RESUMEN
Morphine, a typical opiate, is widely used for controlling pain but can lead to various side effects with long-term use, including addiction, analgesic tolerance, and hyperalgesia. At present, however, the mechanisms underlying the development of morphine analgesic tolerance are not fully understood. This tolerance is influenced by various opioid receptor and kinase protein modifications, such as phosphorylation and ubiquitination. Here, we established a murine morphine tolerance model to investigate whether and how S-nitrosoglutathione reductase (GSNOR) is involved in morphine tolerance. Repeated administration of morphine resulted in the down-regulation of GSNOR, which increased excessive total protein S-nitrosation in the prefrontal cortex. Knockout or chemical inhibition of GSNOR promoted the development of morphine analgesic tolerance and neuron-specific overexpression of GSNOR alleviated morphine analgesic tolerance. Mechanistically, GSNOR deficiency enhanced S-nitrosation of cellular protein kinase alpha (PKCα) at the Cys78 and Cys132 sites, leading to inhibition of PKCα kinase activity, which ultimately promoted the development of morphine analgesic tolerance. Our study highlighted the significant role of GSNOR as a key regulator of PKCα S-nitrosation and its involvement in morphine analgesic tolerance, thus providing a potential therapeutic target for morphine tolerance.
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Tolerancia a Medicamentos , Morfina , Proteína Quinasa C-alfa , Animales , Ratones , Morfina/farmacología , Proteína Quinasa C-alfa/metabolismo , Proteína Quinasa C-alfa/genética , Nitrosación , Aldehído Oxidorreductasas/metabolismo , Aldehído Oxidorreductasas/genética , Masculino , Ratones Noqueados , Analgésicos Opioides/farmacología , Modelos Animales de Enfermedad , Alcohol DeshidrogenasaRESUMEN
Wounding is one of the most common healthcare problems. Bioactive hydrogels have attracted much attention in first-aid hemostasis and wound healing due to their excellent biocompatibility, antibacterial properties, and pro-healing bioactivity. However, their applications are limited by inadequate mechanical properties. In this study, we first prepared edible rose-derived exosome-like nanoparticles (ELNs) and used them to encapsulate antimicrobial peptides (AMP), abbreviated as ELNs(AMP). ELNs(AMP) showed superior intracellular antibacterial activity, 2.5 times greater than AMP, in in vitro cell infection assays. We then prepared and tested an FDA-approved fibrin-gel of fibrinogen and thrombin encapsulating ELNs(AMP) and novobiocin sodium salt (NB) (ELNs(AMP)/NB-fibrin-gels). The fibrin gel showed a sustained release of ELNs(AMP) and NB over the eight days of testing. After spraying onto the skin, the formulation underwent in situ gelation and developed a stable patch with excellent hemostatic performance in a mouse liver injury model with hemostasis in 31 s, only 35.6 % of the PBS group. The fibrin gel exhibited pro-wound healing properties in the mouse-infected skin defect model. The thickness of granulation tissue and collagen of the ELNs(AMP)/NB-fibrin-gels group was 4.00, 6.32 times greater than that of the PBS group. In addition, the ELNs(AMP)/NB-fibrin-gels reduced inflammation (decreased mRNA levels of TNF-α, IL-1ß, IL6, MCP1, and CXCL1) at the wound sites and demonstrated a biocompatible and biosafe profile. Thus, we have developed a hydrogel system with excellent hemostatic, antibacterial, and pro-wound healing properties, which may be a candidate for next-generation tissue regeneration with a wide clinical application for first-aid hemostasis and infected wound healing.
