Retrotransposition Bursts in the Adult Brain: Stress, Running, and Instrumental Learning Increase the Number of L1 Retrotransposon DNA Copies in the Mouse Nervous System

NG2-glia, also called Oligodendrocyte Precursor Cells (OPCs), account for approximately 5%-10% of the cells in the developing and adult brain and constitute the fifth major cell population in the central nervous system. NG2-glia express receptors and ion channels involved in rapid modulation of neuronal activities and signaling with neuronal synapses, which have functional significance in both physiological and pathological states. NG2-glia participate in quick signaling with peripheral neurons via direct synaptic touches in the developing and mature central nervous system. These distinctive glia perform the unique function of proliferating and differentiating into oligodendrocytes in the early developing brain, which is critical for axon myelin formation. In response to injury, NG2-glia can proliferate, migrate to the lesions, and differentiate into oligodendrocytes to form new myelin sheaths, which wrap around damaged axons and result in functional recovery. The capacity of NG2-glia to regulate their behavior and dynamics in response to neuronal activity and disease indicate their critical role in myelin preservation and remodeling in the physiological state and in repair in the pathological state. In this review, we provide a detailed summary of the characteristics of NG2-glia, including their heterogeneity, the regulators of their proliferation, and the modulators of their differentiation into oligodendrocytes.

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The novel guanylyl cyclase MsGC-I is strongly expressed in higher-order neuropils in the brain of Manduca sexta

Journal of Experimental Biology ◽

10.1242/jeb.204.2.305 ◽

2001 ◽

Vol 204 (2) ◽

pp. 305-314 ◽

Cited By ~ 1

Author(s):

A. Nighorn ◽

P.J. Simpson ◽

D.B. Morton

Keyword(s):

Nervous System ◽

Manduca Sexta ◽

Guanylyl Cyclase ◽

Higher Order ◽

Adult Brain ◽

Central Complex ◽

Amino Acid Residues ◽

Order Processing ◽

Guanylyl Cyclases ◽

The Brain

Guanylyl cyclases are usually characterized as being either soluble (sGCs) or receptor (rGCs). We have recently cloned a novel guanylyl cyclase, MsGC-I, from the developing nervous system of the hawkmoth Manduca sexta that cannot be classified as either an sGC or an rGC. MsGC-I shows highest sequence identity with receptor guanylyl cyclases throughout its catalytic and dimerization domains, but does not contain the ligand-binding, transmembrane or kinase-like domains characteristic of receptor guanylyl cyclases. In addition, MsGC-I contains a C-terminal extension of 149 amino acid residues. In this paper, we report the expression of MsGC-I in the adult. Northern blots show that it is expressed preferentially in the nervous system, with high levels in the pharate adult brain and antennae. In the antennae, immunohistochemical analyses show that it is expressed in the cell bodies and dendrites, but not axons, of olfactory receptor neurons. In the brain, it is expressed in a variety of sensory neuropils including the antennal and optic lobes. It is also expressed in structures involved in higher-order processing including the mushroom bodies and central complex. This complicated expression pattern suggests that this novel guanylyl cyclase plays an important role in mediating cyclic GMP levels in the nervous system of Manduca sexta.

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Activity and expression pattern of cyclin-dependent kinase 5 in the embryonic mouse nervous system

Development ◽

10.1242/dev.119.4.1029 ◽

1993 ◽

Vol 119 (4) ◽

pp. 1029-1040 ◽

Cited By ~ 2

Author(s):

L.H. Tsai ◽

T. Takahashi ◽

V.S. Caviness ◽

E. Harlow

Keyword(s):

