Search results for " Regulation"
showing 10 items of 3187 documents
Spatio-temporal expression of Prospero is finely tuned to allow the correct development and function of the nervous system in Drosophila melanogaster.
2007
0012-1606 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; Adaptive animal behaviors depend upon the precise development of the nervous system that underlies them. In Drosophila melanogaster, the pan-neural prospero gene (pros), is involved in various aspects of neurogenesis including cell cycle control, axonal outgrowth, neuronal and glial cell differentiation. As these results have been generally obtained with null pros mutants inducing embryonic lethality, the role of pros during later development remains poorly known. Using several pros-Voila (prosV) alleles, that induce multiple developmental and behavioral anomalies in the larva and in adult, we explored the…
Ems and Nkx6 are central regulators in dorsoventral patterning of the Drosophila brain
2009
In central nervous system development, the identity of neural stem cells (neuroblasts) critically depends on the precise spatial patterning of the neuroectoderm in the dorsoventral (DV) axis. Here, we uncover a novel gene regulatory network underlying DV patterning in the Drosophila brain, and show that the cephalic gap gene empty spiracles (ems) and the Nk6 homeobox gene (Nkx6) encode key regulators. The regulatory network implicates novel interactions between these and the evolutionarily conserved homeobox genes ventral nervous system defective (vnd), intermediate neuroblasts defective (ind) and muscle segment homeobox (msh). We show that Msh cross-repressively interacts with Nkx6 to sust…
Thyroid hormones and the central nervous system of mammals (Review)
2008
Abstract. The thyroid hormones (THs) L-thyroxine (T4) and L-triiodothyronine (T3) have a profound influence on the development and maturation of the mammalian brain, both before and after birth. Any impairment in the supply of THs to the developing nervous system leads to severe and irreversible changes in both the overall architecture and functions of the brain and causes, in humans, neurological and motor deficits known as cretinism. Pronounced neurological symptoms are also commonly observed in adult patients suffering from both hyperthyroidism and hypothyroidism, and it has recently emerged that certain symptoms might result from the reduced brain uptake, rather than the insufficient pr…
Dscam1 Is Required for Normal Dendrite Growth and Branching But Not for Dendritic Spacing in Drosophila Motoneurons
2014
Down syndrome cell adhesion molecule, Dscam, serves diverse neurodevelopmental functions, including axon guidance and synaptic adhesion, as well as self-recognition and self-avoidance, depending on the neuron type, brain region, or species under investigation. InDrosophila, the extensive molecular diversity that results from alternative splicing of Dscam1 into >38,000 isoforms provides neurons with a unique molecular code for self-recognition in the nervous system. Each neuron produces only a small subset of Dscam1 isoforms, and distinct Dscam1 isoforms mediate homophilic interactions, which in turn, result in repulsion and even spacing of self-processes, while allowing contact with neig…
The columnar gene vnd is required for tritocerebral neuromere formation during embryonic brain development of Drosophila.
2006
International audience; In Drosophila, evolutionarily conserved transcription factors are required for the specification of neural lineages along the anteroposterior and dorsoventral axes, such as Hox genes for anteroposterior and columnar genes for dorsoventral patterning. In this report, we analyse the role of the columnar patterning gene ventral nervous system defective (vnd) in embryonic brain development. Expression of vnd is observed in specific subsets of cells in all brain neuromeres. Loss-of-function analysis focussed on the tritocerebrum shows that inactivation of vnd results in regionalized axonal patterning defects, which are comparable with the brain phenotype caused by mutatio…
Characterization of molecular mechanisms underlying the axonal Charcot–Marie–Tooth neuropathy caused by MORC2 mutations
2019
Mutations in MORC2 lead to an axonal form of Charcot-Marie-Tooth (CMT) neuropathy type 2Z. To date, 31 families have been described with mutations in MORC2, indicating that this gene is frequently involved in axonal CMT cases. While the genetic data clearly establish the causative role of MORC2 in CMT2Z, the impact of its mutations on neuronal biology and their phenotypic consequences in patients remains to be clarified. We show that the full-length form of MORC2 is highly expressed in both embryonic and adult human neural tissues and that Morc2 expression is dynamically regulated in both the developing and the maturing murine nervous system. To determine the effect of the most common MORC2…
Glial precursors clear sensory neuron corpses during development via Jedi-1, an engulfment receptor
2009
During the development of peripheral ganglia, 50% of the neurons that are generated undergo apoptosis. How the massive numbers of corpses are removed is unknown. We found that satellite glial cell precursors are the primary phagocytic cells for apoptotic corpse removal in developing mouse dorsal root ganglia (DRG). Confocal and electron microscopic analysis revealed that glial precursors, rather than macrophages, were responsible for clearing most of the dead DRG neurons. Moreover, we identified Jedi-1, an engulfment receptor, and MEGF10, a purported engulfment receptor, as homologs of the invertebrate engulfment receptors Draper and CED-1 expressed in the glial precursor cells. Expression …
NG2-expressing cells in the nervous system revealed by the NG2-EYFP-knockin mouse.
2008
The NG2 glycoprotein is a type I membrane protein expressed by immature cells in the developing and adult mouse. NG2+ cells of the embryonic and adult brain have been principally viewed as oligodendrocyte precursor cells but have additionally been considered a fourth glial class. They are likely to be a heterogeneous population. In order to facilitate studies on the function of NG2+ cells and to characterize these cells in situ, we generated an enhanced yellow fluorescent protein (EYFP) “knockin mouse.” EYFP-expressing cells in heterozygous knockin mice expressed the NG2 protein in all regions and at all ages studied. The EYFP+ cells did not express markers of mature glia, developing or mat…
Segment-specific requirements for dorsoventral patterning genes during early brain development in Drosophila.
2006
An initial step in the development of the Drosophila central nervous system is the delamination of a stereotype population of neural stem cells (neuroblasts, NBs) from the neuroectoderm. Expression of the columnar genes ventral nervous system defective (vnd), intermediate neuroblasts defective (ind) and muscle segment homeobox (msh) subdivides the truncal neuroectoderm(primordium of the ventral nerve cord) into a ventral, intermediate and dorsal longitudinal domain, and has been shown to play a key role in the formation and/or specification of corresponding NBs. In the procephalic neuroectoderm(pNE, primordium of the brain), expression of columnar genes is highly complex and dynamic, and th…
Expression analysis of jagged genes in zebrafish embryos
2005
The interaction of transmembrane Delta and Jagged/Serrate ligands with Notch receptors on neighboring cells is critically involved in cell specification during development. In zebrafish, the early expression of delta but not of jagged genes has been investigated in some detail. We have analyzed the sequence and embryonic expression pattern of the three zebrafish genes jagged1a, jagged1b, and jagged2. These genes, whose transcripts are detectable by in situ hybridization from early somitogenesis, are widely and dynamically expressed in embryos. Coexpression is limited, however, to the notochord and lens (jagged1a and jagged1b) and to the otic vesicle and pronephros (jagged1b and jagged2). Co…