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Antibacterianos , Exosomas , Fibrina , Hemostasis , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Animales , Hemostasis/efectos de los fármacos , Ratones , Fibrina/química , Antibacterianos/farmacología , Antibacterianos/química , Exosomas/metabolismo , Péptidos Antimicrobianos/química , Péptidos Antimicrobianos/farmacología , Humanos , Infección de Heridas/tratamiento farmacológico , Nanopartículas/química , Geles/química , Hidrogeles/química , Hidrogeles/farmacología , MasculinoRESUMEN
Hyperactivation of the NLRP3 inflammasome has been implicated in the pathogenesis of numerous diseases. However, the precise molecular mechanisms that modulate the transcriptional regulation of NLRP3 remain largely unknown. In this study, we demonstrated that S-nitrosoglutathione reductase (GSNOR) deficiency in macrophages leads to significant increases in the Nlrp3 and Il-1ß expression levels and interleukin-1ß (IL-1ß) secretion in response to NLRP3 inflammasome stimulation. Furthermore, in vivo experiments utilizing Gsnor-/- mice revealed increased disease severity in both lipopolysaccharide (LPS)-induced septic shock and dextran sodium sulfate (DSS)-induced colitis models. Additionally, we showed that both LPS-induced septic shock and DSS-induced colitis were ameliorated in Gsnor-/- Nlrp3-/- double-knockout (DKO) mice. Mechanistically, GSNOR deficiency increases the S-nitrosation of mitogen-activated protein kinase 14 (MAPK14) at the Cys211 residue and augments MAPK14 kinase activity, thereby promoting Nlrp3 and Il-1ß transcription and stimulating NLRP3 inflammasome activity. Our findings suggested that GSNOR is a regulator of the NLRP3 inflammasome and that reducing the level of S-nitrosylated MAPK14 may constitute an effective strategy for alleviating diseases associated with NLRP3-mediated inflammation.
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Colitis , Sulfato de Dextran , Inflamasomas , Interleucina-1beta , Lipopolisacáridos , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Ratones , Aldehído Oxidorreductasas/metabolismo , Aldehído Oxidorreductasas/genética , Colitis/inducido químicamente , Colitis/patología , Colitis/inmunología , Inflamasomas/metabolismo , Interleucina-1beta/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Macrófagos/inmunología , Nitrosación , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Choque Séptico/metabolismo , Choque Séptico/inducido químicamente , Proteína Quinasa 14 Activada por Mitógenos/metabolismoRESUMEN
The lysosome-targeting chimera (LYTAC) approach has shown promise for the targeted degradation of secreted and membrane proteins via lysosomes. However, there have been challenges in design, development, and targeting. Here, we have designed a genetically engineered transferrin receptor (TfR)-mediated lysosome-targeting chimera (TfR-LYTAC) that is efficiently internalized via TfR-mediate endocytosis and targets PD-L1 for lysosomal degradation in cultured cells but not in vivo due to short half-life and poor tumor targeting. A delivery platform was developed by fusing TfR-LYTAC to the surface of bacterial outer membrane vesicles (OMVs). The engineered OMV-LYTAC combines PD-1/PD-L1 pathway inhibition with LYTAC and immune activation by bacterial OMVs. OMV-LYTAC significantly reduced tumor growth in vivo. We have provided a modular and simple genetic strategy for lysosomal degradation as well as a delivery platform for in vivo tumor targeting. The study paves the way for the targeting and degradation of extracellular proteins using the TfR-LYTAC system.
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Inmunoterapia , Lisosomas , Receptores de Transferrina , Receptores de Transferrina/metabolismo , Receptores de Transferrina/inmunología , Lisosomas/metabolismo , Humanos , Animales , Ratones , Membrana Externa Bacteriana/metabolismo , Femenino , Línea Celular Tumoral , Ratones Endogámicos BALB C , Antígeno B7-H1/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/químicaRESUMEN
INTRODUCTION: The APOE gene is the strongest genetic risk factor for late-onset Alzheimer's Disease (LOAD). However, the gene regulatory mechanisms at this locus have not been fully characterized. METHODS: To identify novel AD-linked functional elements within the APOE locus, we integrated SNP variants with RNA-seq, DNA methylation, and ChIP-seq data from human postmortem brains. RESULTS: We identified an AD-linked APOE transcript (jxn1.2.2) observed in the dorsolateral prefrontal cortex (DLPFC). The APOE jxn1.2.2 transcript is associated with brain neuropathological features in DLPFC. We prioritized an independent functional SNP, rs157580, significantly associated with jxn1.2.2 transcript abundance and DNA methylation levels. rs157580 is located within active chromatin regions and predicted to affect brain-related transcriptional factors binding affinity. rs157580 shared the effects on the jxn1.2.2 transcript between European and African ethnic groups. DISCUSSION: The novel APOE functional elements provide potential therapeutic targets with mechanistic insight into the disease's etiology.
