The Teratogenic effects of salicylic acid on the developing nervous system in rats in vitro

In the developing vertebrate nervous system the survival of neurons becomes dependent on the supply of a neurotrophic factor from their targets when their axons reach these targets. To determine how the onset of neurotrophic factor dependency is coordinated with the arrival of axons in the target field, we have studied the growth and survival of four populations of cranial sensory neurons whose axons have markedly different distances to grow to reach their targets. Axonal growth rate both in vivo and in vitro is related to target distance; neurons with more distant targets grow faster. The onset trophic factor dependency in culture is also related to target distance; neurons with more distant targets survive longer before becoming trophic factor dependent. These data suggest that programmes of growth and survival in early neurons play an important role in coordinating the timing of trophic interactions in the developing nervous system.

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A Critical Temporal Requirement for the Retinoblastoma Protein Family During Neuronal Determination

The Journal of Cell Biology ◽

10.1083/jcb.140.6.1497 ◽

1998 ◽

Vol 140 (6) ◽

pp. 1497-1509 ◽

Cited By ~ 66

Author(s):

Ruth S. Slack ◽

Hiba El-Bizri ◽

Josée Wong ◽

Daniel J. Belliveau ◽

Freda D. Miller

Keyword(s):

Cell Cycle ◽

Nervous System ◽

Cortical Neurons ◽

Adenovirus E1a ◽

Neuronal Gene ◽

Developing Neocortex ◽

Postmitotic Neurons ◽

Developing Nervous System

In this report, we have examined the requirement for the retinoblastoma (Rb) gene family in neuronal determination with a focus on the developing neocortex. To determine whether pRb is required for neuronal determination in vivo, we crossed the Rb−/− mice with transgenic mice expressing β-galactosidase from the early, panneuronal Tα1 α-tubulin promoter (Tα1:nlacZ). In E12.5 Rb−/− embryos, the Tα1:nlacZ transgene was robustly expressed throughout the developing nervous system. However, by E14.5, there were perturbations in Tα1:nlacZ expression throughout the nervous system, including deficits in the forebrain and retina. To more precisely define the temporal requirement for pRb in neuronal determination, we functionally ablated the pRb family in wild-type cortical progenitor cells that undergo the transition to postmitotic neurons in vitro by expression of a mutant adenovirus E1A protein. These studies revealed that induction of Tα1:nlacZ did not require proteins of the pRb family. However, in their absence, determined, Tα1:nlacZ-positive cortical neurons underwent apoptosis, presumably as a consequence of “mixed signals” deriving from their inability to undergo terminal mitosis. In contrast, when the pRb family was ablated in postmitotic cortical neurons, there was no effect on neuronal survival, nor did it cause the postmitotic neurons to reenter the cell cycle. Together, these studies define a critical temporal window of requirement for the pRb family; these proteins are not required for induction of neuronal gene expression or for the maintenance of postmitotic neurons, but are essential for determined neurons to exit the cell cycle and survive.

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Oligodendrocyte precursor (O-2A progenitor cell) migration; a model system for the study of cell migration in the developing central nervous system

Development ◽

10.1242/dev.119.supplement.219 ◽

1993 ◽

Vol 119 (Supplement) ◽

pp. 219-225 ◽

Cited By ~ 2

Author(s):

B. W. Kiernan ◽

Charles ffrench-Constant

Keyword(s):

Nervous System ◽

Cell Migration ◽

Progenitor Cell ◽

Molecular Mechanisms ◽

Cultured Cells ◽

Large Numbers ◽

Multicellular Organisms ◽

Developing Nervous System

Cell migration plays an important role in the development of complex multicellular organisms. The molecular mechanisms that regulate this migration arc therefore of great interest. Unfortunately, however, analysis of cell migration in vertebrates is hampered by the inaccessability of the cells and the difficulty of manipulating their environment within the embryo. This review focusses on one particular migratory cell population, the oligodendrocyte p1ecursor cell or O-2A progenitor cell, that gives rise to the myelin-forming oligodendrocytes within the CNS. These cells mi grate extensively during normal development. They can be purified and grown in large numbers in cell culture, so allowing the use of reductionist approaches using cell and molecular biology techniques. Moreover, cultured cells will migrate within the CNS following transplantation. As a result, the migration of these cells in vivo can be analysed following manipulation in vitro. Taken together, we believe that the different properties of these cells makes them excellent candidates for studies addressing the control of cell migration in the developing nervous system.