Nervous System ◽

Cell Division ◽

Cell Division Cycle ◽

Adult Brain ◽

Cyclin Dependent Kinase ◽

Proliferating Cells ◽

Embryonic Mouse ◽

Postmitotic Neurons ◽

Cyclin Dependent Kinase 5 ◽

Expression And Activity

Cyclin-dependent kinase 5 (cdk5) was originally isolated on the basis of its close primary sequence homology to the human cdc2 serine/threonine kinase, the prototype of the cyclin-dependent kinases. While kinase activities of both cdc2 and cdk2 are detected in proliferating cells and are essential for cells to progress through the key transition points of the cell cycle, cdk5 kinase activity has been observed only in lysates of adult brain. In this study, we compared the activity and expression of cdk5 with that of cdc2 and cdk2 in the embryonic mouse forebrain. The expression and activity of cdk5 increased progressively as increasing numbers of cells exited the proliferative cycle. In contrast, the expression and activity of cdc2 and cdk2 were maximum at gestational day 11 (E11) when the majority of cells were proliferating and fell to barely detectable levels at E17 at the end of the cytogenetic period. Immunohistochemical studies showed that cdk5 is expressed in postmitotic neurons but not in glial cells or mitotically active cells. Expression of cdk5 was concentrated in fasciculated axons of postmitotic neurons. In contrast to other cell division cycle kinases to which it is closely related, cdk5 appears not to be expressed in dividing cells in the developing brain. These observations suggest that cdk5 may have a role in neuronal differentiation but not in the cell division cycle in the embryonic nervous system.

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“Retrotransposition bursts” in the adult brain: Stress, running, and operant learning increase the number of L1 retrotransposon DNA copies in the mouse brain

IBRO Reports ◽

10.1016/j.ibror.2019.07.971 ◽

2019 ◽

Vol 6 ◽

pp. S314

Author(s):

Konstantin Anokhin ◽

Olga Ivashkina

Keyword(s):

Mouse Brain ◽

Adult Brain ◽

Operant Learning ◽

L1 Retrotransposon

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Neurodevelopment

New Oxford Textbook of Psychiatry ◽

10.1093/med/9780198713005.003.0011 ◽

2020 ◽

pp. 91-100

Author(s):

Karl Zilles ◽

Nicola Palomero-Gallagher

Keyword(s):

Spinal Cord ◽

Nervous System ◽

Neural Tube ◽

Neural Plate ◽

Adult Brain ◽

The Central Nervous System ◽

Specialized Region ◽

The Brain ◽

Rostral Part ◽

Human Nervous System

The pre- and post-natal development of the human nervous system is briefly described, with special emphasis on the brain, particularly the cerebral and cerebellar cortices. The central nervous system originates from a specialized region of the ectoderm—the neural plate—which develops into the neural tube. The rostral part of the neural tube forms the adult brain, whereas the caudal part (behind the fifth somite) differentiates into the spinal cord. The embryonic brain has three vesicular enlargements: the forebrain, the midbrain, and the hindbrain. The histogenesis of the spinal cord, hindbrain, cerebellum, and cerebral cortex, including myelination, is discussed. The chapter closes with a description of the development of the hemispheric shape and the formation of gyri.

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The Role of Mast Cells in Stroke

Cells ◽

10.3390/cells8050437 ◽

2019 ◽

Vol 8 (5) ◽

pp. 437 ◽

Cited By ~ 8

Author(s):

Edoardo Parrella ◽

Vanessa Porrini ◽

Marina Benarese ◽

Marina Pizzi

Keyword(s):

Central Nervous System ◽

Immune Response ◽

Nervous System ◽

Mast Cells ◽

Brain Edema ◽

Hemorrhagic Stroke ◽

Inflammatory Responses ◽

Adult Brain ◽

The Central Nervous System

Mast cells (MCs) are densely granulated perivascular resident cells of hematopoietic origin. Through the release of preformed mediators stored in their granules and newly synthesized molecules, they are able to initiate, modulate, and prolong the immune response upon activation. Their presence in the central nervous system (CNS) has been documented for more than a century. Over the years, MCs have been associated with various neuroinflammatory conditions of CNS, including stroke. They can exacerbate CNS damage in models of ischemic and hemorrhagic stroke by amplifying the inflammatory responses and promoting brain–blood barrier disruption, brain edema, extravasation, and hemorrhage. Here, we review the role of these peculiar cells in the pathophysiology of stroke, in both immature and adult brain. Further, we discuss the role of MCs as potential targets for the treatment of stroke and the compounds potentially active as MCs modulators.

