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1.
Cell ; 186(18): 3968-3982.e15, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37586362

RESUMO

Ductal carcinoma in situ (DCIS) is a common precursor of invasive breast cancer. Our understanding of its genomic progression to recurrent disease remains poor, partly due to challenges associated with the genomic profiling of formalin-fixed paraffin-embedded (FFPE) materials. Here, we developed Arc-well, a high-throughput single-cell DNA-sequencing method that is compatible with FFPE materials. We validated our method by profiling 40,330 single cells from cell lines, a frozen tissue, and 27 FFPE samples from breast, lung, and prostate tumors stored for 3-31 years. Analysis of 10 patients with matched DCIS and cancers that recurred 2-16 years later show that many primary DCIS had already undergone whole-genome doubling and clonal diversification and that they shared genomic lineages with persistent subclones in the recurrences. Evolutionary analysis suggests that most DCIS cases in our cohort underwent an evolutionary bottleneck, and further identified chromosome aberrations in the persistent subclones that were associated with recurrence.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Feminino , Humanos , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Progressão da Doença , Genômica/métodos , Análise da Expressão Gênica de Célula Única , Linhagem Celular Tumoral
2.
Cell ; 172(1-2): 275-288.e18, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29328916

RESUMO

The neuronal gene Arc is essential for long-lasting information storage in the mammalian brain, mediates various forms of synaptic plasticity, and has been implicated in neurodevelopmental disorders. However, little is known about Arc's molecular function and evolutionary origins. Here, we show that Arc self-assembles into virus-like capsids that encapsulate RNA. Endogenous Arc protein is released from neurons in extracellular vesicles that mediate the transfer of Arc mRNA into new target cells, where it can undergo activity-dependent translation. Purified Arc capsids are endocytosed and are able to transfer Arc mRNA into the cytoplasm of neurons. These results show that Arc exhibits similar molecular properties to retroviral Gag proteins. Evolutionary analysis indicates that Arc is derived from a vertebrate lineage of Ty3/gypsy retrotransposons, which are also ancestors to retroviruses. These findings suggest that Gag retroelements have been repurposed during evolution to mediate intercellular communication in the nervous system.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Exossomos/metabolismo , Produtos do Gene gag/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Animais , Células Cultivadas , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Endocitose , Feminino , Produtos do Gene gag/química , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Neurônios/fisiologia
3.
Cell ; 172(1-2): 262-274.e11, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29328915

RESUMO

Arc/Arg3.1 is required for synaptic plasticity and cognition, and mutations in this gene are linked to autism and schizophrenia. Arc bears a domain resembling retroviral/retrotransposon Gag-like proteins, which multimerize into a capsid that packages viral RNA. The significance of such a domain in a plasticity molecule is uncertain. Here, we report that the Drosophila Arc1 protein forms capsid-like structures that bind darc1 mRNA in neurons and is loaded into extracellular vesicles that are transferred from motorneurons to muscles. This loading and transfer depends on the darc1-mRNA 3' untranslated region, which contains retrotransposon-like sequences. Disrupting transfer blocks synaptic plasticity, suggesting that transfer of dArc1 complexed with its mRNA is required for this function. Notably, cultured cells also release extracellular vesicles containing the Gag region of the Copia retrotransposon complexed with its own mRNA. Taken together, our results point to a trans-synaptic mRNA transport mechanism involving retrovirus-like capsids and extracellular vesicles.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Produtos do Gene gag/genética , Corpos Multivesiculares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Terminações Pré-Sinápticas/metabolismo , RNA Mensageiro/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Produtos do Gene gag/química , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Junção Neuromuscular/metabolismo , Plasticidade Neuronal , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Terminações Pré-Sinápticas/fisiologia , Ligação Proteica , Domínios Proteicos , Retroelementos/genética
4.
Mol Cell ; 75(1): 13-25.e5, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31151856

