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Vocal learning is thought to have evolved in 3 orders of birds (songbirds, parrots, and hummingbirds), with each showing similar brain regions that have comparable gene expression specializations relative to the surrounding forebrain motor circuitry. Here, we searched for signatures of these same gene expression specializations in previously uncharacterized brains of 7 assumed vocal non-learning bird lineages across the early branches of the avian family tree. Our findings using a conserved marker for the song system found little evidence of specializations in these taxa, except for woodpeckers. Instead, woodpeckers possessed forebrain regions that were anatomically similar to the pallial song nuclei of vocal learning birds. Field studies of free-living downy woodpeckers revealed that these brain nuclei showed increased expression of immediate early genes (IEGs) when males produce their iconic drum displays, the elaborate bill-hammering behavior that individuals use to compete for territories, much like birdsong. However, these specialized areas did not show increased IEG expression with vocalization or flight. We further confirmed that other woodpecker species contain these brain nuclei, suggesting that these brain regions are a common feature of the woodpecker brain. We therefore hypothesize that ancient forebrain nuclei for refined motor control may have given rise to not only the song control systems of vocal learning birds, but also the drumming system of woodpeckers.
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Aves Canoras , Animais , Mapeamento Encefálico , Núcleo Celular , Masculino , Prosencéfalo , Vocalização AnimalRESUMO
Traumatic brain injury (TBI) is one of the major causes of death and disability worldwide. Novel and effective therapy is needed to prevent the secondary spread of damage beyond the initial injury. The aim of this study was to investigate whether berberine has a neuroprotective effect on secondary injury post-TBI, and to explore its potential mechanism in this protection. The mice were randomly divided into Sham-saline, TBI-saline and TBI-Berberine (50 mg/kg). TBI was induced by Feeney's weight-drop technique. Saline or berberine was administered via oral gavage starting 1 h post-TBI and continuously for 21 days. Motor coordination, spatial learning and memory were assessed using beam-walking test and Morris water maze test, respectively. Brain sections were processed for lesion volume assessment, and expression of neuronal nuclei (NeuN), cyclooxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS), 8-hydroxy-2-deoxyguanosine (8-OHdG), ionized calcium-binding adapter molecule 1 (Iba1) and glial fibrillary acidic protein (GFAP) were detected via immunohistochemistry and immunofluorescence. There were statistically significant improvement in motor coordination, spatial learning and memory in the TBI-Berberine group, compared to the TBI-saline group. Treatment with berberine significantly reduced cortical lesion volume, neuronal loss, COX-2, iNOS and 8-OHdG expression in both the cortical lesion border zone (LBZ) and ipsilateral hippocampal CA1 region (CA1), compared to TBI-saline. Berberine treatment also significantly decreased Iba1- and GFAP-positive cell number in both the cortical LBZ and ipsilateral CA1, relative to saline controls. These results indicated that berberine exerted neuroprotective effects on secondary injury in mice with TBI probably through anti-oxidative and anti-inflammatory properties.
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Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Berberina/farmacologia , Lesões Encefálicas Traumáticas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismoRESUMO
Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b). We found that these genes have a strong diurnal rhythmic transcription during light-dark cycles but not in constant darkness. An oscillation in pcna transcription was also observed during light-dark cycles, but again not in constant darkness. Our results also indicate an association between Clock proteins and the upstream region of pcna (proliferating cellular nuclear antigen) gene. A luciferase reporter assay conducted in an inducible clock knockdown cell line further demonstrated that the mutation on predicted E-Boxes in pcna promoter region significantly attenuated the transcriptional activation induced by Clock protein. These results suggested that the diurnal rhythmic expression of clock genes in A. burtoni retina could be light dependent and might contribute to the daily regulation of the proliferation of the retina progenitors through key components of cell cycle machinery, for instance, pcna.
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Proteínas CLOCK/genética , Regulação da Expressão Gênica , Antígeno Nuclear de Célula em Proliferação/genética , RNA/genética , Retina/metabolismo , Animais , Western Blotting , Proteínas CLOCK/biossíntese , Divisão Celular , Linhagem Celular , Proliferação de Células , Ciclídeos , Ritmo Circadiano/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Luz , Camundongos , Modelos Animais , Fotoperíodo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Retina/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcrição GênicaRESUMO
Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system 'maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of 'reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well-annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross-species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution.
