional migration of many cell types, including immune cells and cancer cells. We report that SLIT2 inhibits macropinocytosis in vitro and in vivo by inducing cytoskeletal changes in macrophages. In mice, SLIT2 attenuates the uptake of muramyl dipeptide, thereby preventing NOD2-dependent activation of NF-κB and consequent secretion of pro-inflammatory chemokine, CXCL1. Conversely, blocking the action of endogenous SLIT2 enhances CXCL1 secretion. SLIT2 also inhibits macropinocytosis in RAS-transformed cancer cells, thereby decreasing their survival in nutrient-deficient conditions which resemble tumor microenvironment. Our results identify SLIT2 as a physiological inhibitor of macropinocytosis and challenge the conventional notion that signals that enhance macropinocytosis negatively regulate cell migration, and vice versa.


Assuntos
Citoesqueleto/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Animais , Quimiocina CXCL1/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/genética , Macrófagos/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteínas do Tecido Nervoso/genética , Fagócitos/metabolismo , Pinocitose/genética , Pinocitose/fisiologia , Receptores Imunológicos/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo
13.
PLoS Biol ; 18(8): e3000762, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760088

RESUMO

Centrosomes, the main microtubule organizing centers (MTOCs) of metazoan cells, contain an older "mother" and a younger "daughter" centriole. Stem cells either inherit the mother or daughter-centriole-containing centrosome, providing a possible mechanism for biased delivery of cell fate determinants. However, the mechanisms regulating centrosome asymmetry and biased centrosome segregation are unclear. Using 3D-structured illumination microscopy (3D-SIM) and live-cell imaging, we show in fly neural stem cells (neuroblasts) that the mitotic kinase Polo and its centriolar protein substrate Centrobin (Cnb) accumulate on the daughter centriole during mitosis, thereby generating molecularly distinct mother and daughter centrioles before interphase. Cnb's asymmetric localization, potentially involving a direct relocalization mechanism, is regulated by Polo-mediated phosphorylation, whereas Polo's daughter centriole enrichment requires both Wdr62 and Cnb. Based on optogenetic protein mislocalization experiments, we propose that the establishment of centriole asymmetry in mitosis primes biased interphase MTOC activity, necessary for correct spindle orientation.


Assuntos
Proteínas de Ciclo Celular/genética , Centríolos/metabolismo , Centrossomo/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Mitose , Proteínas Serina-Treonina Quinases/genética , Animais , Animais Geneticamente Modificados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centríolos/ultraestrutura , Centrossomo/ultraestrutura , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Interfase , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Optogenética/métodos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
14.
Science ; 369(6507)2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32855309

RESUMO

Neuronal synapses undergo structural and functional changes throughout life, which are essential for nervous system physiology. However, these changes may also perturb the excitatory-inhibitory neurotransmission balance and trigger neuropsychiatric and neurological disorders. Molecular tools to restore this balance are highly desirable. Here, we designed and characterized CPTX, a synthetic synaptic organizer combining structural elements from cerebellin-1 and neuronal pentraxin-1. CPTX can interact with presynaptic neurexins and postsynaptic AMPA-type ionotropic glutamate receptors and induced the formation of excitatory synapses both in vitro and in vivo. CPTX restored synaptic functions, motor coordination, spatial and contextual memories, and locomotion in mouse models for cerebellar ataxia, Alzheimer's disease, and spinal cord injury, respectively. Thus, CPTX represents a prototype for structure-guided biologics that can efficiently repair or remodel neuronal circuits.


Assuntos
Proteína C-Reativa/farmacologia , Proteínas do Tecido Nervoso/farmacologia , Vias Neurais/efeitos dos fármacos , Precursores de Proteínas/farmacologia , Receptores de AMPA/metabolismo , Proteínas Recombinantes/farmacologia , Sinapses/efeitos dos fármacos , Doença de Alzheimer/terapia , Animais , Proteína C-Reativa/química , Proteína C-Reativa/uso terapêutico , Ataxia Cerebelar/terapia , Modelos Animais de Doenças , Células HEK293 , Hipocampo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/uso terapêutico , Domínios Proteicos , Precursores de Proteínas/química , Precursores de Proteínas/uso terapêutico , Receptores de Glutamato/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/uso terapêutico , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/fisiologia
15.
J Neurovirol ; 26(5): 619-630, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32839951

RESUMO

The recent pandemic outbreak of coronavirus is pathogenic and a highly transmittable viral infection caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2). In this time of ongoing pandemic, many emerging reports suggested that the SARS-CoV-2 has inimical effects on neurological functions, and even causes serious neurological damage. The neurological symptoms associated with COVID-19 include headache, dizziness, depression, anosmia, encephalitis, stroke, epileptic seizures, and Guillain-Barre syndrome along with many others. The involvement of the CNS may be related with poor prognosis and disease worsening. Here, we review the evidence of nervous system involvement and currently known neurological manifestations in COVID-19 infections caused by SARS-CoV-2. We prioritize the 332 human targets of SARS-CoV-2 according to their association with brain-related disease and identified 73 candidate genes. We prioritize these 73 genes according to their spatio-temporal expression in the different regions of brain and also through evolutionary intolerance analysis. The prioritized genes could be considered potential indicators of COVID-19-associated neurological symptoms and thus act as a possible therapeutic target for the prevention and treatment of CNS manifestations associated with COVID-19 patients.