RESUMEN
The S-nitrosoglutathione reductase (GSNOR) is a key denitrosating enzyme that regulates protein S-nitrosation, a process which has been found to be involved in the pathogenesis of Parkinson's disease (PD). However, the physiological function of GSNOR in PD remains unknown. In a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model, we found that GSNOR expression was significantly increased and accompanied by autophagy mediated by MPTP-induced cyclin dependent kinase 5 (CDK5), behavioral dyskinesias and dopaminergic neuron loss. Whereas, knockout of GSNOR, or treatment with the GSNOR inhibitor N6022, alleviated MPTP-induced PD-like pathology and neurotoxicity. Mechanistically, deficiency of GSNOR inhibited MPTP-induced CDK5 kinase activity and CDK5-mediated autophagy by increasing S-nitrosation of CDK5 at Cys83. Our study indicated that GSNOR is a key regulator of CDK5 S-nitrosation and is actively involved in CDK5-mediated autophagy induced by MPTP.
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Alcohol Deshidrogenasa/metabolismo , Intoxicación por MPTP , Enfermedad de Parkinson , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Autofagia , Quinasa 5 Dependiente de la Ciclina/genética , Quinasa 5 Dependiente de la Ciclina/metabolismo , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Intoxicación por MPTP/metabolismo , Ratones , Ratones Endogámicos C57BL , Nitrosación , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismoRESUMEN
Innate immunity is the first line of host defense against pathogens. This process is modulated by multiple antiviral protein modifications, such as phosphorylation and ubiquitination. Here, we showed that cellular S-nitrosoglutathione reductase (GSNOR) is actively involved in innate immunity activation. GSNOR deficiency in mouse embryo fibroblasts (MEFs) and RAW264.7 macrophages reduced the antiviral innate immune response and facilitated herpes simplex virus-1 (HSV-1) and vesicular stomatitis virus (VSV) replication. Concordantly, HSV-1 infection in Gsnor-/- mice and wild-type mice with GSNOR being inhibited by N6022 resulted in higher mortality relative to the respective controls, together with severe infiltration of immune cells in the lungs. Mechanistically, GSNOR deficiency enhanced cellular TANK-binding kinase 1 (TBK1) protein S-nitrosation at the Cys423 site and inhibited TBK1 kinase activity, resulting in reduced interferon production for antiviral responses. Our study indicated that GSNOR is a critical regulator of antiviral responses and S-nitrosation is actively involved in innate immunity.
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Alcohol Deshidrogenasa/metabolismo , Cisteína , Herpesvirus Humano 1 , Inmunidad Innata , Animales , Ratones , Nitrosación , Proteínas Serina-Treonina Quinasas/genéticaRESUMEN
Drug addiction is a global health problem and continues to place an enormous financial burden on society. This addiction is characterized by drug dependence sensitization and craving. Morphine has been widely used for pain relief, but chronic administration of morphine causes analgesic tolerance, hyperalgesia, and addiction, all of which limit its clinical usage. Alterations of multiple molecular pathways have been reported to be involved in the development of drug addiction, including mitochondrial dysfunction, excessive oxidative stress and nitric oxide stress, and increased levels of apoptosis, autophagy, and neuroinflammation. Preclinical and clinical studies have shown that the co-administration of melatonin with morphine leads to a reversal of these affected pathways. In addition, murine models have shown that melatonin improves morphine-induced analgesic tolerance and addictive behaviors, such as behavioral sensitization, reward effect, and physical dependence. In this review, we attempt to summarize the recent findings about the beneficial effect and molecular mechanism of melatonin on mitochondrial dysfunction, uncontrolled autophagy, and neuroinflammation in morphine addiction and morphine analgesic tolerance. We propose that melatonin might be a useful supplement in the treatment opiate abuse.