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Localization of phosphotyrosine adaptor protein ShcD/SHC4 in the adult rat central nervous system

BMC Neuroscience ◽

10.1186/s12868-019-0541-5 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Hannah N. Robeson ◽

Hayley R. Lau ◽

Laura A. New ◽

Jasmin Lalonde ◽

John N. Armstrong ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Olfactory Bulb ◽

Adaptor Protein ◽

Cell Types ◽

Olfactory Nerve ◽

Adult Brain ◽

Specific Cell ◽

Adult Rat ◽

Fiber Tracts

Abstract Background Mammalian Shc (Src homology and collagen) proteins comprise a family of four phosphotyrosine adaptor molecules which exhibit varied spatiotemporal expression and signaling functions. ShcD is the most recently discovered homologue and it is highly expressed in the developing central nervous system (CNS) and adult brain. Presently however, its localization within specific cell types of mature neural structures has yet to be characterized. Results In the current study, we examine the expression profile of ShcD in the adult rat CNS using immunohistochemistry, and compare with those of the neuronally enriched ShcB and ShcC proteins. ShcD shows relatively widespread distribution in the adult brain and spinal cord, with prominent levels of staining throughout the olfactory bulb, as well as in sub-structures of the cerebellum and hippocampus, including the subgranular zone. Co-localization studies confirm the expression of ShcD in mature neurons and progenitor cells. ShcD immunoreactivity is primarily localized to axons and somata, consistent with the function of ShcD as a cytoplasmic adaptor. Regional differences in expression are observed among neural Shc proteins, with ShcC predominating in the hippocampus, cerebellum, and some fiber tracts. Interestingly, ShcD is uniquely expressed in the olfactory nerve layer and in glomeruli of the main olfactory bulb. Conclusions Together our findings suggest that ShcD may provide a distinct signaling contribution within the olfactory system, and that overlapping expression of ShcD with other Shc proteins may allow compensatory functions in the brain.

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IGF-1 Restores Visual Cortex Plasticity in Adult Life by Reducing Local GABA Levels

Neural Plasticity ◽

10.1155/2012/250421 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 22

Author(s):

José Fernando Maya-Vetencourt ◽

Laura Baroncelli ◽

Alessandro Viegi ◽

Ettore Tiraboschi ◽

Eero Castren ◽

...

Keyword(s):

Nervous System ◽

Visual Cortex ◽

Neural Plasticity ◽

Cortical Neurons ◽

Environmental Enrichment ◽

Adult Life ◽

Monocular Deprivation ◽

Adult Brain ◽

Environmental Stimulation ◽

The Central Nervous System

The central nervous system architecture is markedly modified by sensory experience during early life, but a decline of plasticity occurs with age. Recent studies have challenged this dogma providing evidence that both pharmacological treatments and paradigms based on the manipulation of environmental stimulation levels can be successfully employed as strategies for enhancing plasticity in the adult nervous system. Insulin-like growth factor 1 (IGF-1) is a peptide implicated in prenatal and postnatal phases of brain development such as neurogenesis, neuronal differentiation, synaptogenesis, and experience-dependent plasticity. Here, using the visual system as a paradigmatic model, we report that IGF-1 reactivates neural plasticity in the adult brain. Exogenous administration of IGF-1 in the adult visual cortex, indeed, restores the susceptibility of cortical neurons to monocular deprivation and promotes the recovery of normal visual functions in adult amblyopic animals. These effects were accompanied by a marked reduction of intracortical GABA levels. Moreover, we show that a transitory increase of IGF-1 expression is associated to the plasticity reinstatement induced by environmental enrichment (EE) and that blocking IGF-1 action by means of the IGF-1 receptor antagonist JB1 prevents EE effects on plasticity processes.

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Expression of the unique NCAM VASE exon is independently regulated in distinct tissues during development.

