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Mouse Central Nervous System (mouse + central_nervous_system)
Selected AbstractsRegional expression of MTG genes in the developing mouse central nervous systemDEVELOPMENTAL DYNAMICS, Issue 8 2009Amin Alishahi Abstract Myeloid translocation gene (MTG) proteins are transcriptional repressors that are highly conserved across species. We studied the expression of three members of this gene family, MTGR1, MTG8, and MTG16 in developing mouse central nervous system by in situ hybridization. All of these genes are detected as early as embryonic day 11.5. Because these genes are known to be induced by proneural genes during neurogenesis, we analyzed the expression of MTG genes in relation to two proneural genes, Neurog2 (also known as Ngn2 or Neurogenin 2) and Ascl1 (also known as Mash1). While MTGR1 are generally expressed in regions that also express Neurog2, MTG8 and MTG16 expression is associated more tightly with that of Ascl1 -expressing neural progenitor cells. These results suggest the possibility that expression of MTG genes is differentially controlled by specific proneural genes during neurogenesis. Developmental Dynamics 238:2095,2102, 2009. © 2009 Wiley-Liss, Inc. [source] Dynamic expression of de novo DNA methyltransferases Dnmt3a and Dnmt3b in the central nervous systemJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2005Jian Feng Abstract To explore the role of DNA methylation in the brain, we examined the expression pattern of de novo DNA methyltransferases Dnmt3a and Dnmt3b in the mouse central nervous system (CNS). By comparing the levels of Dnmt3a and Dnmt3b mRNAs and proteins in the CNS, we showed that Dnmt3b is detected within a narrow window during early neurogenesis, whereas Dnmt3a is present in both embryonic and postnatal CNS tissues. To determine the precise pattern of Dnmt3a and Dnmt3b gene expression, we carried out X-gal histochemistry in transgenic mice in which the lacZ marker gene is knocked into the endogenous Dnmt3a or Dnmt3b gene locus (Okano et al. [1999] Cell 99:247,257). In Dnmt3b - lacZ transgenic mice, X-gal-positive cells are dispersed across the ventricular zone of the CNS between embryonic days (E) 10.5 and 13.5 but become virtually undetectable in the CNS after E15.5. In Dnmt3a - lacZ mice, X-gal signal is initially observed primarily in neural precursor cells within the ventricular and subventricular zones between E10.5 and E17.5. However, from the newborn stage to adulthood, Dnmt3a X-gal signal was detected predominantly in postmitotic CNS neurons across all the regions examined, including olfactory bulb, cortex, hippocampus, striatum, and cerebellum. Furthermore, Dnmt3a signals in CNS neurons increase during the first 3 weeks of postnatal development and then decline to a relatively low level in adulthood, suggesting that Dnmt3a may be of critical importance for CNS maturation. Immunocytochemistry experiments confirmed that Dnmt3a protein is strongly expressed in neural precursor cells, postmitotic CNS neurons, and oligodendrocytes. In contrast, glial fibrillary acidic protein-positive astrocytes exhibit relatively weak or no Dnmt3a immunoreactivity in vitro and in vivo. Our data suggest that whereas Dnmt3b may be important for the early phase of neurogenesis, Dnmt3a likely plays a dual role in regulating neurogenesis prenatally and CNS maturation and function postnatally. © 2005 Wiley-Liss, Inc. [source] Complementary DNA cloning and characterization of RANDAM-2, a type I membrane molecule specifically expressed on glutamatergic neuronal cells in the mouse cerebrumJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2003Masaharu Kotani Abstract A membrane-surface glycoprotein, RANDAM-2, is one of the neuronal cell lineage-specific antigens involved in the neuronal differentiation of P19 embryonic carcinoma (EC) cells and the mouse central nervous system (CNS). Complementary DNA cloning of RANDAM-2 indicated that its nucleotide sequence completely matched that of PA2.26 antigen, a sialomucin-like transmembrane glycoprotein previously found on tumorigenic keratinocytes. RANDAM-2 transcripts were detectable from the embryonic stage of 6.5 days, and then the expression continued throughout the remaining embryonic stages and adulthood, with a localization restricted to the CNS. In growth factor-induced neurospheres and adult cerebrum, RANDAM-2-expressing cells coincided well not only with nestin-positive cells but also with glutamate-positive neurons, but not with ,-aminobutyric acid-positive ones. These results indicate that RANDAM-2 is one of the type I membrane surface antigens constitutively expressed on undifferentiated neuronal cells and the glutamatergic neuronal cells during mouse neurogenesis. © 2003 Wiley-Liss, Inc. [source] Peripheral somatosensory fMRI in mouse at 11.7 TNMR IN BIOMEDICINE, Issue 5 2001Eric T. Ahrens Abstract The feasibility of performing extremely-high resolution somatosensory fMRI in anesthetized mice using BOLD contrast at 11.7,T was investigated. A somatosensory stimulus was applied to the hindlimb of an ,-chlorolose anesthetized mouse resulting in robust (p,<,4,×,10,3) BOLD changes in somatosensory cortex and large veins. Percentage modulation of the MR signal in cortex exceeded 7%. Experiments that artificially modulated the inspired oxygen tension were also conducted; the results revealed large, heterogeneous, BOLD contrast changes in the mouse brain. In addition, T1, T2, and T2* values in gray matter at 11.7,T were evaluated. Discussion of the sensitivity limitations of BOLD fMRI in the tiny mouse central nervous system is presented. These methods show promise for the assessment of neurological function in mouse models of CNS injury and disease. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||