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Tolerancia a Medicamentos , Melatonina/farmacología , Dependencia de Morfina/fisiopatología , Morfina/farmacología , Fármacos Neuroprotectores/farmacología , Autofagia/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos , Dimensión del DolorRESUMEN
Morphine is frequently used for pain relief, but long-term morphine therapy in patients with chronic pain results in analgesic tolerance and hyperalgesia. There are no effective therapeutic treatments that limit these detrimental side effects. We found pretreatment with melatonin could decrease morphine-induced analgesic tolerance. There was a significant activation of the NLRP3 inflammasome in the prefrontal cortex and the peripheral blood of morphine-treated mice compared to control animals, which could be blocked by melatonin. The inflammasome activation induced by morphine was mediated by the microglia. SiRNA knockdown or pharmacological inhibition of the NLRP3 abolished the morphine-induced inflammasome activation. Co-administration of melatonin and low-dose morphine had better analgesia effects in the murine models of pain and led to a lower NLRP3 inflammasome activity in brain tissues. Mice deficient for Nlrp3 had a higher nociceptive threshold and were less sensitive to develop morphine-induced analgesic tolerance and acetic acid-induced pain relative to wild-type animals. Concordantly, we observed a significantly elevated level of serum IL-1ß, which indicates an increase of NLRP3 inflammasome activity associated with the reduced level of serum melatonin, in heroin-addicted patients relative to healthy individuals. Our results provide a solid basis for conducting a clinical trial with the co-administration of melatonin and morphine for the relief of severe pain.
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Melatonina , Morfina , Analgésicos , Animales , Humanos , Inflamasomas , Melatonina/farmacología , Ratones , Morfina/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/genéticaRESUMEN
Alzheimer disease (AD) is the most common neurodegenerative disease. An imbalance between the production and clearance of Aß (amyloid beta) is considered to be actively involved in AD pathogenesis. Macroautophagy/autophagy is a major cellular pathway leading to the removal of aggregated proteins, and upregulation of autophagy represents a plausible therapeutic strategy to combat overproduction of neurotoxic Aß. PPARA/PPARα (peroxisome proliferator activated receptor alpha) is a transcription factor that regulates genes involved in fatty acid metabolism and activates hepatic autophagy. We hypothesized that PPARA regulates autophagy in the nervous system and PPARA-mediated autophagy affects AD. We found that pharmacological activation of PPARA by the PPARA agonists gemfibrozil and Wy14643 induces autophagy in human microglia (HM) cells and U251 human glioma cells stably expressing the human APP (amyloid beta precursor protein) mutant (APP-p.M671L) and this effect is PPARA-dependent. Administration of PPARA agonists decreases amyloid pathology and reverses memory deficits and anxiety symptoms in APP-PSEN1ΔE9 mice. There is a reduced level of soluble Aß and insoluble Aß in hippocampus and cortex tissues from APP-PSEN1ΔE9 mice after treatment with either gemfibrozil or Wy14643, which promoted the recruitment of microglia and astrocytes to the vicinity of Aß plaques and enhanced autophagosome biogenesis. These results indicated that PPARA is an important factor regulating autophagy in the clearance of Aß and suggested gemfibrozil be assessed as a possible treatment for AD.Abbreviation: Aß: amyloid beta; ACTB: actin beta; ADAM10: ADAM metallopeptidase domain 10; AD: Alzheimer disease; AIF1/IBA1: allograft inflammatory factor 1; ANOVA: analysis of variance; APOE: apolipoprotein E; APP: amyloid beta precursor protein; APP-PSEN1ΔE9: APPswe/PSEN1dE9; BAFA1: bafilomycin A1; BDNF: brain derived neurotrophic factor; BECN1: beclin 1; CD68: CD68 molecule; CREB1: cAMP responsive element binding protein 1; DAPI: 4',6-diamidino-2-phenylindole; DLG4/PSD-95: discs large MAGUK scaffold protein 4; DMSO: dimethyl sulfoxide; ELISA: enzyme linked immunosorbent assay; FDA: U.S. Food and Drug Administration; FKBP5: FK506 binding protein 5; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; gemfibrozil: 5-(2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid; GFAP: glial fibrillary acidic protein; GLI2/THP1: GLI family zinc finger 2; HM: human microglia; IL6: interleukin 6; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; NC: negative control; OQ: opposite quadrant; PPARA/PPARα, peroxisome proliferator activated receptor alpha; PSEN1/PS1: presenilin 1; SEM: standard error of the mean; SQSTM1: sequestosome 1; SYP: synaptophysin; TFEB: transcription factor EB; TNF/TNF-α: tumor necrosis factor; TQ: target quadrant; WT: wild type; Wy14643: 2-[4-chloro-6-(2,3-dimethylanilino)pyrimidin-2-yl]sulfanylacetic acid.
