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1.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674969

RESUMO

Rett syndrome (RTT) is a severe neurodevelopmental disease caused almost exclusively by mutations to the MeCP2 gene. This disease may be regarded as a synaptopathy, with impairments affecting synaptic plasticity, inhibitory and excitatory transmission and network excitability. The complete understanding of the mechanisms behind how the transcription factor MeCP2 so profoundly affects the mammalian brain are yet to be determined. What is known, is that MeCP2 involvement in activity-dependent expression programs is a critical link between this protein and proper neuronal activity, which allows the correct maturation of connections in the brain. By using RNA-sequencing analysis, we found several immediate-early genes (IEGs, key mediators of activity-dependent responses) directly bound by MeCP2 at the chromatin level and upregulated in the hippocampus and prefrontal cortex of the Mecp2-KO mouse. Quantification of the IEGs response to stimulus both in vivo and in vitro detected an aberrant expression pattern in MeCP2-deficient neurons. Furthermore, altered IEGs levels were found in RTT patient's peripheral blood and brain regions of post-mortem samples, correlating with impaired expression of downstream myelination-related genes. Altogether, these data indicate that proper IEGs expression is crucial for correct synaptic development and that MeCP2 has a key role in the regulation of IEGs.


Assuntos
Síndrome de Rett , Camundongos , Animais , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Genes Precoces , Proteína 2 de Ligação a Metil-CpG/metabolismo , Encéfalo/metabolismo , Neurônios/metabolismo , Hipocampo/metabolismo , Modelos Animais de Doenças , Mamíferos/metabolismo
2.
Nat Commun ; 13(1): 7476, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463234

RESUMO

Growth factor-induced, ERK-mediated induction of immediate-early genes (IEGs) is crucial for cell growth and tumorigenesis. Although IEG expression is mainly regulated at the level of transcription elongation by RNA polymerase-II (Pol-II) promoter-proximal pausing and its release, the role of ERK in this process remains unknown. Here, we identified negative elongation factor (NELF)-A as an ERK substrate. Upon growth factor stimulation, ERK phosphorylates NELF-A, which dissociates NELF from paused Pol-II at the promoter-proximal regions of IEGs, allowing Pol-II to resume elongation and produce full-length transcripts. Furthermore, we found that in cancer cells, PP2A efficiently dephosphorylates NELF-A, thereby preventing aberrant IEG expression induced by ERK-activating oncogenes. However, when PP2A inhibitor proteins are overexpressed, as is frequently observed in cancers, decreased PP2A activity combined with oncogene-mediated ERK activation conspire to induce NELF-A phosphorylation and IEG upregulation, resulting in tumor progression. Our data delineate previously unexplored roles of ERK and PP2A inhibitor proteins in carcinogenesis.


Assuntos
Genes Precoces , RNA Polimerase II , Humanos , RNA Polimerase II/genética , Fosforilação , Fatores de Transcrição , Carcinogênese
3.
J Gen Virol ; 103(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36409610

RESUMO

Human cytomegalovirus is responsible for morbidity and mortality in immune compromised patients and is the leading viral cause of congenital infection. Virus-encoded microRNAs (miRNAs) represent interesting targets for novel antiviral agents. While many cellular targets that augment productive infection have been identified in recent years, regulation of viral genes such as the major viral immediate early protein 72 (IE72) by hcmv-miR-UL112-1 may contribute to both the establishment and the maintenance of latent infection. We employed photoactivated ribonucleotide-enhanced individual nucleotide resolution crosslinking (PAR-iCLIP) to identify murine cytomegalovirus (MCMV) miRNA targets during lytic infection. While the PAR-iCLIP data were of insufficient quality to obtain a comprehensive list of cellular and viral miRNA targets, the most prominent PAR-iCLIP peak in the MCMV genome mapped to the 3' untranslated region of the major viral immediate early 3 (ie3) transcript. We show that this results from two closely positioned binding sites for the abundant MCMV miRNAs miR-M23-2-3p and miR-m01-2-3p. Their pre-expression significantly impaired viral plaque formation. However, mutation of the respective binding sites did not alter viral fitness during acute or subacute infection in vivo. Furthermore, no differences in the induction of virus-specific CD8+ T cells were observed. Future studies will probably need to go beyond studying immunocompetent laboratory mice housed in pathogen-free conditions to reveal the functional relevance of viral miRNA-mediated regulation of key viral immediate early genes.


