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Behavioural Brain Research Nov 2000Single, biocytin filled neurons in combination with immunocytochemistry and retrograde tracing as well as material with traditional double-immunolabeling were used at... (Review)
Review
Single, biocytin filled neurons in combination with immunocytochemistry and retrograde tracing as well as material with traditional double-immunolabeling were used at the light and electron microscopic levels to study the neural circuitry within the basal forebrain. Cholinergic neurons projecting to the frontal cortex exhibited extensive local collaterals terminating on non-cholinergic, (possible GABAergic) neurons within the basal forebrain. Elaborate axon arbors confined to the basal forebrain region also originated from NPY, somatostatin and other non-cholinergic interneurons. It is proposed that putative interneurons together with local collaterals from projection neurons contribute to regional integrative processing in the basal forebrain that may participate in more selective functions, such as attention and cortical plasticity.
Topics: Animals; Basal Ganglia; Humans; Neurons; Parasympathetic Nervous System; Parvalbumins; Prosencephalon; Synapses
PubMed: 11000417
DOI: 10.1016/s0166-4328(00)00255-2 -
Cellular and Molecular Life Sciences :... Jan 2014Chicken ovalbumin upstream promoter transcription factors (COUP-TFs) are nuclear receptors belonging to the superfamily of the steroid/thyroid hormone receptors. Members... (Review)
Review
Chicken ovalbumin upstream promoter transcription factors (COUP-TFs) are nuclear receptors belonging to the superfamily of the steroid/thyroid hormone receptors. Members of this family are internalized to the nucleus both in a ligand-dependent or -independent manner and act as strong transcriptional regulators by binding to the DNA of their target genes. COUP-TFs are defined as orphan receptors, since ligands regulating their activity have not so far been identified. From the very beginning of metazoan evolution, these molecules have been involved in various key events during embryonic development and organogenesis. In this review, we will mainly focus on their function during development and maturation of the central nervous system, which has been well characterized in various animal classes ranging from ctenophores to mammals. We will start by introducing the current knowledge on COUP-TF mechanisms of action and then focus our discussion on the crucial processes underlying forebrain ontogenesis, with special emphasis on mammalian development. Finally, the conserved roles of COUP-TFs along phylogenesis will be highlighted, and some hypotheses, worth exploring in future years to gain more insight into the mechanisms controlled by these factors, will be proposed.
Topics: Animals; COUP Transcription Factors; Cerebral Cortex; Hippocampus; Humans; Neurogenesis; Prosencephalon
PubMed: 23525662
DOI: 10.1007/s00018-013-1320-6 -
Trends in Neurosciences Sep 1996Neural precursor cells have been of interest historically as the building blocks of the embryonic CNS and, most recently, as substrates for restorative neurological... (Review)
Review
Neural precursor cells have been of interest historically as the building blocks of the embryonic CNS and, most recently, as substrates for restorative neurological approaches. The majority of previous in vitro studies of the regulation of neural-cell proliferation by polypeptide growth factors, and in vivo studies of neural lineage, argue for the presence of precursors with limited proliferative or lineage potential in the mammalian CNS. This is in contrast to renewable tissues, such as the blood or immune system, skin epithelium and epithelium of the small intestinal crypts, which contain specialized, self-renewing cells known as stem cells. However, recent in vitro and in vivo studies from our and other laboratories lead us to conclude that neural stem cells, with self-renewal and multilineage potential, are present in the embryonic through to adult mammalian forebrain.
Topics: Animals; Epidermal Growth Factor; Models, Biological; Prosencephalon; Stem Cells
PubMed: 8873356
DOI: 10.1016/s0166-2236(96)10035-7 -
Seminars in Cell & Developmental Biology Aug 2009
Topics: Animals; Humans; Prosencephalon; Vertebrates
PubMed: 19446031
DOI: 10.1016/j.semcdb.2009.05.001 -
Advances in Experimental Medicine and... 1991
Review
Topics: Animals; Brain; Humans; Prosencephalon
PubMed: 1776564
DOI: 10.1007/978-1-4757-0145-6_1 -
Current Opinion in Genetics &... Aug 2012In recent years, much progress has been made in understanding the process by which the brain is organised into specific regions. Much less is known about the way... (Review)
Review
In recent years, much progress has been made in understanding the process by which the brain is organised into specific regions. Much less is known about the way neuronal subtypes are defined inside these areas and how the temporal control of connectivity between neurons is achieved. Our thought processes and behaviours depend upon the development of neuronal circuits located in the most anterior brain area: the telencephalon (forming our cerebral cortex). The transcription factor Foxg1 is crucial to the development of specific neuronal fates inside this region and recent findings in zebrafish and mouse unveiled its impact as an integrator of telencephalic signalling centres. This essential regulatory activity may be key to understand Foxg1-dependent human disorders.