RESUMO

Arc is a synaptic protein essential for memory consolidation. Recent studies indicate that Arc originates in evolution from a Ty3-Gypsy retrotransposon GAG domain. The N-lobe of Arc GAG domain acquired a hydrophobic binding pocket in higher vertebrates that is essential for Arc's canonical function to weaken excitatory synapses. Here, we report that Arc GAG also acquired phosphorylation sites that can acutely regulate its synaptic function. CaMKII phosphorylates the N-lobe of the Arc GAG domain and disrupts an interaction surface essential for high-order oligomerization. In Purkinje neurons, CaMKII phosphorylation acutely reverses Arc's synaptic action. Mutant Arc that cannot be phosphorylated by CaMKII enhances metabotropic receptor-dependent depression in the hippocampus but does not alter baseline synaptic transmission or long-term potentiation. Behavioral studies indicate that hippocampus- and amygdala-dependent learning requires Arc GAG domain phosphorylation. These studies provide an atomic model for dynamic and local control of Arc function underlying synaptic plasticity and memory.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Células de Purkinje/metabolismo , Sequência de Aminoácidos , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/metabolismo , Animais , Sítios de Ligação , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Técnicas de Introdução de Genes , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Fosforilação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Células de Purkinje/citologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sinapses/fisiologia , Transmissão Sináptica
5.
Proc Natl Acad Sci U S A ; 121(13): e2313488121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38513104

RESUMO

Weyl semimetal showing open-arc surface states is a prominent example of topological quantum matter in three dimensions. With the bulk-boundary correspondence present, nontrivial surface-bulk hybridization is inevitable but less understood. Spectroscopies have been often limited to verifying the existence of surface Fermi arcs, whereas its spectral shape related to the hybridization profile in energy-momentum space is not well studied. We present an exactly solvable formalism at the surface for a wide range of prototypical Weyl semimetals. The resonant surface state and the bulk influence coexist as a surface-bulk hybrid and are treated in a unified manner. Directly accessible to angle-resolved photoemission spectroscopy, we analytically reveal universal information about the system obtained from the spectroscopy of resonant topological states. We systematically find inhomogeneous and anisotropic singular responses around the surface-bulk merging borderline crossing Weyl points, highlighting its critical role in the Weyl topology. The response in scanning tunneling spectroscopy is also discussed. The results will provide much-needed insight into the surface-bulk-coupled physical properties and guide in-depth spectroscopic investigation of the nontrivial hybrid in many topological semimetal materials.

6.
Traffic ; 24(11): 522-532, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37545033

RESUMO

Localization of messenger RNA (mRNA) in dendrites is crucial for regulating gene expression during long-term memory formation. mRNA binds to RNA-binding proteins (RBPs) to form messenger ribonucleoprotein (mRNP) complexes that are transported by motor proteins along microtubules to their target synapses. However, the dynamics by which mRNPs find their target locations in the dendrite have not been well understood. Here, we investigated the motion of endogenous ß-actin and Arc mRNPs in dissociated mouse hippocampal neurons using the MS2 and PP7 stem-loop systems, respectively. By evaluating the statistical properties of mRNP movement, we found that the aging Lévy walk model effectively describes both ß-actin and Arc mRNP transport in proximal dendrites. A critical difference between ß-actin and Arc mRNPs was the aging time, the time lag between transport initiation and measurement initiation. The longer mean aging time of ß-actin mRNP (~100 s) compared with that of Arc mRNP (~30 s) reflects the longer half-life of constitutively expressed ß-actin mRNP. Furthermore, our model also permitted us to estimate the ratio of newly generated and pre-existing ß-actin mRNPs in the dendrites. This study offers a robust theoretical framework for mRNP transport, which provides insight into how mRNPs locate their targets in neurons.


Assuntos
Actinas , Ribonucleoproteínas , Camundongos , Animais , Actinas/metabolismo , Ribonucleoproteínas/metabolismo , Dendritos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
7.
J Biol Chem ; 300(5): 107237, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552740

RESUMO

Tauopathies are neurodegenerative disorders characterized by the deposition of aggregates of the microtubule-associated protein tau, a main component of neurofibrillary tangles. Alzheimer's disease (AD) is the most common type of tauopathy and dementia, with amyloid-beta pathology as an additional hallmark feature of the disease. Besides its role in stabilizing microtubules, tau is localized at postsynaptic sites and can regulate synaptic plasticity. The activity-regulated cytoskeleton-associated protein (Arc) is an immediate early gene that plays a key role in synaptic plasticity, learning, and memory. Arc has been implicated in AD pathogenesis and regulates the release of amyloid-beta. We found that decreased Arc levels correlate with AD status and disease severity. Importantly, Arc protein was upregulated in the hippocampus of Tau KO mice and dendrites of Tau KO primary hippocampal neurons. Overexpression of tau decreased Arc stability in an activity-dependent manner, exclusively in neuronal dendrites, which was coupled to an increase in the expression of dendritic and somatic surface GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors. The tau-dependent decrease in Arc was found to be proteasome-sensitive, yet independent of Arc ubiquitination and required the endophilin-binding domain of Arc. Importantly, these effects on Arc stability and GluA1 localization were not observed in the commonly studied tau mutant, P301L. These observations provide a potential molecular basis for synaptic dysfunction mediated through the accumulation of tau in dendrites. Our findings confirm that Arc is misregulated in AD and further show a physiological role for tau in regulating Arc stability and AMPA receptor targeting.