Assuntos
MicroRNAs , Muromegalovirus , Humanos , Camundongos , Animais , Muromegalovirus/genética , Genes Precoces , Linfócitos T CD8-Positivos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Citomegalovirus/genética , Regiões 3' não Traduzidas
4.
Biochem Biophys Res Commun ; 637: 144-152, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36399800

RESUMO

Cancer cells exhibit increased glutamine consumption compared to normal cells, supporting cell survival and proliferation. Glutamine is converted to α-ketoglutarate (αKG), which then enters the tricarboxylic acid cycle to generate ATP. Recently, therapeutic modulation of glutamine metabolism has become an attractive metabolic anti-cancer strategy. However, how synergistic combination therapy is required to overcome glutamine metabolism drug resistance remains elusive. To address this issue, we first investigated the role of αKG in regulating gene expression in several cancer cell lines. Using RNA-seq analysis and histone modification screening, we demonstrated that αKG reduced the expression of the immediate early gene (IEG) in cancer cells in an H3K27 acetylation-dependent manner. Conversely, glutaminase (GLS) inhibitors induce IEG expression in cancer cells. Furthermore, we showed that siRNA knockdown of orphan nuclear receptor subfamily 4 group A member 1 (NR4A1) induces IEG expression. Notably, the NR4A1 agonist cytosporone B sensitizes GLS inhibitor resistance to cancer cell death. Together, these findings indicate that therapeutic targeting of IEG dysregulation by αKG can be a potentially effective anti-cancer therapeutic strategy for glutamine metabolism inhibitors.


Assuntos
Genes Precoces , Neoplasias , Ácidos Cetoglutáricos , Glutamina , Ciclo do Ácido Cítrico , Terapia Combinada , Neoplasias/tratamento farmacológico , Neoplasias/genética
5.
Hippocampus ; 32(11-12): 839-856, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36314648

RESUMO

Memory is vital to our daily existence. Although a large number of studies have suggested that the hippocampus is dedicated to long-term memory, understanding how memory is anatomically encoded within the hippocampal neuronal network is still lacking. Previously our laboratory showed that hippocampal pyramidal cells are organized in cell clusters to encode both spatial and episodic memory. Based on these findings, we hypothesized that "cluster-type" is a functional organization principal in the hippocampus to encode all types of memory. Here, we tested whether contextual fear, another hippocampus-dependent memory, is also organized in cell clusters. We further investigated the possibility that post-learning sleep may affect functional organization. Cluster formation was examined by assessing the topographic localization of active cells using immediate early gene (IEG, Zif268) imaging methods. The first experiment provides evidence of a cluster-type organization in the hippocampus for fear memory by showing a spatial distribution of adjacent Zif268 positive cells. Exposure to the context itself, without electric shocks, induced a similar cellular formation; however, the degree of clustering was significantly lower. The second experiment provides evidence that sleep plays a role in the refinement and long-term stability of the clusters. The present results confirm the existence of a cluster-type topographic functional neuronal organization in the hippocampus for memory, and further suggest that post-learning sleep enhances the cluster-type organization.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce , Hipocampo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Hipocampo/fisiologia , Medo/fisiologia , Genes Precoces , Sono
6.
Int J Mol Sci ; 23(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36232936

RESUMO

Antipsychotics share the common pharmacological feature of antagonizing the dopamine 2 receptor (D2R), which is abundant in the striatum and involved in both the therapeutic and side effects of this drug's class. The pharmacological blockade of striatal D2R, by disinhibiting the D2R-containing medium-sized spiny neurons (MSNs), leads to a plethora of molecular, cellular and behavioral adaptations, which are central in the action of antipsychotics. Here, we focused on the cell type-specific (D2R-MSNs) regulation of some striatal immediate early genes (IEGs), such as cFos, Arc and Zif268. Taking advantage of transgenic mouse models, pharmacological approaches and immunofluorescence analyses, we found that haloperidol-induced IEGs in the striatum required the synergistic activation of A2a (adenosine) and NMDA (glutamate) receptors. At the intracellular signaling level, we found that the PKA/DARPP-32 and mTOR pathways synergistically cooperate to control the induction of IEGs by haloperidol. By confirming and further expanding previous observations, our results provide novel insights into the regulatory mechanisms underlying the molecular/cellular action of antipsychotics in the striatum.