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Identification of MoKA, a Novel F-Box Protein That Modulates Krüppel-Like Transcription Factor 7 Activity

Molecular and Cellular Biology ◽

10.1128/mcb.24.3.1058-1069.2004 ◽

2004 ◽

Vol 24 (3) ◽

pp. 1058-1069 ◽

Cited By ~ 29

Author(s):

Silvia Smaldone ◽

Friedrich Laub ◽

Cindy Else ◽

Cecilia Dragomir ◽

Francesco Ramirez

Keyword(s):

Cell Cycle ◽

Nervous System ◽

Transcription Factor ◽

Mammalian Cells ◽

Cell Cycle Progression ◽

Direct Interaction ◽

Proximal Promoter ◽

F Box Protein ◽

Developing Nervous System

ABSTRACT KLF7, a member of the Krüppel-like transcription factor family, is believed to regulate neurogenesis and cell cycle progression. Here, a yeast two-hybrid screen for KLF7 cofactors in the developing nervous system identified a novel 140-kDa protein named MoKA, for modulator of KLF7 activity. Interaction between MoKA and KLF7 was confirmed by the in vitro glutathione S-transferase pull-down assay and by coimmunoprecipitation of the proteins overexpressed in mammalian cells. Functional assays documented that MoKA is a KLF7 coactivator, and in situ hybridizations identified the developing nervous system and the adult testes as two sites of MoKA and Klf7 coexpression. Chromatin immunoprecipitation experiments demonstrated KLF7 binding to the p21WAF1/Cip1 gene while transient transfection assays documented KLF7 stimulation of the p21WAF1/Cip1 proximal promoter. Additional tests revealed that distinct structural motifs of MoKA direct interaction with KLF7 and shuttling between the nucleus and cytoplasm of asynchronously cycling cells. Altogether, our results strongly suggest that MoKA and KLF7 interact functionally to regulate gene expression during cell differentiation and identify the cell cycle regulator p21WAF1/Cip1 as one of the targeted genes.

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A HISTOCHEMICAL AND BIOCHEMICAL STUDY OF THE POLYSACCHARIDIC SUBSTANCES OF THE DEVELOPING NERVOUS SYSTEM OF THE RAT IN RELATION WITH THE APPEARANCE OF CHOLINESTERASE ACTIVITY

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y58-032 ◽

1958 ◽

Vol 36 (1) ◽

pp. 275-288 ◽

Cited By ~ 1

Author(s):

Marc Crevier

Keyword(s):

Nervous System ◽

Acid Hydrolysis ◽

Biochemical Study ◽

Chemical Fractionation ◽

High Concentration ◽

Brain Substance ◽

Pas Reaction ◽

Irregular Action ◽

Developing Nervous System

The PAS reaction and the cholinesterase reaction run parallel in the lower centers of the developing nervous system in the rat. Also, the two reactions appear progressively between the 10th and 15th day as the result of a chemical maturation of the neurons. Extraction of sections with methanol–chloroform does not alter the PAS reaction while acetylation inhibits it reversibly. These two facts suggest that 1,2-glycol groups are detected. Inhibition by hyaluronidase increases this evidence, despite the fact that diastase has a slight and irregular action. To elucidate the nature of the PAS reaction further, chemical fractionation of the brain substance has been attempted. (A) A fraction soluble in methanol–chloroform is metachromatic and PAS-positive in vitro. (B) A fraction soluble in a potassium chloride – potassium carbonate mixture is non-dialyzable, non-metachromatic, but PAS-positive. After acid hydrolysis it yields glucose but no hexosamine. (C) A fraction extracted from the residue by sodium hydroxide is non-dialyzable, non-metachromatic, but also PAS-positive. By chromatography and electrophoresis it is found to contain a non-sulphated mucoprotein yielding hexosamine in a high concentration following acid hydrolysis. The physiological significance of this mucoprotein is discussed.

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Chicken Acidic Leucine-rich EGF-like Domain Containing Brain Protein (CALEB), a Neural Member of the EGF Family of Differentiation Factors, Is Implicated in Neurite Formation

The Journal of Cell Biology ◽

10.1083/jcb.136.4.895 ◽

1997 ◽

Vol 136 (4) ◽

pp. 895-906 ◽

Cited By ~ 37

Author(s):

Stefan Schumacher ◽

Hansjürgen Volkmer ◽

Fritz Buck ◽

Albrecht Otto ◽

Attila Tárnok ◽

...