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Evolução Biológica , Mapeamento Encefálico , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Anatomia Comparada , Animais , Humanos , Especificidade da EspécieRESUMO
INTRODUCTION: Dysregulated genes in glucose transport and metabolize pathways have been found in patients with Gestational diabetes (GDM), but the underlying mechanisms were still unclear. MATERIALS AND METHODS: Placental villous samples were collected from 31 patients with GDM and 20 healthy controls. The expression of GLUT1, GLUT4, GLUT9 and HK2 was examined by immunoblotting and qRT-PCR. The miRNAs have the potential targeting GLUT1 and HK2 were predicted using online bioinformatics tool: TargetScan. The interaction between miRNAs and target genes were confirmed by dual luciferase assay and immunoblotting. The function of miR-9 and miR-22 on glucose metabolism was examined by glucose uptake assay and lactate secretion assay. RESULTS: GLUT1 and HK2 proteins level was found upregulated in patients with GDM, but the mRNA level was not significantly changed. Predicted by using bioinformatics tools and confirmed by dual luciferase assay and immunoblotting, GLUT1 was identified as a target of miR-9 and miR-22, whereas HK2 was identified as a target of miR-9. MiR-9 and miR-22 level was found reduced in the placenta villous and negatively correlated with the expression of GLUT1 and HK2. Functional studies indicated that miR-9 and miR-22 inhibitors upregulated the expression of GLUT1 and HK2, and then increased the glucose uptake, lactate secretion, cell viability and repressed apoptosis in primary syncytiotrophoblasts (STBs) and HTR8/SVneo cells. DISCUSSION: The upregulation of GLUT1 and HK2 in the placenta, which is induced by miR-9 and miR-22 reduction, contributes to the disordered glucose metabolism in patients with GDM.
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Diabetes Gestacional/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Hexoquinase/metabolismo , MicroRNAs/metabolismo , Placenta/metabolismo , Adulto , Apoptose/fisiologia , Diabetes Gestacional/genética , Feminino , Regulação da Expressão Gênica , Transportador de Glucose Tipo 1/genética , Hexoquinase/genética , Humanos , MicroRNAs/genética , Gravidez , Trofoblastos/metabolismo , Adulto JovemRESUMO
Higher education, which has the function of cultivating human capital, has already become a key focus of developed countries around the world. From ministries of education to higher education institutions, many bodies are dedicated to enhancing student learning outcomes. However, social and educational problems derived from disadvantaged groups have long been hindering the development of individuals and the whole country. This study examines the learning motivations of economically disadvantaged versus non-disadvantaged college students and evaluates the relationship between learning modes and learning outcomes from a self-determination theory (SDT) perspective. In this study, 817 valid questionnaires were collected to compare the two sample groups in terms of learning path. The results show that non-economically disadvantaged students have superior outcomes compared to disadvantaged students in terms of role identity, academic identity, explorative learning, exploitative learning, and cognitive and non-cognitive gains. In regard to path analysis, economically disadvantaged students are significantly superior to non-disadvantaged students in the face of positive influence of academic identity on different learning modes and positive influence of explorative learning on cognitive and non-cognitive gains. Finally, based on the conclusions, this study proposes some suggestions specific to theoretical mode for future study.
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[This corrects the article DOI: 10.3389/fpsyg.2020.00231.].
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This study was conducted from the strategic marketing perspective to test the impact of brand relationship types on brand loyalty. We also test three path effects of brand love and brand trust. Data were collected from three metropolitan customers who use tablet PCs. We obtained 383 valid samples, giving a valid response rate of 89%. Data analysis was performed with SmartPLS2.0 and SPSS 23.0 to test the proposed model. The results indicate that an expressive brand relationship significantly predicts brand trust and brand loyalty. In turn, brand trust has a positive influence on brand love, while brand awareness and brand love influence attitudinal and behavioral loyalty. Expressive brand relationship has two indirect mediating affects via brand trust and brand love, which influence brand loyalty. Finally, we suggest managerial implications and directions for future research.
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Previous studies of the relationship between job security and job satisfaction were mostly conducted on research samples in Asia from the perspective of oriental culture; however, under the same cultural background, different social systems might lead to different cognition outcomes. Therefore, this study examines the job security and organizational support of Taiwan and mainland China employees from the perspectives of competence enhancement motivation, and investigates the relationship between employability and job satisfaction. Adopting judgmental sampling, a total of 1307 valid questionnaires were collected from Taiwan and mainland China employees. The path relationship of the two groups was examined through structural equation modeling (SEM) by using analysis of moment structure (AMOS). Results show that job security and organizational support are positive for employability and job satisfaction. Employability has a positive influence on job satisfaction. Additionally, employability has a mediating effect of job security and organizational support on job satisfaction.