Assuntos
Proteínas do Citoesqueleto , Dendritos , Proteínas do Tecido Nervoso , Complexo de Endopeptidases do Proteassoma , Proteínas tau , Animais , Humanos , Camundongos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/genética , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/genética , Dendritos/metabolismo , Dendritos/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Neurônios/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica , Proteínas tau/metabolismo , Proteínas tau/genética , Ubiquitina/metabolismo , Ubiquitinação
8.
Immunity ; 45(2): 267-79, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27496733

RESUMO

Toll-like receptors (TLRs) and other pattern-recognition receptors (PRRs) sense microbial ligands and initiate signaling to induce inflammatory responses. Although the quality of inflammatory responses is influenced by internalization of TLRs, the role of endosomal maturation in clearing receptors and terminating inflammatory responses is not well understood. Here, we report that Drosophila and mammalian Vps33B proteins play critical roles in the maturation of phagosomes and endosomes following microbial recognition. Vps33B was necessary for clearance of endosomes containing internalized PRRs, failure of which resulted in enhanced signaling and expression of inflammatory mediators. Lack of Vps33B had no effect on trafficking of endosomes containing non-microbial cargo. These findings indicate that Vps33B function is critical for determining the fate of signaling endosomes formed following PRR activation. Exaggerated inflammatory responses dictated by persistence of receptors in aberrant endosomal compartments could therefore contribute to symptoms of ARC syndrome, a disease linked to loss of Vps33B.


Assuntos
Artrogripose/imunologia , Colestase/imunologia , Proteínas de Drosophila/metabolismo , Endossomos/metabolismo , Infecções por Escherichia coli/imunologia , Inflamação/imunologia , Macrófagos/fisiologia , Insuficiência Renal/imunologia , Proteínas de Transporte Vesicular/metabolismo , Animais , Animais Geneticamente Modificados , Artrogripose/genética , Células Cultivadas , Colestase/genética , Drosophila , Proteínas de Drosophila/genética , Técnicas de Inativação de Genes , Camundongos , Transporte Proteico , RNA Interferente Pequeno/genética , Insuficiência Renal/genética , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Proteínas de Transporte Vesicular/genética
9.
Mol Ther ; 32(6): 1835-1848, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38659225

RESUMO

While conventional chimeric antigen-receptor (CAR)-T therapies have shown remarkable clinical activity in some settings, they can induce severe toxicities and are rarely curative. To address these challenges, we developed a controllable cell therapy where synthetic D-domain-containing proteins (soluble protein antigen-receptor X-linker [SparX]) bind one or more tumor antigens and mark those cells for elimination by genetically modified T cells (antigen-receptor complex [ARC]-T). The chimeric antigen receptor was engineered with a D-domain that specifically binds to the SparX protein via a unique TAG, derived from human alpha-fetoprotein. The interaction is mediated through an epitope on the TAG that is occluded in the native alpha-fetoprotein molecule. In vitro and in vivo data demonstrate that the activation and cytolytic activity of ARC-T cells is dependent on the dose of SparX protein and only occurs when ARC-T cells are engaged with SparX proteins bound to antigen-positive cells. ARC-T cell specificity was also redirected in vivo by changing SparX proteins that recognized different tumor antigens to combat inherent or acquired tumor heterogeneity. The ARC-SparX platform is designed to expand patient and physician access to cell therapy by controlling potential toxicities through SparX dosing regimens and enhancing tumor elimination through sequential or simultaneous administration of SparX proteins engineered to bind different tumor antigens.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Linfócitos T , Humanos , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/genética , Animais , Camundongos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Imunoterapia Adotiva/métodos , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias/metabolismo , Ligação Proteica
10.
Mol Ther ; 32(7): 2113-2129, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38788710