Assuntos
Antipsicóticos , Haloperidol , Adenosina/metabolismo , Animais , Antipsicóticos/metabolismo , Antipsicóticos/farmacologia , Corpo Estriado/metabolismo , Dopamina/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/genética , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Genes Precoces , Glutamatos/metabolismo , Haloperidol/farmacologia , Camundongos , Camundongos Transgênicos , N-Metilaspartato/metabolismo , Neurônios/metabolismo , Receptores de Dopamina D1/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
7.
Genome Biol ; 23(1): 193, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096941

RESUMO

BACKGROUND: Cytoplasmic polyadenylation element-binding protein 4 (CPEB4) is known to associate with cytoplasmic polyadenylation elements (CPEs) located in the 3' untranslated region (UTR) of specific mRNAs and assemble an activator complex promoting the translation of target mRNAs through cytoplasmic polyadenylation. RESULTS: Here, we find that CPEB4 is part of an alternative repressor complex that mediates mRNA degradation by associating with the evolutionarily conserved CCR4-NOT deadenylase complex. We identify human CPEB4 as an RNA-binding protein (RBP) with enhanced association to poly(A) RNA upon inhibition of class I histone deacetylases (HDACs), a condition known to cause widespread degradation of poly(A)-containing mRNA. Photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) analysis using endogenously tagged CPEB4 in HeLa cells reveals that CPEB4 preferentially binds to the 3'UTR of immediate early gene mRNAs, at G-containing variants of the canonical U- and A-rich CPE located in close proximity to poly(A) sites. By transcriptome-wide mRNA decay measurements, we find that the strength of CPEB4 binding correlates with short mRNA half-lives and that loss of CPEB4 expression leads to the stabilization of immediate early gene mRNAs. Akin to CPEB4, we demonstrate that CPEB1 and CPEB2 also confer mRNA instability by recruitment of the CCR4-NOT complex. CONCLUSIONS: While CPEB4 was previously known for its ability to stimulate cytoplasmic polyadenylation, our findings establish an additional function for CPEB4 as the RNA adaptor of a repressor complex that enhances the degradation of short-lived immediate early gene mRNAs.


Assuntos
Genes Precoces , Estabilidade de RNA , Regiões 3' não Traduzidas , Células HeLa , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
8.
Physiol Behav ; 256: 113959, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36088981

RESUMO

Social cues modulate the neuroendocrine control of reproduction. However, the neural systems involved in the integration of social cues are not well described. Gonadotropin-releasing hormone 1 (GnRH1) cells in the preoptic area (POA) are the final common node that links the brain with peripheral reproductive physiology. These experiments investigated whether induction of the immediate early gene, EGR1, in anatomically localized GnRH1 cell populations in Border canaries is regulated by the social environment. First, we characterized behavioral modifications in singing behavior and found males paired with a female for 2 weeks significantly reduced many aspects of singing behavior. However, paired males had a significantly higher percentage of GnRH1 cells co-labeled with EGR1. The second experiment manipulated the social environment by pairing males and females in mixed sex dyads, same sex dyads or housed birds in isolation. Only when birds are paired in mixed sex dyads was there a significantly greater percentage of GnRH1 cells expressing EGR1 cells. Increased GnRH1-EGR1 co-expression was localized to the rostral POA. These data reveal that discrete GnRH1 cells are involved in the neural integration of specific social cues and support the hypothesis that the POA exhibits functional topography related to courtship and sexual behaviors.