Keyword(s):

Nervous System ◽

Brain Protein ◽

Binding Assays ◽

Multidomain Protein ◽

Differentiation Factors ◽

Neurite Formation ◽

Embryonic Nervous System ◽

Egf Family ◽

Developing Nervous System

Chicken acidic leucine-rich EGF-like domain containing brain protein (CALEB) was identified by combining binding assays with immunological screens in the chicken nervous system as a novel member of the EGF family of differentiation factors. cDNA cloning indicates that CALEB is a multidomain protein that consists of an NH2-terminal glycosylation region, a leucine-proline–rich segment, an acidic box, a single EGF-like domain, a transmembrane, and a short cytoplasmic stretch. In the developing nervous system, CALEB is associated with glial and neuronal surfaces. CALEB is composed of a 140/130-kD doublet, an 80-kD band, and a chondroitinsulfate-containing 200-kD component. The latter two components are expressed in the embryonic nervous system and are downregulated in the adult nervous system. CALEB binds to the extracellular matrix glycoproteins tenascin-C and -R. In vitro antibody perturbation experiments reveal a participation of CALEB in neurite formation in a permissive environment.

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A HISTOCHEMICAL AND BIOCHEMICAL STUDY OF THE POLYSACCHARIDIC SUBSTANCES OF THE DEVELOPING NERVOUS SYSTEM OF THE RAT IN RELATION WITH THE APPEARANCE OF CHOLINESTERASE ACTIVITY

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o58-032 ◽

1958 ◽

Vol 36 (3) ◽

pp. 275-288 ◽

Cited By ~ 5

Author(s):

Marc Crevier

Keyword(s):

Nervous System ◽

Acid Hydrolysis ◽

Biochemical Study ◽

Chemical Fractionation ◽

High Concentration ◽

Brain Substance ◽

Pas Reaction ◽

Irregular Action ◽

Developing Nervous System

The PAS reaction and the cholinesterase reaction run parallel in the lower centers of the developing nervous system in the rat. Also, the two reactions appear progressively between the 10th and 15th day as the result of a chemical maturation of the neurons. Extraction of sections with methanol–chloroform does not alter the PAS reaction while acetylation inhibits it reversibly. These two facts suggest that 1,2-glycol groups are detected. Inhibition by hyaluronidase increases this evidence, despite the fact that diastase has a slight and irregular action. To elucidate the nature of the PAS reaction further, chemical fractionation of the brain substance has been attempted. (A) A fraction soluble in methanol–chloroform is metachromatic and PAS-positive in vitro. (B) A fraction soluble in a potassium chloride – potassium carbonate mixture is non-dialyzable, non-metachromatic, but PAS-positive. After acid hydrolysis it yields glucose but no hexosamine. (C) A fraction extracted from the residue by sodium hydroxide is non-dialyzable, non-metachromatic, but also PAS-positive. By chromatography and electrophoresis it is found to contain a non-sulphated mucoprotein yielding hexosamine in a high concentration following acid hydrolysis. The physiological significance of this mucoprotein is discussed.

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Influence of salicylic acid on organogenesis of in vitro plants Fragaria ananassa Duch.

Fiziologia rastenij i genetika ◽

10.15407/frg2016.01.026 ◽

2016 ◽

Vol 48 (1) ◽

pp. 26-33

Author(s):

O.V. Subin ◽

◽

M.D. Melnychuk ◽

A.F. Likhanov ◽

O.L. Klyachenko ◽

...

Keyword(s):

Salicylic Acid ◽

Fragaria Ananassa ◽

In Vitro Plants

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Neural Stem Cells to Glial Cells an Important Factor for Brain Injury

Journal of Regenerative Biology and Medicine ◽

10.37191/mapsci-2582-385x-2(3)-025 ◽

2020 ◽

Author(s):

Prithiv K R Kumar

Keyword(s):

Stem Cells ◽

Central Nervous System ◽

Nervous System ◽

Neural Stem Cells ◽

Glial Cells ◽

Brain Injuries ◽

The Body ◽

The Central Nervous System ◽

Near Future

Stem cells have the capacity to differentiate into any type of cell or organ. Stems cell originate from any part of the body, including the brain. Brain cells or rather neural stem cells have the capacitive advantage of differentiating into the central nervous system leading to the formation of neurons and glial cells. Neural stem cells should have a source by editing DNA, or by mixings chemical enzymes of iPSCs. By this method, a limitless number of neuron stem cells can be obtained. Increase in supply of NSCs help in repairing glial cells which in-turn heal the central nervous system. Generally, brain injuries cause motor and sensory deficits leading to stroke. With all trials from novel therapeutic methods to enhanced rehabilitation time, the economy and quality of life is suppressed. Only PSCs have proven effective for grafting cells into NSCs. Neurons derived from stem cells is the only challenge that limits in-vitro usage in the near future.

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