RESUMO

Sepsis-associated encephalopathy (SAE) is a frequent complication of severe systemic infection resulting in delirium, premature death, and long-term cognitive impairment. We closely mimicked SAE in a murine peritoneal contamination and infection (PCI) model. We found long-lasting synaptic pathology in the hippocampus including defective long-term synaptic plasticity, reduction of mature neuronal dendritic spines, and severely affected excitatory neurotransmission. Genes related to synaptic signaling, including the gene for activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) and members of the transcription-regulatory EGR gene family, were downregulated. At the protein level, ARC expression and mitogen-activated protein kinase signaling in the brain were affected. For targeted rescue we used adeno-associated virus-mediated overexpression of ARC in the hippocampus in vivo. This recovered defective synaptic plasticity and improved memory dysfunction. Using the enriched environment paradigm as a non-invasive rescue intervention, we found improvement of defective long-term potentiation, memory, and anxiety. The beneficial effects of an enriched environment were accompanied by an increase in brain-derived neurotrophic factor (BDNF) and ARC expression in the hippocampus, suggesting that activation of the BDNF-TrkB pathway leads to restoration of the PCI-induced reduction of ARC. Collectively, our findings identify synaptic pathomechanisms underlying SAE and provide a conceptual approach to target SAE-induced synaptic dysfunction with potential therapeutic applications to patients with SAE.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Disfunção Cognitiva , Proteínas do Citoesqueleto , Modelos Animais de Doenças , Hipocampo , Plasticidade Neuronal , Encefalopatia Associada a Sepse , Animais , Camundongos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/terapia , Disfunção Cognitiva/genética , Encefalopatia Associada a Sepse/metabolismo , Encefalopatia Associada a Sepse/etiologia , Encefalopatia Associada a Sepse/terapia , Encefalopatia Associada a Sepse/genética , Hipocampo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Dependovirus/genética , Masculino , Potenciação de Longa Duração , Receptor trkB/metabolismo , Receptor trkB/genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Sinapses/metabolismo
11.
Bioessays ; 45(3): e2200221, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36650950

RESUMO

The pore-forming BCL-2 family proteins are effectors of mitochondrial poration in apoptosis initiation. Two atypical effectors-BOK and truncated BID (tBID)-join the canonical effectors BAK and BAX. Gene knockout revealed developmental phenotypes in the absence the effectors, supporting their roles in vivo. During apoptosis effectors are activated and change shape from dormant monomers to dynamic oligomers that associate with and permeabilize mitochondria. BID is activated by proteolysis, BOK accumulates on inhibition of its degradation by the E3 ligase gp78, while BAK and BAX undergo direct activation by BH3-only initiators, autoactivation, and crossactivation. Except tBID, effector oligomers on the mitochondria appear as arcs and rings in super-resolution microscopy images. The BH3-in-groove dimers of BAK and BAX, the tBID monomers, and uncharacterized BOK species are the putative building blocks of apoptotic pores. Effectors interact with lipids and bilayers but the mechanism of membrane poration remains elusive. I discuss effector-mediated mitochondrial poration.


Assuntos
Apoptose , Mitocôndrias , Proteína X Associada a bcl-2/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Mitocôndrias/metabolismo , Apoptose/fisiologia
12.
Proc Natl Acad Sci U S A ; 119(27): e2117076119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35776545

RESUMO

Memories are thought to be encoded in populations of neurons called memory trace or engram cells. However, little is known about the dynamics of these cells because of the difficulty in real-time monitoring of them over long periods of time in vivo. To overcome this limitation, we present a genetically encoded RNA indicator (GERI) mouse for intravital chronic imaging of endogenous Arc messenger RNA (mRNA)-a popular marker for memory trace cells. We used our GERI to identify Arc-positive neurons in real time without the delay associated with reporter protein expression in conventional approaches. We found that the Arc-positive neuronal populations rapidly turned over within 2 d in the hippocampal CA1 region, whereas ∼4% of neurons in the retrosplenial cortex consistently expressed Arc following contextual fear conditioning and repeated memory retrievals. Dual imaging of GERI and a calcium indicator in CA1 of mice navigating a virtual reality environment revealed that only the population of neurons expressing Arc during both encoding and retrieval exhibited relatively high calcium activity in a context-specific manner. This in vivo RNA-imaging approach opens the possibility of unraveling the dynamics of the neuronal population underlying various learning and memory processes.