Assuntos
Canários , Canto , Animais , Aves , Canários/fisiologia , Feminino , Genes Precoces , Hormônio Liberador de Gonadotropina/genética , Gonadotropinas , Masculino , Neurônios , Vocalização Animal
9.
Proc Natl Acad Sci U S A ; 119(38): e2123373119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095210

RESUMO

The ability of neurons to process and store salient environmental features underlies information processing in the brain. Long-term information storage requires synaptic plasticity and regulation of gene expression. While distinct patterns of activity have been linked to synaptic plasticity, their impact on immediate early gene (IEG) expression remains poorly understood. The activity regulated cytoskeleton associated (Arc) gene has received wide attention as an IEG critical for long-term synaptic plasticity and memory. Yet, to date, the transcriptional dynamics of Arc in response to compartment and input-specific activity is unclear. By developing a knock-in mouse to fluorescently tag Arc alleles, we studied real-time transcription dynamics after stimulation of dentate granule cells (GCs) in acute hippocampal slices. To our surprise, we found that Arc transcription displayed distinct temporal kinetics depending on the activation of excitatory inputs that convey functionally distinct information, i.e., medial and lateral perforant paths (MPP and LPP, respectively). Moreover, the transcriptional dynamics of Arc after synaptic stimulation was similar to direct activation of GCs, although the contribution of ionotropic glutamate receptors, L-type voltage-gated calcium channel, and the endoplasmic reticulum (ER) differed. Specifically, we observed an ER-mediated synapse-to-nucleus signal that supported elevations in nuclear calcium and, thereby, rapid induction of Arc transcription following MPP stimulation. By delving into the complex excitation-transcription coupling for Arc, our findings highlight how different synaptic inputs may encode information by modulating transcription dynamics of an IEG linked to learning and memory.


Assuntos
Proteínas do Citoesqueleto , Genes Precoces , Proteínas do Tecido Nervoso , Plasticidade Neuronal , Transcrição Genética , Animais , Proteínas do Citoesqueleto/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Plasticidade Neuronal/genética , Sinapses/metabolismo
10.
Mol Neurobiol ; 59(9): 5722-5733, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35789976

RESUMO

Amnesia is the inability to store new information and recall old memories. After the postulation of cholinergic hypothesis of geriatric memory dysfunction, the cholinergic signaling became a popular target to understand the underlying molecular mechanism of amnesia and its recovery. Scopolamine is a non-selective cholinergic receptor antagonist and induces amnesia through downregulation of synaptic plasticity genes including immediate early genes (IEGs). Scopolamine-induced amnesic mouse model is widely used to study the memory impairment that mimics the pathophysiology of aging, neurodegenerative, and neuropsychiatric disorders. However, a detailed understanding of cholinergic signaling-mediated regulation of plasticity-related gene expression remains elusive. Therefore, we have investigated the role of muscarinic acetylcholine receptors (mAChRs) and their downstream mediator protein kinase C (PKC) in the regulation of IEGs expression in amnesic mice hippocampus. Pilocarpine, a mAChRs agonist, was used to activate the cholinergic signaling in scopolamine-induced amnesia. Further, a PKC activator bryostatin 1 was used to understand the sole involvement of PKC as a downstream mediator of mAChRs-mediated signaling. Pilocarpine treatment significantly restored the scopolamine-induced impaired recognition memory and downregulated hippocampal IEGs expression and phosphorylation of ERK1/2 (extracellular signal-regulated kinase 1/2) and CREB (cAMP response element-binding protein). On the other hand, the bryostatin 1-mediated activation of PKC in scopolamine-induced amnesia selectively restored the hippocampal IEGs expression, recognition memory, and phosphorylation of ERK1/2 and CREB. Taken together, our findings suggest that mAChRs and their downstream mediator PKC regulate the hippocampal IEGs expression and ERK1/2-mediated CREB phosphorylation in scopolamine-induced amnesic mice.