Assuntos
Betacoronavirus/patogenicidade , Encéfalo/metabolismo , Infecções por Coronavirus/genética , Interações Hospedeiro-Patógeno/genética , Proteínas do Tecido Nervoso/genética , Pneumonia Viral/genética , Proteínas Virais/genética , Encéfalo/patologia , Encéfalo/virologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Depressão , Tontura/complicações , Tontura/genética , Tontura/patologia , Tontura/virologia , Encefalite/complicações , Encefalite/genética , Encefalite/patologia , Encefalite/virologia , Síndrome de Guillain-Barré/complicações , Síndrome de Guillain-Barré/genética , Síndrome de Guillain-Barré/patologia , Síndrome de Guillain-Barré/virologia , Cefaleia/complicações , Cefaleia/genética , Cefaleia/patologia , Cefaleia/virologia , Humanos , Proteínas do Tecido Nervoso/classificação , Proteínas do Tecido Nervoso/metabolismo , Transtornos do Olfato/complicações , Transtornos do Olfato/genética , Transtornos do Olfato/patologia , Transtornos do Olfato/virologia , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Mapeamento de Interação de Proteínas , Convulsões/complicações , Convulsões/genética , Convulsões/patologia , Convulsões/virologia , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/virologia , Proteínas Virais/metabolismo
16.
Mol Cell ; 79(5): 768-781.e7, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32738194

RESUMO

Misfolded proteins in the endoplasmic reticulum (ER) are degraded by ER-associated degradation (ERAD). Although ERAD components involved in degradation of luminal substrates are well characterized, much less is known about quality control of membrane proteins. Here, we analyzed the degradation pathways of two short-lived ER membrane model proteins in mammalian cells. Using a CRISPR-Cas9 genome-wide library screen, we identified an ERAD branch required for quality control of a subset of membrane proteins. Using biochemical and mass spectrometry approaches, we showed that this ERAD branch is defined by an ER membrane complex consisting of the ubiquitin ligase RNF185, the ubiquitin-like domain containing proteins TMUB1/2 and TMEM259/Membralin, a poorly characterized protein. This complex cooperates with cytosolic ubiquitin ligase UBE3C and p97 ATPase in degrading their membrane substrates. Our data reveal that ERAD branches have remarkable specificity for their membrane substrates, suggesting that multiple, perhaps combinatorial, determinants are involved in substrate selection.


Assuntos
Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Células HEK293 , Células HeLa , Humanos , Domínios Proteicos , Dobramento de Proteína , Proteólise , Proteínas de Saccharomyces cerevisiae/metabolismo , Esterol 14-Desmetilase/metabolismo
17.
Proc Natl Acad Sci U S A ; 117(33): 20265-20273, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747555

RESUMO

Huntington disease (HD) is an ideal model for investigating selective neurodegeneration, as expanded polyQ repeats in the ubiquitously expressed huntingtin (HTT) cause the preferential neurodegeneration in the striatum of the HD patient brains. Here we report that adeno-associated virus (AAV) transduction-mediated depletion of Hap1, the first identified huntingtin-associated protein, in adult HD knock-in (KI) mouse brains leads to selective neuronal loss in the striatum. Further, Hap1 depletion-mediated neuronal loss via AAV transduction requires the presence of mutant HTT. Rhes, a GTPase that is enriched in the striatum and sumoylates mutant HTT to mediate neurotoxicity, binds more N-terminal HTT when Hap1 is deficient. Consistently, more soluble and sumoylated N-terminal HTT is presented in HD KI mouse striatum when HAP1 is absent. Our findings suggest that both Rhes and Hap1 as well as cellular stress contribute to the preferential neurodegeneration in HD, highlighting the involvement of multiple factors in selective neurodegeneration.