Assuntos
Região CA1 Hipocampal , Proteínas do Citoesqueleto , Memória , Proteínas do Tecido Nervoso , RNA Mensageiro , Animais , Região CA1 Hipocampal/metabolismo , Cálcio/metabolismo , Condicionamento Clássico , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/genética , Medo , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
13.
Nano Lett ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023921

RESUMO

The doping of perovskites with mixed cations and mixed halides is an effective strategy to optimize phase stability. In this study, we introduce a cubic black phase perovskite CsyFA(1-y)Pb(BrxI(1-x))3 artificial synapse, using phase engineering by adjusting the cesium-bromide content. Low-bromine mixed perovskites are suitable to improve the electric pulse excitation sensitivity and stability of the device. Specifically, the low-bromine and low-cesium mixed perovskite (x = 0.15, y = 0.22) annealed at 373 K allows the device to maintain logic response even after 1000 mechanical flex/flat cycles. The device also shows good thermal stability up to temperatures of 333 K. We have demonstrated reflex-arc behavior with MCMHP synaptic units, capable of making sensory warnings at high frequency. This compositionally engineered, dual-mixed perovskite synaptic device provides significant potential for perceptual soft neurorobotic systems and prostheses.

14.
J Neurosci ; 43(7): 1178-1190, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36623874

RESUMO

The accessory olfactory system (AOS) is critical for the development and expression of social behavior. The first dedicated circuit in the AOS, the accessory olfactory bulb (AOB), exhibits cellular and network plasticity in male and female mice after social experience. In the AOB, interneurons called internal granule cells (IGCs) express the plasticity-associated immediate-early gene Arc following intermale aggression or mating. Here, we sought to better understand how Arc-expressing IGCs shape AOB information processing and social behavior in the context of territorial aggression. We used "ArcTRAP" (Arc-CreERT2) transgenic mice to selectively and permanently label Arc-expressing IGCs following male-male resident-intruder interactions. Using whole-cell patch-clamp electrophysiology, we found that Arc-expressing IGCs display increased intrinsic excitability for several days after a single resident-intruder interaction. Further, we found that Arc-expressing IGCs maintain this increased excitability across repeated resident-intruder interactions, during which resident mice increase or "ramp" their aggression. We tested the hypothesis that Arc-expressing IGCs participate in ramping aggression. Using a combination of ArcTRAP mice and chemogenetics (Cre-dependent hM4D(Gi)-mCherry AAV injections), we found that disruption of Arc-expressing IGC activity during repeated resident-intruder interactions abolishes the ramping aggression exhibited by resident male mice. This work shows that Arc-expressing AOB IGC ensembles are activated by specific chemosensory environments, and play an integral role in the establishment and expression of sex-typical social behavior. These studies identify a population of plastic interneurons in an early chemosensory circuit that display physiological features consistent with simple memory formation, increasing our understanding of central chemosensory processing and mammalian social behavior.SIGNIFICANCE STATEMENT The accessory olfactory system plays a vital role in rodent chemosensory social behavior. We studied experience-dependent plasticity in the accessory olfactory bulb and found that internal granule cells expressing the immediate-early gene Arc after the resident-intruder paradigm increase their excitability for several days. We investigated the roles of these Arc-expressing internal granule cells on chemosensory social behavior by chemogenetically manipulating their excitability during repeated social interactions. We found that inhibiting these cells eliminated intermale aggressive ramping behavior. These studies identify a population of plastic interneurons in an early chemosensory circuit that display physiological features consistent with simple memory formation, increasing our understanding of central chemosensory processing and mammalian social behavior.


Assuntos
Interneurônios , Bulbo Olfatório , Camundongos , Masculino , Feminino , Animais , Bulbo Olfatório/fisiologia , Interneurônios/fisiologia , Neurônios , Comportamento Social , Agressão , Camundongos Transgênicos , Mamíferos
15.
J Biol Chem ; 299(6): 104718, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37062417