Assuntos
Genes Precoces , Escopolamina , Amnésia/genética , Animais , Colinérgicos/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Hipocampo/metabolismo , Transtornos da Memória , Camundongos , Fosforilação , Pilocarpina , Proteína Quinase C/metabolismo , Receptores Muscarínicos/metabolismo , Escopolamina/farmacologia
11.
J Biol Chem ; 298(9): 102278, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35863435

RESUMO

Immediate early genes (IEGs) are transcribed in response to neuronal activity from sensory stimulation during multiple adaptive processes in the brain. The transcriptional profile of IEGs is indicative of the duration of neuronal activity, but its sensitivity to the strength of depolarization remains unknown. Also unknown is whether activity history of graded potential changes influence future neuronal activity. In this work with dissociated rat cortical neurons, we found that mild depolarization-mediated by elevated extracellular potassium (K+)-induces a wide array of rapid IEGs and transiently depresses transcriptional and signaling responses to a successive stimulus. This latter effect was independent of de novo transcription, translation, and signaling via calcineurin or mitogen-activated protein kinase. Furthermore, as measured by multiple electrode arrays and calcium imaging, mild depolarization acutely subdues subsequent spontaneous and bicuculline-evoked activity via calcium- and N-methyl-d-aspartate receptor-dependent mechanisms. Collectively, this work suggests that a recent history of graded potential changes acutely depress neuronal intrinsic properties and subsequent responses. Such effects may have several potential downstream implications, including reducing signal-to-noise ratio during synaptic plasticity processes.


Assuntos
Potenciais de Ação , Calcineurina , Genes Precoces , Neurônios , Transcrição Genética , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Bicuculina/farmacologia , Calcineurina/genética , Calcineurina/metabolismo , Cálcio/metabolismo , Antagonistas de Receptores de GABA-A/farmacologia , Genes Precoces/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Potássio/metabolismo , Potássio/farmacologia , Ratos , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo
12.
J Neuroendocrinol ; 34(9): e13182, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35841324

RESUMO

Gs-coupled GPCR-stimulated neuritogenesis in PC12 and NS-1 - cells depends on activation of the MAP kinase ERK. Here, we examine changes in ERK activation (phosphorylation), and the time course of ERK-dependent gene induction, to seek transcriptional determinants for this process. Quenching of ERK activation by inhibition of MEK with U0126 at any time point for at least 24 h following addition of PACAP resulted in arrest of neurite formation. Changes in the transcriptome profile throughout this time period revealed at least two phases of gene induction: an early phase dominated by induction of immediate-early genes, and a later phase of gene induction after 4-6 h of exposure to PACAP with persistent elevation of phospho-ERK levels. Genes induced by PACAP in both phases consisted in those whose induction was dependent on ERK (i.e., blocked by U0126), and some whose induction was blocked by the protein kinase A inhibitor H89. ERK-dependent "late gene" transcripts included Gpr50, implicated earlier in facilitation of NGF-induced neurite formation in NS-1 cells. Gpr50 induction by PACAP, but not NGF, was dependent on the guanine nucleotide exchange factor RapGEF2, which has been shown to be required for PACAP-induced neuritogenesis in NS-1 cells. Expression of a Gpr50-directed shRNA lowered basal levels of Gpr50 mRNA and attenuated Gpr50 mRNA and GPR50 protein induction by PACAP, with a corresponding attenuation of PACAP-induced neuritogenesis. Gs-GPCR-stimulated neuritogenesis first requires immediate-early gene induction, including that of Egr1 (Zif268/NGF1A/Krox24) as previously reported. This early phase of gene induction, however, is insufficient to maintain the neuritogenic process without ERK-dependent induction of additional late genes, including Gpr50, upon continuous exposure to neurotrophic neuropeptide. Early (Egr1) and late (Gpr50) gene induction by NGF, like that for PACAP, was inhibited by U0126, but was independent of RapGEF2, confirming distinct modes of ERK activation by Gs-coupled GPCRs and neurotrophic tyrosine receptor kinases, converging on a final common ERK-dependent signaling pathway for neuritogenesis.