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Enfermedad de Alzheimer/patología , Autofagia/fisiología , PPAR alfa/metabolismo , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Autofagia/genética , Disfunción Cognitiva/metabolismo , Modelos Animales de Enfermedad , Humanos , Ratones , Microglía/metabolismo , Enfermedades Neurodegenerativas/metabolismo , PPAR alfa/genética , Placa Amiloide/metabolismoRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disease with increasing incidence across the world and no cure at the present time. An ideal animal model would facilitate the understanding of the pathogenesis of AD and discovery of potential therapeutic targets. The Chinese tree shrew (Tupaia belangeri chinensis) has a closer genetic affinity to primates relative to rodents, and can attain ages of 8 years or older, which represents another advantage for the study of neurodegenerative diseases such as AD compared to primates. Here, we analyzed 131 AD-related genes in the Chinese tree shrew brain tissues based on protein sequence identity, positive selection, mRNA, and protein expression by comparing with those of human, rhesus monkey, and mouse. In particular, we focused on the Aß and neurofibrillary tangles formation pathways, which are crucial to AD pathogenesis. The Chinese tree shrew had a generally higher sequence identity with human than that of mouse versus human for the AD pathway genes. There was no apparent selection on the tree shrew lineage for the AD-related genes. Moreover, expression pattern of the Aß and neurofibrillary tangle formation pathway genes in tree shrew brain tissues resembled that of human brain tissues, with a similar aging-dependent effect. Our results provided an essential genetic basis for future AD research using the tree shrew as a viable model.
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Enfermedad de Alzheimer/genética , Modelos Animales de Enfermedad , Tupaia/genética , Secuencia de Aminoácidos , Animales , Investigación Biomédica , Perfilación de la Expresión Génica , Humanos , Masculino , RatonesRESUMEN
The geographic origin and migration of the brown rat (Rattus norvegicus) remain subjects of considerable debate. In this study, we sequenced whole genomes of 110 wild brown rats with a diverse world-wide representation. We reveal that brown rats migrated out of southern East Asia, rather than northern Asia as formerly suggested, into the Middle East and then to Europe and Africa, thousands of years ago. Comparison of genomes from different geographical populations reveals that many genes involved in the immune system experienced positive selection in the wild brown rat.
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Filogeografía/métodos , Ratas/genética , África , Animales , Asia Sudoriental/epidemiología , Evolución Biológica , Europa (Continente) , Evolución Molecular , Variación Genética/genética , Genética de Población , Genoma/genética , Medio Oriente , Filogenia , Secuenciación Completa del Genoma/métodosRESUMEN
The laboratory rat, widely used in biomedical research, is domesticated from wild brown rat. The origin and genetic mechanism underlying domestication of the laboratory rat remain largely elusive. In the present study, large scale genomes supported a single origin for the laboratory rat, possibly from a sister group to wild rats from Europe/Africa/Middle East. Genomic and transcriptomic analyses uncovered many artificially selected genes (e.g., FOXP2, B3GAT1, and CLOCK) involved in the nervous system. These genes associate with learning ability and regulation of circadian rhythm, which likely enabled the successful domestication of the laboratory rat. Particularly, many genes, including mitochondrial genes responsible for energy metabolism, displayed a substantially increased expression in the brain of laboratory rats compared with wild rats. Our findings demystify the origin and evolution of this model animal, and provide insight into the process of its domestication.