Topics: Animals; Cell Lineage; Forkhead Transcription Factors; Gene Expression Regulation, Developmental; Humans; Prosencephalon; Signal Transduction; Wnt Proteins
PubMed: 22742851
DOI: 10.1016/j.gde.2012.05.001 -
Current Opinion in Neurobiology Aug 2010Males and females exhibit numerous anatomical and physiological differences in the brain that often underlie important sex differences in physiology or behavior,... (Review)
Review
Males and females exhibit numerous anatomical and physiological differences in the brain that often underlie important sex differences in physiology or behavior, including aspects relating to reproduction. Neural sex differences are both region-specific and trait-specific and may consist of divergences in synapse morphology, neuron size and number, and specific gene expression levels. In most cases, sex differences are induced by the sex steroid hormonal milieu during early perinatal development. In rodents, the hypothalamic anteroventral periventricular nucleus (AVPV) is sexually differentiated as a result of postnatal sex steroids, and also specific neuronal populations in this nucleus are sexually dimorphic, with females possessing more kisspeptin, dopaminergic, and GABA/glutamate neurons than males. The ability of female rodents, but not males, to display an estrogen-induced luteinizing hormone (LH) surge is consistent with the higher levels of these neuropeptides in the AVPV of females. Of these AVPV populations, the recently identified kisspeptin system has been most strongly implicated as a crucial component of the sexually dimorphic LH surge mechanism, though GABA and glutamate have also received some attention. New findings have suggested that the sexual differentiation and development of kisspeptin neurons in the AVPV is mediated by developmental estradiol signaling. Although apoptosis is the most common process implicated in neuronal sexual differentiation, it is currently unknown how developmental estradiol acts to differentiate specific neuronal populations in the AVPV, such as kisspeptin or dopaminergic neurons.
Topics: Animals; Female; Male; Nerve Net; Neurons; Prosencephalon; Sex Differentiation; Steroids
PubMed: 20471241
DOI: 10.1016/j.conb.2010.04.004 -
Seminars in Cell & Developmental Biology Jun 2009Embryonic development of the mammalian forebrain is guided by signals from four patterning centers. The concerted actions of these signals transform the anterior neural... (Review)
Review
Embryonic development of the mammalian forebrain is guided by signals from four patterning centers. The concerted actions of these signals transform the anterior neural plate and prosencephalon into discrete forebrain structures including the telencephalon (cerebral cortex and basal ganglia) and hypothalamus. In this review, we describe the signaling, transcriptional, and regulatory events that lead to induction of the prospective telencephalon, and that instruct regional development of distinct telencephalic areas along the rostrocaudal and dorsoventral axes.
Topics: Animals; Body Patterning; Embryo, Mammalian; Embryonic Development; Prosencephalon; Signal Transduction
PubMed: 19560042
DOI: 10.1016/j.semcdb.2009.02.005 -
Neuroscience and Biobehavioral Reviews 2006The conceptual basis and continuing development of Alheid and Heimer's [Alheid, G.F., Heimer, L., 1988. New perspectives in basal forebrain organization of special... (Review)
Review
The conceptual basis and continuing development of Alheid and Heimer's [Alheid, G.F., Heimer, L., 1988. New perspectives in basal forebrain organization of special relevance for neuropsychiatric disorders: the striatopallidal, amygdaloid and corticopetal components of substantia innominata. Neuroscience 27, 1-39] theory of basal forebrain organization based on the description of basal forebrain functional-anatomical 'macrosytems' is reviewed. It is posed that the macrosystem theory leads to a hypothesis that different macrosystems cooperate and compete to exert distinct influences on motor and cognitive function. Emergent corollaries include, e.g. that the organization of the outputs of different macrosystems should differ. Consistent with these considerations, extant literature and some unpublished data indicate that the input nuclei of macrosystems are not abundantly interconnected and macrosystems systems have distinct neuroanatomical relationships with basal forebrain and brainstem cholinergic and dopaminergic ascending modulatory systems. Furthermore, macrosystem outputs appear to be directed almost exclusively at the reticular formation or structures intimately associated with it. The relative merits of the theory of functional-anatomical macrosystems are discussed in relation to Swanson's model of cerebral hemisphere control of motivated behavior.
Topics: Animals; Basal Ganglia; Humans; Limbic System; Neural Pathways; Prosencephalon
PubMed: 16125239
DOI: 10.1016/j.neubiorev.2005.06.003 -
Current Opinion in Neurobiology Apr 2009In the developing brain, the tangential mode of migration appears as an efficient strategy for newly generated neurons to reach destinations that are far away from their... (Review)
Review
In the developing brain, the tangential mode of migration appears as an efficient strategy for newly generated neurons to reach destinations that are far away from their site of origin, as opposed to local migration along radial glia process. The ganglionic eminence, in the vertebrate subpallium, is the main source of tangentially migrating neurons in the forebrain. However, little is known about the transcriptional control of such long-distance tangential migrations. Here, we review recent findings showing that homeodomain (HD) transcription factors (TFs) regulate the tangential migration of telencephalic neurons through the expression of several downstream targets including other TFs, axon guidance molecules, and cytoskeletal components. This molecular mechanism also seems to apply to tangentially migrating neurons in other parts of the brain.
Topics: Animals; Cell Movement; Cytoskeleton; Gene Expression Regulation, Developmental; Homeodomain Proteins; Humans; Interneurons; Neurons; Prosencephalon; Telencephalon; Transcription, Genetic
PubMed: 19428236
DOI: 10.1016/j.conb.2009.04.005