Assuntos
Genes Precoces , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Animais , Benzoatos , Butadienos , Proteína 1 de Resposta de Crescimento Precoce/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Nitrilas , Células PC12 , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Ratos
13.
Sci Rep ; 12(1): 12834, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896679

RESUMO

Tight regulation of immediate early gene (IEG) expression is important for synaptic plasticity, learning, and memory. Recent work has suggested that DNA double strand breaks (DSBs) may have an adaptive role in post-mitotic cells to induce IEG expression. Physiological activity in cultured neurons as well as behavioral training leads to increased DSBs and subsequent IEG expression. Additionally, infusion of etoposide-a common cancer treatment that induces DSBs-impairs trace fear memory. Here, we assessed the effects of hippocampal infusion of 60 ng of etoposide on IEG expression, learning, and memory in 3-4 month-old C57Bl/6J mice. Etoposide altered expression of the immediate early genes cFos and Arc in the hippocampus and impaired hippocampus-dependent contextual fear memory. These data add to the growing evidence that DSBs play an important role in IEG expression, learning, and memory, opening avenues for developing novel treatment strategies for memory-related disorders.


Assuntos
Genes Precoces , Hipocampo , Animais , Etoposídeo/farmacologia , Medo/fisiologia , Hipocampo/metabolismo , Transtornos da Memória/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal
14.
Theriogenology ; 189: 70-76, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35732098

RESUMO

The present study evaluated expression patterns of chemokine (C-C motif) ligand 2 gene/Monocyte chemoattractant protein-1 gene (CCL2/MCP-1), prostaglandin F2 alpha receptor gene (PTGFR) and immediate early genes including nuclear receptor subfamily 4, group A, member 1 (NR4A1), early growth response 1 (EGR1) and FBJ murine osteosarcoma viral oncogene homolog (FOS) in cells of the bovine corpus luteum after intrauterine infusion of a low dose of prostaglandin F2α (PGF2A) aimed at enhancing our understanding of the mechanisms of luteolysis. Holstein dairy cows were superovulated (>6 corpora lutea [CL]) and on day 9 of the estrous cycle were infused with a low dose of PGF2A (0.5 mg PGF2A in 0.25 ml phosphate buffered saline) into the greater curvature of the uterine horn ipsilateral to the CL. Ultrasound-guided biopsy samples of different CL were collected at 0 min, 15 min, 30 min, 1h, 2h and 6h after PGF2A infusion. Expression profiles and localization of mRNA for PTGFR, CCL2/MCP-1, and immediate early genes (NR4A1, EGR1 and FOS), were investigated by using qPCR and in situ hybridization. The concentrations of early response genes including FOS, NR4A1, and EGR1 exhibited the greatest increase at 30 min after PGF2A, compared to other time points. Expression profile of CCL2 mRNA increased gradually after intrauterine infusion of PGF2A with maximal up-regulation for CCL2 at 6h. Abundance of PTGFR mRNA only increased at 15 min and significantly decreased at 6h, compared to 0 min. Cellular localizations of all studied genes except CCL2 (primarily localized to apparent immune cells) were predominantly visualized in large luteal cells. Interestingly, early response genes demonstrated a changing profile in cellular localization with initial responses appearing to be in both large luteal cells and endothelial cells, although no staining for PTGFR mRNA was observed in endothelial cells. Later, sustained responses, were only observed in large luteal cells, although PTGFR mRNA was decreasing in large luteal cells over time after PGF2A. The involvement of the immune system was also highlighted by the immediate increases in CCL2 mRNA that became much greater over time as there was an apparent influx of CCL2-positive immune cells. Thus, the temporal and cell-specific localization patterns for the studied mRNA demonstrate the complex pathways that are responsible for initiation of luteolysis in the bovine CL.


Assuntos
Dinoprosta , Genes Precoces , Animais , Bovinos , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Corpo Lúteo/fisiologia , Dinoprosta/metabolismo , Dinoprosta/farmacologia , Células Endoteliais , Feminino , Luteólise/fisiologia , Camundongos , RNA Mensageiro/metabolismo
15.
Cell Rep ; 39(8): 110857, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35613587

RESUMO

Protocadherin-19 (PCDH19) is a synaptic cell-adhesion molecule encoded by X-linked PCDH19, a gene linked with epilepsy. Here, we report a synapse-to-nucleus signaling pathway through which PCDH19 bridges neuronal activity with gene expression. In particular, we describe the NMDA receptor (NMDAR)-dependent proteolytic cleavage of PCDH19, which leads to the generation of a PCDH19 C-terminal fragment (CTF) able to enter the nucleus. We demonstrate that PCDH19 CTF associates with chromatin and with the chromatin remodeler lysine-specific demethylase 1 (LSD1) and regulates expression of immediate-early genes (IEGs). Our results are consistent with a model whereby PCDH19 favors maintenance of neuronal homeostasis via negative feedback regulation of IEG expression and provide a key to interpreting PCDH19-related hyperexcitability.