Assuntos
Corpo Estriado/patologia , Doença de Huntington/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/fisiologia , Optogenética , Animais , Corpo Estriado/metabolismo , Dependovirus , Regulação da Expressão Gênica , Doença de Huntington/genética , Lasers , Luz , Camundongos , Rede Nervosa , Proteínas do Tecido Nervoso/genética
18.
Am J Hum Genet ; 107(3): 555-563, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32758449

RESUMO

Helsmoortel-Van der Aa syndrome (HVDAS) is a neurodevelopmental condition associated with intellectual disability/developmental delay, autism spectrum disorder, and multiple medical comorbidities. HVDAS is caused by mutations in activity-dependent neuroprotective protein (ADNP). A recent study identified genome-wide DNA methylation changes in 22 individuals with HVDAS, adding to the group of neurodevelopmental disorders with an epigenetic signature. This methylation signature segregated those with HVDAS into two groups based on the location of the mutations. Here, we conducted an independent study on 24 individuals with HVDAS and replicated the existence of the two mutation-dependent episignatures. To probe whether the two distinct episignatures correlate with clinical outcomes, we used deep behavioral and neurobiological data from two prospective cohorts of individuals with a genetic diagnosis of HVDAS. We found limited phenotypic differences between the two HVDAS-affected groups and no evidence that individuals with more widespread methylation changes are more severely affected. Moreover, in spite of the methylation changes, we observed no profound alterations in the blood transcriptome of individuals with HVDAS. Our data warrant caution in harnessing methylation signatures in HVDAS as a tool for clinical stratification, at least with regard to behavioral phenotypes.


Assuntos
Transtorno do Espectro Autista/genética , Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Proteínas do Tecido Nervoso/genética , Transtornos do Neurodesenvolvimento/genética , Transtorno do Espectro Autista/patologia , Criança , Metilação de DNA/genética , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Epigênese Genética/genética , Feminino , Humanos , Deficiência Intelectual/patologia , Masculino , Mutação/genética , Transtornos do Neurodesenvolvimento/patologia , Fenótipo , Transcriptoma/genética
19.
PLoS Genet ; 16(8): e1008955, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776921

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder characterized by excess lipid accumulation in the liver without significant consumption of alcohol. The transmembrane 6 superfamily member 2 (TM6SF2) E167K missense variant strongly associates with NAFLD in humans. The E167K mutation destabilizes TM6SF2, resulting in hepatic lipid accumulation and low serum lipid levels. However, the molecular mechanism by which TM6SF2 regulates lipid metabolism remains unclear. By using tandem affinity purification in combination with mass spectrometry, we found that apolipoprotein B (APOB), ER lipid raft protein (ERLIN) 1 and 2 were TM6SF2-interacting proteins. ERLINs and TM6SF2 mutually bound and stabilized each other. TM6SF2 bound and stabilized APOB via two luminal loops. ERLINs did not interact with APOB directly but still increased APOB stability through stabilizing TM6SF2. This APOB stabilization was hampered by the E167K mutation that reduced the protein expression of TM6SF2. In mice, knockout of Tm6sf2 and knockdown of Tm6sf2 or Erlins decreased hepatic APOB protein level, causing lipid accumulation in the liver and lowering lipid levels in the serum. We conclude that defective APOB stabilization, as a result of ERLINs or TM6SF2 deficiency or E167K mutation, is a key factor contributing to NAFLD.


Assuntos
Apolipoproteína B-100/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Hepatopatia Gordurosa não Alcoólica/genética , Animais , Colesterol/genética , Colesterol/metabolismo , Predisposição Genética para Doença , Genótipo , Humanos , Imunoprecipitação , Metabolismo dos Lipídeos/genética , Lipídeos/sangue , Lipídeos/genética , Camundongos , Camundongos Knockout , Complexos Multiproteicos/genética , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica/genética , Transfecção
20.
Nat Commun ; 11(1): 3946, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770055

RESUMO

Melanomas can switch to a dedifferentiated cell state upon exposure to cytotoxic T cells. However, it is unclear whether such tumor cells pre-exist in patients and whether they can be resensitized to immunotherapy. Here, we chronically expose (patient-derived) melanoma cell lines to differentiation antigen-specific cytotoxic T cells and observe strong enrichment of a pre-existing NGFRhi population. These fractions are refractory also to T cells recognizing non-differentiation antigens, as well as to BRAF + MEK inhibitors. NGFRhi cells induce the neurotrophic factor BDNF, which contributes to T cell resistance, as does NGFR. In melanoma patients, a tumor-intrinsic NGFR signature predicts anti-PD-1 therapy resistance, and NGFRhi tumor fractions are associated with immune exclusion. Lastly, pharmacologic NGFR inhibition restores tumor sensitivity to T cell attack in vitro and in melanoma xenografts. These findings demonstrate the existence of a stable and pre-existing NGFRhi multitherapy-refractory melanoma subpopulation, which ought to be eliminated to revert intrinsic resistance to immunotherapeutic intervention.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Melanoma/tratamento farmacológico , Proteínas do Tecido Nervoso/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fator de Crescimento Neural/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Linfócitos T Citotóxicos/imunologia , Animais , Antineoplásicos Imunológicos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Masculino , Melanoma/genética , Melanoma/imunologia , Melanoma/patologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , RNA-Seq , Receptores de Fator de Crescimento Neural/antagonistas & inibidores , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/metabolismo , Evasão Tumoral/genética , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
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