RESUMO

Loss-of-function variants of vacuolar protein sorting proteins VPS33B and VPS16B (VIPAS39) are causative for arthrogryposis, renal dysfunction, and cholestasis syndrome, where early lethality of patients indicates that VPS33B and VPS16B play essential cellular roles. VPS33B is a member of the Sec1-Munc18 protein family and thought to facilitate vesicular fusion via interaction with soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes, like its paralog VPS33A in the homotypic fusion and vacuole sorting complex. VPS33B and VPS16B are known to associate, but little is known about the composition, structure, or function of the VPS33B-VPS16B complex. We show here that human VPS33B-VPS16B is a high molecular weight complex, which we expressed in yeast to perform structural, composition, and stability analysis. Circular dichroism data indicate VPS33B-VPS16B has a well-folded α-helical secondary structure, and size-exclusion chromatography-multiangle light scattering revealed a molecular weight of ∼315 kDa. Quantitative immunoblotting indicated a VPS33B:VPS16B ratio of 2:3. Expression of arthrogryposis, renal dysfunction, and cholestasis syndrome-causing VPS33B missense variants showed L30P disrupts complex formation but not S243F or H344D. Truncated VPS16B (amino acids 143 to 316) was sufficient to form a complex with VPS33B. Small-angle X-ray scattering and negative-staining EM revealed a two-lobed shape for VPS33B-VPS16B. Avidin tagging indicated that each lobe contains a VPS33B molecule, and they are oriented in opposite directions. We propose a structure for VPS33B-VPS16B that allows the VPS33B at each end to interact with separate SNARE bundles and/or SNAREpins, plus associated membrane components. These observations reveal the only known potentially bidirectional Sec1-Munc18 protein complex.


Assuntos
Proteínas Munc18 , Insuficiência Renal , Humanos , Proteínas SNARE/genética , Síndrome , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
16.
Plant J ; 114(2): 246-261, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36738111

RESUMO

Like other organisms, brown algae are subject to diseases caused by bacteria, fungi, and viruses. Brown algal immunity mechanisms are not well characterized; however, there is evidence suggesting that pathogen receptors exist in brown algae. One key protein family likely associated with brown algal innate immunity possesses an NB-ARC domain analogous to innate immune proteins in plants and animals. In this study, we conducted an extensive survey of NB-ARC genes in brown algae and obtained insights into the domain organization and evolutionary history of the encoded proteins. Our data show that brown algae possess an ancient NB-ARC-tetratricopeptide repeat (NB-TPR) domain architecture. We identified an N-terminal effector domain, the four-helix bundle, which was not previously found associated with NB-ARC domains. The phylogenetic tree including NB-ARC domains from all kingdoms of life suggests the three clades of brown algal NB-TPRs are likely monophyletic, whereas their TPRs seem to have distinct origins. One group of TPRs exhibit intense exon shuffling, with various alternative splicing and diversifying selection acting on them, suggesting exon shuffling is an important mechanism for evolving ligand-binding specificities. The reconciliation of gene duplication and loss events of the NB-ARC genes reveals that more independent gene gains than losses have occurred during brown algal evolution, and that tandem duplication has played a major role in the expansion of NB-ARC genes. Our results substantially enhance our understanding of the evolutionary history and exon shuffling mechanisms of the candidate innate immune repertoire of brown algae.


Assuntos
Processamento Alternativo , Phaeophyceae , Animais , Filogenia , Processamento Alternativo/genética , Proteínas/genética , Éxons , Phaeophyceae/genética , Evolução Molecular
17.
Plant J ; 116(4): 974-988, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37818860

RESUMO

In modern reproducible, hypothesis-driven plant research, scientists are increasingly relying on research data management (RDM) services and infrastructures to streamline the processes of collecting, processing, sharing, and archiving research data. FAIR (i.e., findable, accessible, interoperable, and reusable) research data play a pivotal role in enabling the integration of interdisciplinary knowledge and facilitating the comparison and synthesis of a wide range of analytical findings. The PLANTdataHUB offers a solution that realizes RDM of scientific (meta)data as evolving collections of files in a directory - yielding FAIR digital objects called ARCs - with tools that enable scientists to plan, communicate, collaborate, publish, and reuse data on the same platform while gaining continuous quality control insights. The centralized platform is scalable from personal use to global communities and provides advanced federation capabilities for institutions that prefer to host their own satellite instances. This approach borrows many concepts from software development and adapts them to fit the challenges of the field of modern plant science undergoing digital transformation. The PLANTdataHUB supports researchers in each stage of a scientific project with adaptable continuous quality control insights, from the early planning phase to data publication. The central live instance of PLANTdataHUB is accessible at (https://git.nfdi4plants.org), and it will continue to evolve as a community-driven and dynamic resource that serves the needs of contemporary plant science.