Assuntos
Caderinas , Epilepsia , Genes Precoces , Protocaderinas , Caderinas/genética , Caderinas/metabolismo , Cromatina/genética , Cromatina/metabolismo , Epilepsia/genética , Epilepsia/metabolismo , Regulação da Expressão Gênica , Humanos , Protocaderinas/genética , Protocaderinas/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais
16.
Behav Brain Res ; 428: 113863, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35351483

RESUMO

Neophobia - an animal's reluctance to approach novel objects, try new foods, or explore unfamiliar environments - affects whether animals can adapt to new environments and exploit novel resources. However, despite its importance, the neurobiological mechanisms underlying this personality trait are poorly understood. In this study, we examined regional brain activity using the expression of two immediate early genes (IEGs), ZENK and c-Fos, in response to novel objects or control conditions in captive house sparrows (Passer domesticus, n = 22). When exposed to novel objects, we predicted that we would see differential IEG activity in brain regions involved in regulating stress and emotion (hippocampus, medial ventral arcopallium, lateral septum), reward and learning (striatum), and executive function (NCL) between neophobic and non-neophobic individuals. To classify birds by phenotype, we used behavior trials that tested willingness to approach a food dish in the presence of several different novel objects, habituation to one novel object, and willingness to try several different novel foods. We then exposed birds to a new novel object or a control condition and assessed protein expression of two IEGs in neophobic vs non-neophobic individuals after this final exposure. An analysis of average sparrow feeding times in the presence of novel objects showed a bimodal distribution of neophobia behavior. There was also high repeatability of individual novel object responses, and average responses to all three trial types (novel object, novel food, and habituation to a novel object) were significantly correlated. Although we saw no differences between neophobic and non-neophobic birds in IEG expression in response to novel objects in any of the 6 brain regions examined, there was a significant global decrease in ZENK expression and a significant increase in c-Fos expression in the medial ventral arcopallium and the caudal hippocampus in response to novel objects compared to controls, suggesting that these two regions may be important in novelty detection and threat perception. Additionally, there was no object effect in the rostral hippocampus, which supports the hypothesis that the avian hippocampus may have a rostrocaudal functional gradient similar to the septotemporal gradient in mammals.


Assuntos
Pardais , Animais , Encéfalo/metabolismo , Corpo Estriado/metabolismo , Genes Precoces , Mamíferos/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Pardais/metabolismo
17.
Physiol Behav ; 250: 113782, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35314175

RESUMO

Male song in songbirds is a critical and elaborate signal for mate attraction. In many species female listeners respond to male song both behaviorally and physiologically (e.g. copulation solicitation displays and production of the immediate early gene ZENK in auditory regions). It is becoming increasingly well known that females in many species also sing. However, in common lab species, such as canaries (Serinus canaria), female song is limited and has been primarily studied in the context of administering of exogenous testosterone (T) to increase song rate and length. In this study we addressed to what extent female canary songs are masculinized by the administration of exogenous T based on the behavioral and physiological responses of avian receivers. Specifically, are T induced female songs sufficient to elicit courtship behaviors and auditory ZENK expression in female listeners? We found that female songs after 3 weeks of exogenous T were significantly longer and more complex than female songs after 12 weeks of exogenous T. Additionally, we found that playback of 3-week T song significantly increased sexual response behaviors and the expression of ZENK in the auditory brain regions of female listeners. Finally, we conclude that extended periods of T do not necessarily maintain the masculinization of female song.


