Search results for " Neurogenesis"

Postnatal Neurogenesis and Neuronal Regeneration

2004

The discovery of neurogenesis in the adult brain has challenged one of the central dogmas of neuroscience. Pioneer reports in rodents seed the ground for a detailed description in birds and reptiles, which was finally confirmed in discrete regions of several mammalian species including humans. This neurogenetical capability may serve as the basis for neuronal regeneration, as has already been described in the reptilian brain, and thus may represent a promising therapeutic approach. Consequently, in the last years there has been an important effort to deepen our knowledge of the biology, the functional significance and the regulation of adult neurogenesis.

mTOR Driven Gene Transcription Is Required for Cholesterol Production in Neurons of the Developing Cerebral Cortex

2021

AbstractDysregulated mammalian target of rapamycin (mTOR) activity is associated with various neurodevelopmental disorders ranging from idiopathic autism spectrum disorders to syndromes caused by single gene defects. This suggests that maintaining mTOR activity levels in a physiological range is essential for brain development and functioning. Upon activation, mTOR regulates a variety of cellular processes such as cell growth, autophagy and metabolism. On a molecular level, however, the consequences of mTOR activation in the brain are not well understood.Low levels of cholesterol are associated with a wide variety of neurodevelopmental disorders. We here describe numerous genes of the stero…

Sea urchin neural alpha 2 tubulin gene: isolation and promoter analysis

2004

Abstract Expression of Tα2 gene, during sea urchin Paracentrotus lividus development, is spatially and temporally regulated. In order to characterize this gene, we isolated the relevant genomic sequences and scanned the isolated 5 ′ -flanking region in searching for cis -regulatory elements required for proper expression. Gel mobility shift and footprinting assays, as well as reporter gene (CAT and β-gal) expression assays, were used to address cis -regulatory elements involved in regulation. Here we report that an upstream 5 ′ -flanking fragment of PlTα2 gene drives temporal expression of reporter genes congruent with that of endogenous Tα2 gene. The fragment contains cis -elements able to…

A FOX Binding Site is Necessary for the Activation of Pl-Tuba1a Gene in the neurogenic domains

2016

All echinoderm larvae possess a nervous system consisting of a ciliary band and associated sensory ganglia (apical, oral and lateral ganglia) that controls swimming and feeding. Neurons of the larval nervous system first appear as neuroblasts in the thickened ectoderm of the animal plate (anterior neuroectoderm, ANE) at the late blastula – early gastrula stage and then also in the ciliary band. The neural differentiation process of sea urchin embryos has been analysed and the Gene Regulatory Network involved in the differentiation processes is extensively studied. We have previously isolated an alpha tubulin family member of the sea urchin Paracentrotus lividus (Pl-Tuba1a, formerly known as…

Social and sensory deficits in Rett syndrome: neuroanatomical and behavioural analyses in a mouse model deficient for mecp2

2023

El síndrome de Rett es una enfermedad rara del neurodesarrollo que afecta a 1 de cada 10.000 niñas en todo el mundo, y que supone la segunda causa de discapacidad intelectual de origen genético en mujeres. No existe una cura eficaz, y el tratamiento médico es meramente sintomatológico. Sin embargo, esta condición es mucho menos estudiada que otras enfermedades raras que afectan principalmente a niños. Se sabe que el síndrome de Rett está causado principalmente por mutaciones en el gen MECP2, que se localiza en el cromosoma X, haciendo que los niños mueran durante el primer año de vida y las niñas desarrollen la sintomatología característica de Rett a los 6-18 meses de edad. Entre los síntom…

Olfactory and cortical projections to bulbar and hippocampal adult-born neurons

2015

New neurons are continually generated in the subependymal layer of the lateral ventricles and the subgranular zone of dentate gyrus during adulthood. In the subventricular zone, neuroblasts migrate a long distance to the olfactory bulb where they differentiate into granule or periglomerular interneurons. In the hippocampus, neuroblasts migrate a short distance from the subgranular zone to the granule cell layer of the dentate gyrus to become granule neurons. In addition to the short-distance inputs, bulbar interneurons receive long-distance centrifugal afferents from olfactory-recipient structures. Similarly, dentate granule cells receive differential inputs from the medial and lateral ento…

Postnatal neurogenesis and regeneration in the lizard cerebral cortex

1993

Cocaine and MDMA Induce Cellular and Molecular Changes in Adult Neurogenic Systems: Functional Implications

2011

The capacity of the brain to generate new adult neurons is a recent discovery that challenges the old theory of an immutable adult brain. A new and fascinating field of research now focuses on this regenerative process. The two brain systems that constantly produce new adult neurons, known as the adult neurogenic systems, are the dentate gyrus (DG) of the hippocampus and the lateral ventricules/olfactory bulb system. Both systems are involved in memory and learning processes. Different drugs of abuse, such as cocaine and MDMA, have been shown to produce cellular and molecular changes that affect adult neurogenesis. This review summarizes the effects that these drugs have on the adult neurog…

Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.

2010

SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …

The lizard cerebral cortex as a model to study neuronal regeneration

2002

The medial cerebral cortex of lizards, an area homologous to the hippocampal fascia dentata, shows delayed postnatal neurogenesis, i.e., cells in the medial cortex ependyma proliferate and give rise to immature neurons, which migrate to the cell layer. There, recruited neurons differentiate and give rise to zinc containing axons directed to the rest of cortical areas, thus resulting in a continuous growth of the medial cortex and its zinc-enriched axonal projection. This happens along the lizard life span, even in adult lizards, thus allowing one of their most important characteristics: neuronal regeneration. Experiments in our laboratory have shown that chemical lesion of the medial cortex…