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Emprego , Satisfação no Emprego , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Inquéritos e Questionários , Taiwan , Adulto JovemRESUMO
Corticotropin-releasing factor (CRF) is well known for its role in regulating the stress response in vertebrate species by controlling release of glucocorticoids. CRF also influences other physiological processes via two distinct CRF receptors (CRF-Rs) and is co-regulated by a CRF binding protein (CRFBP). Although CRF was first discovered in mammals, it is important for the regulation of the stress response, motor behavior, and appetite in all vertebrates. However, it is unclear how the actions of CRF, CRF-Rs, and CRFBP are coordinated. To approach this problem, we cloned and identified CRF, CRF-Rs, and CRFBP in a teleost fish model system, Astatotilapia burtoni and mapped their expression patterns in the body and brain. We found that CRF, CRFBP, and CRF-Rs gene sequences are highly conserved across vertebrates, suggesting that the CRF system plays an essential role in survival. Members of the CRF system are expressed widely in the brain, retina, gill, spleen, muscle, and kidney, thereby implicating them in a variety of bodily functions, including vision, respiration, digestion, and movement. We also found that following long-term social stress, mRNA expression of CRF in the brain and CRF type 1 receptor in the pituitary decrease whereas CRFBP in the pituitary increases via a homeostatic mechanism.
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Hormônio Liberador da Corticotropina/genética , Proteínas de Peixes/genética , Perfilação da Expressão Gênica , Perciformes/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/genética , Feminino , Masculino , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Hormônio Liberador da Corticotropina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de SequênciaRESUMO
Multiple GnRH receptors are known to exist in nonmammalian species, but it is uncertain which receptor type regulates reproduction via the hypothalamic-pituitary-gonadal axis. The teleost fish, Astatotilapia burtoni, is useful for identifying the GnRH receptor responsible for reproduction, because only territorial males reproduce. We have cloned a second GnRH receptor in A. burtoni, GnRH-R1(SHS) (SHS is a peptide motif in extracellular loop 3), which is up-regulated in pituitaries of territorial males. We have shown that GnRH-R1(SHS) is expressed in many tissues and specifically colocalizes with LH in the pituitary. In A. burtoni brain, mRNA levels of both GnRH-R1(SHS) and a previously identified receptor, GnRH-R2(PEY), are highly correlated with mRNA levels of all three GnRH ligands. Despite its likely role in reproduction, we found that GnRH-R1(SHS) has the highest affinity for GnRH2 in vitro and low responsivity to GnRH1. Our phylogenetic analysis shows that GnRH-R1(SHS) is less closely related to mammalian reproductive GnRH receptors than GnRH-R2(PEY). We correlated vertebrate GnRH receptor amino acid sequences with receptor function and tissue distribution in many species and found that GnRH receptor sequences predict ligand responsiveness but not colocalization with pituitary gonadotropes. Based on sequence analysis, tissue localization, and physiological response we propose that the GnRH-R1(SHS) receptor controls reproduction in teleosts, including A. burtoni. We propose a GnRH receptor classification based on gene sequence that correlates with ligand selectivity but not with reproductive control. Our results suggest that different duplicated GnRH receptor genes have been selected to regulate reproduction in different vertebrate lineages.
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Ciclídeos/metabolismo , Evolução Molecular , Receptores LHRH/química , Receptores LHRH/metabolismo , Receptores LHRH/fisiologia , Sequência de Aminoácidos , Animais , Ligação Competitiva , Encéfalo/metabolismo , Ritmo Circadiano , Clonagem Molecular , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Ligantes , Masculino , Filogenia , RNA Mensageiro/metabolismo , Receptores LHRH/genética , Reprodução/fisiologia , Distribuição TecidualRESUMO
Gonadotropin-releasing hormone 1 (GnRH1) from the brain controls reproduction in vertebrates via a GnRH-specific receptor in the pituitary; however, other forms of GnRH are found in all species, suggesting additional roles for this family of peptides. GnRH action depends critically on the location of its cognate receptors in the brain. To understand the potential roles of additional GnRH forms, we localized two known GnRH receptor types in a cichlid fish, Astatotilapia burtoni, in which GnRH1 is socially regulated. Using in situ hybridization, we describe the mRNA expression pattern of these GnRH receptor (GnRH-R) subtypes in the brain, specifically with respect to GnRH-producing neurons. Our data suggest that following a gene duplication, the two GnRH receptors have evolved to serve different functions. The type 1 receptor (GnRH-R1) is expressed less widely than the type 2 receptor (GnRH-R2). Specifically, GnRH-R1 is expressed in groups of neurons in the telencephalon, preoptic area, ventral hypothalamus, thalamus, and pituitary. In contrast, GnRH-R2 is expressed in many more brain areas, including the olfactory bulb, telencephalon, preoptic area, hypothalamus, thalamus, midbrain, optic tectum, cerebellum, hindbrain, and pituitary. The specific distribution of GnRH-R2 suggests that the GnRH ligands may act via this receptor to influence behavior in A. burtoni. Moreover, only GnRH-R2 mRNA is colocalized in the three known groups of GnRH-containing neurons, suggesting that any direct feedback regulation of GnRH by itself must act through this receptor type. Taken together, these data suggest that the two GnRH receptor types serve different functional roles in A. burtoni.