Assuntos
Canários , Aves Canoras , Animais , Canários/fisiologia , Feminino , Genes Precoces , Masculino , Aves Canoras/fisiologia , Testosterona/farmacologia , Vocalização Animal/fisiologia
18.
Commun Biol ; 5(1): 130, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35165405

RESUMO

Free-flying bees learn efficiently to solve numerous visual tasks. Yet, the neural underpinnings of this capacity remain unexplored. We used a 3D virtual reality (VR) environment to study visual learning and determine if it leads to changes in immediate early gene (IEG) expression in specific areas of the bee brain. We focused on kakusei, Hr38 and Egr1, three IEGs that have been related to bee foraging and orientation, and compared their relative expression in the calyces of the mushroom bodies, the optic lobes and the rest of the brain after color discrimination learning. Bees learned to discriminate virtual stimuli displaying different colors and retained the information learned. Successful learners exhibited Egr1 upregulation only in the calyces of the mushroom bodies, thus uncovering a privileged involvement of these brain regions in associative color learning and the usefulness of Egr1 as a marker of neural activity induced by this phenomenon.


Assuntos
Corpos Pedunculados , Realidade Virtual , Animais , Abelhas/genética , Encéfalo/metabolismo , Genes Precoces , Aprendizagem , Corpos Pedunculados/metabolismo
19.
Oncotarget ; 13: 198-213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35106123

RESUMO

DNA double strand breaks (DSBs) have been highly studied in the context of cancers, as DSBs can lead to apoptosis or tumorigenesis. Several pharmaceuticals are widely used to target DSBs during cancer therapy. Amifostine (WR-2721) and etoposide are two commonly used drugs: amifostine reduces DSBs, whereas etoposide increases DSBs. Recently, a novel role for DSBs in immediate early gene expression, learning, and memory has been suggested. Neither amifostine nor etoposide have been assessed for their effects on learning and memory without confounding factors. Moreover, sex-dependent effects of these drugs have not been reported. We administered amifostine or etoposide to 3-4-month-old male and female C57Bl/6J mice before or after training in fear conditioning and assessed learning, memory, and immediate early genes. We observed sex-dependent baseline and drug-induced differences, with females expressing higher cFos and FosB levels than males. These were affected by both amifostine and etoposide. Post-training injections of amifostine affected long-term contextual fear memory; etoposide affected contextual and cued fear memory. These data support the hypothesis that DSBs contribute to learning and memory, and that these could play a part in cognitive side effects during common treatment regimens. The sex-dependent effects also highlight an important factor when considering treatment plans.


Assuntos
Amifostina , Neoplasias , Animais , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Etoposídeo/farmacologia , Feminino , Genes Precoces , Masculino , Memória de Longo Prazo , Camundongos , Preparações Farmacêuticas
20.
Cell Rep ; 38(6): 110332, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35139389

RESUMO

Endothelial cells (ECs) are phenotypically heterogeneous, mainly due to their dynamic response to the tissue microenvironment. Vascular endothelial cell growth factor (VEGF), the best-known angiogenic factor, activates calcium-nuclear factor of activated T cells (NFAT) signaling following acute angiogenic gene transcription. Here, we evaluate the global mapping of VEGF-mediated dynamic transcriptional events, focusing on major histone-code profiles using chromatin immunoprecipitation sequencing (ChIP-seq). Remarkably, the gene loci of immediate-early angiogenic transcription factors (TFs) exclusively acquire bivalent H3K4me3-H3K27me3 double-positive histone marks after the VEGF stimulus. Moreover, NFAT-associated Pax transactivation domain-interacting protein (PTIP) directs bivalently marked TF genes transcription through a limited polymerase II running. The non-canonical polycomb1 variant PRC1.3 specifically binds to and allows the transactivation of PRC2-enriched bivalent angiogenic TFs until conventional PRC1-mediated gene silencing is achieved. Knockdown of these genes abrogates post-natal aberrant neovessel formation via the selective inhibition of indispensable bivalent angiogenic TF gene transcription. Collectively, the reported dynamic histone mark landscape may uncover the importance of immediate-early genes and the development of advanced anti-angiogenic strategies.


Assuntos
Indutores da Angiogênese/metabolismo , Genes Precoces/genética , Histonas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Imunoprecipitação da Cromatina , Sequenciamento de Cromatina por Imunoprecipitação , Células Endoteliais/metabolismo , Epigênese Genética/genética , Inativação Gênica/fisiologia , Humanos , Camundongos , Neovascularização Patológica/genética , Regiões Promotoras Genéticas/genética
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