Assuntos
Bases de Dados como Assunto , Disseminação de Informação , Plantas
18.
Neurobiol Dis ; 193: 106457, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423191

RESUMO

Epilepsy is a brain disorder affecting up to 1 in 26 individuals. Despite its clinical importance, the molecular mechanisms of epileptogenesis are still far from clarified. Our previous study showed that disruption of Clock in excitatory neurons alters cortical circuits and leads to generation of focal epilepsy. In this study, a GAD-Cre;Clockflox/flox mouse line with conditional Clock gene knockout in inhibitory neurons was established. We observed that seizure latency was prolonged, the severity and mortality of pilocarpine-induced seizure were significantly reduced, and memory was improved in GAD-Cre;Clockflox/flox mice. We hypothesize that mice with CLOCK knockout in inhibitory neurons have increased threshold for seizure, opposite from mice with CLOCK knockout in excitatory neurons. Further investigation showed Clock knockout in inhibitory neurons upregulated the basal protein level of ARC, a synaptic plasticity-associated immediate-early gene product, likely through the BDNF-ERK pathway. Altered basal levels of ARC may play an important role in epileptogenesis after Clock deletion in inhibitory neurons. Although sEPSCs and intrinsic properties of layer 5 pyramidal neurons in the somatosensory cortex exhibit no changes, the spine density increased in apical dendrite of pyramidal neurons in CLOCK knockout group. Our results suggest an underlying mechanism by which the circadian protein CLOCK in inhibitory neurons participates in neuronal activity and regulates the predisposition to epilepsy.


Assuntos
Epilepsia , Animais , Camundongos , Ansiedade , Suscetibilidade a Doenças/metabolismo , Epilepsia/genética , Epilepsia/metabolismo , Camundongos Knockout , Neurônios/metabolismo , Convulsões/metabolismo
19.
Development ; 148(15)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34323271

RESUMO

Perturbations to animal-associated microbial communities (the microbiota) have deleterious effects on various aspects of host fitness, but the molecular processes underlying these impacts are poorly understood. Here, we identify a connection between the microbiota and the neuronal factor Arc1 that affects growth and metabolism in Drosophila. We find that Arc1 exhibits tissue-specific microbiota-dependent expression changes, and that germ-free flies bearing a null mutation of Arc1 exhibit delayed and stunted larval growth, along with a variety of molecular, cellular and organismal traits indicative of metabolic dysregulation. Remarkably, we show that the majority of these phenotypes can be fully suppressed by mono-association with a single Acetobacter sp. isolate, through mechanisms involving both bacterial diet modification and live bacteria. Additionally, we provide evidence that Arc1 function in key neuroendocrine cells of the larval brain modulates growth and metabolic homeostasis under germ-free conditions. Our results reveal a role for Arc1 in modulating physiological responses to the microbial environment, and highlight how host-microbe interactions can profoundly impact the phenotypic consequences of genetic mutations in an animal host.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Drosophila/metabolismo , Drosophila/fisiologia , Microbiota/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Acetobacter/fisiologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiologia , Homeostase/fisiologia , Larva/metabolismo , Larva/fisiologia , Mutação/fisiologia , Neurônios/metabolismo , Neurônios/fisiologia , Fenótipo
20.
Small ; : e2402752, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822717

RESUMO

Surface modification of Cu current collectors (CCs) is proven to be an effective method for protecting lithium metal anodes. However, few studies have focused on the quality and efficiency of modification layers. Herein, a novel home-made filtered cathode vacuum arc (FCVA) co-deposition system with high modification efficiency, good repeatability and environmental friendliness is proposed to realize the wide range regulation of film composition, structure and performance. Through this system, ZnMgTiAl quaternary alloy films, which have good affinity with Li are successfully constructed on Cu CCs, and the fully enhanced electrochemical performances are achieved. Symmetrical cells constructed with modified CCs maintained a fairly low voltage hysteresis of only 13 mV after 2100 h at a current density of 1 mA cm-2. In addition, the capacity retention rate is as high as 75.0% after 100 cycles in the full cells. The influence of alloy films on the dynamic evolution process of constructing stable artificial solid electrolyte interphase (SEI) layer is revealed by in situ infrared (IR) spectroscopy. This work provides a promising route for designing various feasible modification films for LMBs, and it displays better industrial application prospects than the traditional chemical methods owing to the remarkable controllability and scale-up capacity.

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