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Animales Domésticos/genética , Ratas/genética , Animales , Evolución Biológica , Proteínas CLOCK/genética , Domesticación , Metabolismo Energético/genética , Evolución Molecular , Factores de Transcripción Forkhead/genética , Genoma/genética , Genómica/métodos , Aprendizaje/fisiología , Filogenia , Selección Genética/genéticaRESUMEN
The molecular basis of chronic morphine exposure remains unknown. In this study, we hypothesized that macroautophagy/autophagy of dopaminergic neurons would mediate the alterations of neuronal dendritic morphology and behavioral responses induced by morphine. Chronic morphine exposure caused Atg5 (autophagy-related 5)- and Atg7 (autophagy-related 7)-dependent and dopaminergic neuron-specific autophagy resulting in decreased neuron dendritic spines and the onset of addictive behaviors. In cultured primary midbrain neurons, morphine treatment significantly reduced total dendritic length and complexity, and this effect could be reversed by knockdown of Atg5 or Atg7. Mice deficient for Atg5 or Atg7 specifically in the dopaminergic neurons were less sensitive to developing a morphine reward response, behavioral sensitization, analgesic tolerance and physical dependence compared to wild-type mice. Taken together, our findings suggested that the Atg5- and Atg7-dependent autophagy of dopaminergic neurons contributed to cellular and behavioral responses to morphine and may have implications for the future treatment of drug addiction.
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Proteína 5 Relacionada con la Autofagia/metabolismo , Proteína 7 Relacionada con la Autofagia/metabolismo , Autofagia , Conducta Animal , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Morfina/farmacología , Animales , Autofagia/efectos de los fármacos , Proteína 5 Relacionada con la Autofagia/deficiencia , Proteína 7 Relacionada con la Autofagia/deficiencia , Forma de la Célula/efectos de los fármacos , Neuronas Dopaminérgicas/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Mesencéfalo/citología , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Biológicos , Nocicepción/efectos de los fármacos , Células PC12 , RatasRESUMEN
Body size is the most important economic trait for animal production and breeding. Several hundreds of loci have been reported to be associated with growth trait and body weight in chickens. The loci are mapped to large genomic regions due to the low density and limited number of genetic markers in previous studies. Herein, we employed comparative population genomics to identify genetic basis underlying the small body size of Yuanbao chicken (a famous ornamental chicken) based on 89 whole genomes. The most significant signal was mapped to the BMP10 gene, whose expression was upregulated in the Yuanbao chicken. Overexpression of BMP10 induced a significant decrease in body length by inhibiting angiogenic vessel development in zebrafish. In addition, three other loci on chromosomes 1, 2, and 24 were also identified to be potentially involved in the development of body size. Our results provide a paradigm shift in identification of novel loci controlling body size variation, availing a fast and efficient strategy. These loci, particularly BMP10, add insights into ongoing research of the evolution of body size under artificial selection and have important implications for future chicken breeding.
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Animales Domésticos/genética , Tamaño Corporal/genética , Pollos/genética , Genética de Población , Animales , Emparejamiento Base/genética , Proteínas Morfogenéticas Óseas/genética , Cromosomas/genética , Sitios Genéticos , Genómica , Neovascularización Fisiológica/genética , Filogenia , Polimorfismo de Nucleótido Simple/genética , Pez Cebra/anatomía & histología , Pez Cebra/genéticaRESUMEN
As noted by Darwin, chickens have the greatest phenotypic diversity of all birds, but an interesting evolutionary difference between domestic chickens and their wild ancestor, the Red Junglefowl, is their comparatively weaker vision. Existing theories suggest that diminished visual prowess among domestic chickens reflect changes driven by the relaxation of functional constraints on vision, but the evidence identifying the underlying genetic mechanisms responsible for this change has not been definitively characterized. Here, a genome-wide analysis of the domestic chicken and Red Junglefowl genomes showed significant enrichment for positively selected genes involved in the development of vision. There were significant differences between domestic chickens and their wild ancestors regarding the level of mRNA expression for these genes in the retina. Numerous additional genes involved in the development of vision also showed significant differences in mRNA expression between domestic chickens and their wild ancestors, particularly for genes associated with phototransduction and photoreceptor development, such as RHO (rhodopsin), GUCA1A, PDE6B and NR2E3. Finally, we characterized the potential role of the VIT gene in vision, which experienced positive selection and downregulated expression in the retina of the village chicken. Overall, our results suggest that positive selection, rather than relaxation of purifying selection, contributed to the evolution of vision in domestic chickens. The progenitors of domestic chickens harboring weaker vision may have showed a reduced fear response and vigilance, making them easier to be unconsciously selected and/or domesticated.