The Journal of Cell Biology ◽

10.1083/jcb.111.5.2089 ◽

1990 ◽

Vol 111 (5) ◽

pp. 2089-2096 ◽

Cited By ~ 76

Author(s):

S J Small ◽

R Akeson

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Alternative Splicing ◽

Significant Proportion ◽

Adult Brain ◽

Alternative Exon ◽

Rat Tissues ◽

Regulation Of Expression ◽

Specific Expression

During development of the rat central nervous system, neural cell adhesion molecule (NCAM) mRNAs containing in the extracellular domain a 30-bp alternative exon, here named VASE, replace RNAs that lack this exon. The presence of this alternative exon between previously described exons 7 and 8 changes the predicted loop structure of the derived polypeptide from one resembling an immunoglobulin constant region domain to one resembling an immunoglobulin variable domain. This change could have significant effects on NCAM polypeptide function and cell-cell interaction. In this report we test multiple rat tissues for the presence of additional alternative exons at this position and also examine the regulation of splicing of the previously described exon. To sensitively examine alternative splicing, polymerase chain reactions (PCRs) with primers flanking the exon 7/exon 8 alternative splicing site were performed. Four categories of RNA samples were tested for new exons: whole brain from embryonic day 11 to adult, specific brain regions dissected from adult brain, clonal lines of neural cells in vitro, and muscle cells and tissues cultured in vitro and obtained by dissection. Within the limits of the PCR methodology, no evidence for any alternative exon other than the previously identified VASE was obtained. The regulation of expression of this exon was found to be complex and tissue specific. Expression of the 30-bp exon in the heart and nervous system was found to be regulated independently; a significant proportion of embryonic day 15 heart NCAM mRNAs contain VASE while only a very small amount of day 15 nervous system mRNAs contain VASE. Some adult central nervous system regions, notably the olfactory bulb and the peripheral nervous system structures adrenal gland and dorsal root ganglia, express NCAM which contains very little VASE. VASE is undetectable in NCAM PCR products from the olfactory epithelium. Other nervous system regions express significant quantities of NCAM both with and without VASE. Clonal cell lines in culture generally expressed very little VASE. These results indicate that a single alternative exon, VASE, is found in NCAM immunoglobulin-like loop 4 and that distinct tissues and nervous system regions regulate expression of VASE independently both during development and in adult animals.

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Tissue-specific expression of the heat shock protein HSP27 during Drosophila melanogaster development.

The Journal of Cell Biology ◽

10.1083/jcb.111.3.817 ◽

1990 ◽

Vol 111 (3) ◽

pp. 817-828 ◽

Cited By ~ 78

Author(s):

D Pauli ◽

C H Tonka ◽

A Tissieres ◽

A P Arrigo

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Drosophila Melanogaster ◽

Heat Shock ◽

Stress Protein ◽

Pupal Stage ◽

Adult Brain ◽

Proliferating Cells ◽

Specific Expression ◽

The Central Nervous System

The alpha-crystallin-related heat shock (stress) protein hsp27 is expressed in absence of heat shock during Drosophila melanogaster development. Here, we describe the tissue distribution of this protein using an immunoaffinity-purified antibody. In embryos, hsp27 translated from maternal RNA is uniformly distributed, except in the yolk. During the first, second, and early third larval stages, hsp27 expression is restricted to the brain and the gonads. These tissues are characterized by a high level of proliferating cells. In late third instar larvae and early pupae, in addition to the central nervous system and the gonads, all the imaginal discs synthesize hsp27. The disc expression seems restricted to the beginning of their differentiation since it disappears during the second half of the pupal stage: no more hsp27 is observed in the disc-derived adult organs. In adults, hsp27 is still present in some regions of the central nervous system, and is also expressed in the male and female germ lines where it accumulates in mature sperm and oocytes. The transcript and the protein accumulate in oocytes since the onset of vitellogenesis with a uniform distribution similar to that found in embryos. The adult germ lines transcribe hsp27 gene while no transcript is detected in the late pupal and adult brain. These results suggest multiple roles of hsp27 during Drosophila development which may be related to both the proliferative and differentiated states of the tissues.

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