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Encéfalo/metabolismo , Ciclídeos/fisiologia , Receptores LHRH/biossíntese , Animais , Expressão Gênica , Perfilação da Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Hipófise/metabolismo , RNA Mensageiro/análiseRESUMO
Only a few distantly related mammals and birds have the trait of complex vocal learning, which is the ability to imitate novel sounds. This ability is critical for speech acquisition and production in humans, and is attributed to specialized forebrain vocal control circuits that have several unique connections relative to adjacent brain circuits. As a result, it has been hypothesized that there could exist convergent changes in genes involved in neural connectivity of vocal learning circuits. In support of this hypothesis, expanding on our related study (Pfenning et al. [2014] Science 346: 1256846), here we show that the forebrain part of this circuit that makes a relatively rare direct connection to brainstem vocal motor neurons in independent lineages of vocal learning birds (songbird, parrot, and hummingbird) has specialized regulation of axon guidance genes from the SLIT-ROBO molecular pathway. The SLIT1 ligand was differentially downregulated in the motor song output nucleus that makes the direct projection, whereas its receptor ROBO1 was developmentally upregulated during critical periods for vocal learning. Vocal nonlearning bird species and male mice, which have much more limited vocal plasticity and associated circuits, did not show comparable specialized regulation of SLIT-ROBO genes in their nonvocal motor cortical regions. These findings are consistent with SLIT and ROBO gene dysfunctions associated with autism, dyslexia, and speech sound language disorders and suggest that convergent evolution of vocal learning was associated with convergent changes in the SLIT-ROBO axon guidance pathway.
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Axônios/fisiologia , Encéfalo/anatomia & histologia , Regulação da Expressão Gênica/fisiologia , Glicoproteínas/metabolismo , Aprendizagem/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Vocalização Animal/fisiologia , Fatores Etários , Animais , Aves/fisiologia , Feminino , Glicoproteínas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , RNA Mensageiro/metabolismo , Receptores Imunológicos/genética , Proteínas RoundaboutRESUMO
Pluripotent stem cells have the potential to become any cell in the adult body, including neurons and glia. Avian stem cells could be used to study questions, like vocal learning, that would be difficult to examine with traditional mouse models. Induced pluripotent stem cells (iPSCs) are differentiated cells that have been reprogrammed to a pluripotent stem cell state, usually using inducing genes or other molecules. We recently succeeded in generating avian iPSC-like cells using mammalian genes, overcoming a limitation in the generation and use of iPSCs in nonmammalian species (Rosselló et al., 2013). However, there were no established optimal cell culture conditions for avian iPSCs to establish long-term cell lines and thus to study neuronal differentiation in vitro. Here we present an efficient method of maintaining chicken iPSC-like cells and for differentiating them into action potential generating neurons.
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Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system 'maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of 'reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well-annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross-species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution.