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Animales Domésticos/genética , Evolución Biológica , Pollos/genética , Domesticación , Aves de Corral/genética , Selección Genética , Visión Ocular/genética , Animales , Técnicas de Silenciamiento del Gen , Genoma , Ratones , Morfolinos/farmacología , Pez Cebra/genéticaRESUMEN
Autophagy is involved in the pathogenesis of neurodegenerative diseases including Parkinson disease (PD). However, little is known about the regulation of autophagy in neurodegenerative process. In this study, we characterized aberrant activation of autophagy induced by neurotoxin 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) and demonstrated that melatonin has a protective effect on neurotoxicity. We found an excessive activation of autophagy in monkey brain tissues and C6 cells, induced by MPTP, which is mediated by CDK5 (cyclin-dependent kinase 5). MPTP treatment significantly reduced total dendritic length and dendritic complexity of cultured primary cortical neurons and melatonin could reverse this effect. Decreased TH (tyrosine hydroxylase)-positive cells and dendrites of dopaminergic neurons in the substantia nigra pars compacta (SNc) were observed in MPTP-treated monkeys and mice. Along with decreased TH protein level, we observed an upregulation of CDK5 and enhanced autophagic activity in the striatum of mice with MPTP injection. These changes could be salvaged by melatonin treatment or knockdown of CDK5. Importantly, melatonin or knockdown of CDK5 reduced MPTP-induced SNCA/α-synuclein aggregation in mice, which is widely thought to trigger the pathogenesis of PD. Finally, melatonin or knockdown of CDK5 counteracted the PD phenotype in mice induced by MPTP. Our findings uncover a potent role of CDK5-mediated autophagy in the pathogenesis of PD, and suggest that control of autophagic pathways may provide an important clue for exploring potential target for novel therapeutics of PD.
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1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Autofagia/efectos de los fármacos , Quinasa 5 Dependiente de la Ciclina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Melatonina/farmacología , alfa-Sinucleína/metabolismo , Animales , Autofagia/fisiología , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Haplorrinos , Ratones , Neurotoxinas/farmacología , Enfermedad de Parkinson/metabolismoRESUMEN
BACKGROUND: Telomerase reverse transcriptase (TERT) and cleft lip and palate trans-membrane 1 like (CLPTM1L) genes located on chromosome 5p15.33 are known to influence the susceptibility to various cancers. Here, we examined the association of TERT and CLPTM1L single nucleotide polymorphisms (SNPs) with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Genotyping of TERT SNP rs2736098 and CLPTM1L SNP rs401681 was performed using TaqMan allelic discrimination assays in a case-control study of 201 HCC cases and 210 controls in a Chinese male population. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression analyses. RESULTS: Both the rs2736098 T allele of TERT and the rs401681 T allele of CLPTM1L were associated with a significantly increased risk of HCC (adjusted odds ratio [OR]=1.605, 95% confidence interval [CI]=1.164-2.213; adjusted OR=1.399, 95%CI=1.002-1.955, respectively). Individuals carrying both TERT and CLPTM1L risk genotypes had an even higher risk of HCC (adjusted OR=4.420, 95%CI= 2.319-8.425). The TERT rs2736098 T allele was also significantly associated with the level of the HCC clinical indicator alpha-fetoprotein (P=0.026). CONCLUSIONS: Our results show that genetic variants of TERT and CLPTM1L may contribute to HCC susceptibility in Chinese males.