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Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Animais , Mapeamento Encefálico/normas , Evolução Química , Expressão Gênica/fisiologia , Humanos , Disseminação de Informação/métodos , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Especificidade da EspécieRESUMO
In our companion study (Jarvis et al. [2013] J Comp Neurol. doi: 10.1002/cne.23404) we used quantitative brain molecular profiling to discover that distinct subdivisions in the avian pallium above and below the ventricle and the associated mesopallium lamina have similar molecular profiles, leading to a hypothesis that they may form as continuous subdivisions around the lateral ventricle. To explore this hypothesis, here we profiled the expression of 16 genes at eight developmental stages. The genes included those that define brain subdivisions in the adult and some that are also involved in brain development. We found that phyletic hierarchical cluster and linear regression network analyses of gene expression profiles implicated single and mixed ancestry of these brain regions at early embryonic stages. Most gene expression-defined pallial subdivisions began as one ventral or dorsal domain that later formed specific folds around the lateral ventricle. Subsequently a clear ventricle boundary formed, partitioning them into dorsal and ventral pallial subdivisions surrounding the mesopallium lamina. These subdivisions each included two parts of the mesopallium, the nidopallium and hyperpallium, and the arcopallium and hippocampus, respectively. Each subdivision expression profile had a different temporal order of appearance, similar in timing to the order of analogous cell types of the mammalian cortex. Furthermore, like the mammalian pallium, expression in the ventral pallial subdivisions became distinct during prehatch development, whereas the dorsal portions did so during posthatch development. These findings support the continuum hypothesis of avian brain subdivision development around the ventricle and influence hypotheses on homologies of the avian pallium with other vertebrates.
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Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Expressão Gênica/fisiologia , Telencéfalo , Fatores Etários , Animais , Animais Recém-Nascidos , Contagem de Células , Embrião não Mamífero , Feminino , Redes Reguladoras de Genes/genética , Masculino , Aves Canoras , Telencéfalo/embriologia , Telencéfalo/crescimento & desenvolvimento , Telencéfalo/metabolismoRESUMO
This Review focuses on the development of metal aminoboranes; it discusses their synthesis, structure, chemical characterization, and applications. The lightweight nature of the molecules, the simplified procedures for the synthesis of the target compounds, the reversibility of hydrogen storage and dehydrogenation, and in-depth research on the mechanism of the thermal decomposition are also discussed. A major challenge that still remains is how to combine the advantages of the compounds to produce a material that is not only able to release and absorb hydrogen under atmospheric conditions, but is also lightweight with a stable molecular structure. Finally, some future trends and perspectives in these research areas will be outlined.
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Cells are fundamental units of life, but little is known about evolution of cell states. Induced pluripotent stem cells (iPSCs) are once differentiated cells that have been re-programmed to an embryonic stem cell-like state, providing a powerful platform for biology and medicine. However, they have been limited to a few mammalian species. Here we found that a set of four mammalian transcription factor genes used to generate iPSCs in mouse and humans can induce a partially reprogrammed pluripotent stem cell (PRPSCs) state in vertebrate and invertebrate model organisms, in mammals, birds, fish, and fly, which span 550 million years from a common ancestor. These findings are one of the first to show cross-lineage stem cell-like induction, and to generate pluripotent-like cells for several of these species with in vivo chimeras. We suggest that the stem-cell state may be highly conserved across a wide phylogenetic range. DOI:http://dx.doi.org/10.7554/eLife.00036.001.
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Reprogramação Celular , Células-Tronco Embrionárias/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Biomarcadores/metabolismo , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Embrião de Galinha , Quimera , Drosophila , Tentilhões , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Cariotipagem , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Codorniz , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Telomerase/metabolismo , Fatores de Transcrição/genética , Transfecção , Peixe-ZebraRESUMO
Based on quantitative cluster analyses of 52 constitutively expressed or behaviorally regulated genes in 23 brain regions, we present a global view of telencephalic organization of birds. The patterns of constitutively expressed genes revealed a partial mirror image organization of three major cell populations that wrap above, around, and below the ventricle and adjacent lamina through the mesopallium. The patterns of behaviorally regulated genes revealed functional columns of activation across boundaries of these cell populations, reminiscent of columns through layers of the mammalian cortex. The avian functionally regulated columns were of two types: those above the ventricle and associated mesopallial lamina, formed by our revised dorsal mesopallium, hyperpallium, and intercalated hyperpallium; and those below the ventricle, formed by our revised ventral mesopallium, nidopallium, and intercalated nidopallium. Based on these findings and known connectivity, we propose that the avian pallium has four major cell populations similar to those in mammalian cortex and some parts of the amygdala: 1) a primary sensory input population (intercalated pallium); 2) a secondary intrapallial population (nidopallium/hyperpallium); 3) a tertiary intrapallial population (mesopallium); and 4) a quaternary output population (the arcopallium). Each population contributes portions to columns that control different sensory or motor systems. We suggest that this organization of cell groups forms by expansion of contiguous developmental cell domains that wrap around the lateral ventricle and its extension through the middle of the mesopallium. We believe that the position of the lateral ventricle and its associated mesopallium lamina has resulted in a conceptual barrier to recognizing related cell groups across its border, thereby confounding our understanding of homologies with mammals.