A network of genes is recruited in developing oligodendrocytes to coordinate the production of myelin, a deficiency of which can drastically impair neuronal function in the central nervous system. Mechanisms operative in regulating myelin gene expression can be revealed by defining the set of transcription factors and signaling pathways that are selectively and temporally activated in developing oligodendrocytes. To examine the changing pattern of transcription factors and other genes selectively expressed by developing oligodendrocytes, we established a reliable microarray system combined with purification of oligodendrocytes by flow cytometry at different stages of differentiation. Such an approach has enabled the isolation and profiling of a novel, non-myelinating population of oligodendrocytes. The function and regulation of several genes expressed by this population of non-myelinating oligodendrocytes is being further examined in transgenic models to identify the molecular basis for the switch from a non-myelinating to a myelinating phenotype. Genetic profiling also revealed a family of semaphorin ligands and their cognate neuropilin receptors that influence the migration of oligodendrocyte progenitors (Cohen et al., 2003). Another signalling pathway involving the tyrosine protein phosphatase epsilon was implicated in axon-glial interactions in the optic nerve (Muja et al., in press). For the Myt1 myelin transcription factor, which modulates oligodendrocyte differentiation and proliferation (Nielsen et al., 2004), we defined an interaction with a transcriptional co-repressor, Sin3, that may locally modify chromatin structure to regulate myelin gene transcription. Combining transcriptomics with in vivo demyelinating paradigms, we have begun to evaluate the transcriptional response to myelin loss and the signaling that ensues between oligodendrocytes and their neuronal targets. These studies form the basis for devising strategies to promote remyelination in diseases such as multiple sclerosis, Pelizaeus-Merzbacher disease and spinal cord injury by stimulating endogenous oligodendrocyte progenitors to proliferate, migrate and myelinate.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Intramural Research (Z01)
Project #
1Z01NS002528-23
Application #
6989991
Study Section
(LDN)
Project Start
Project End
Budget Start
Budget End
Support Year
23
Fiscal Year
2004
Total Cost
Indirect Cost
City
State
Country
United States
Zip Code
Hudson, Lynn D; Romm, Elena; Berndt, Jo Ann et al. (2011) A tool for examining the role of the zinc finger myelin transcription factor 1 (Myt1) in neural development: Myt1 knock-in mice. Transgenic Res 20:951-61
Szuchet, Sara; Nielsen, Joseph A; Lovas, Gabor et al. (2011) The genetic signature of perineuronal oligodendrocytes reveals their unique phenotype. Eur J Neurosci 34:1906-22
Nielsen, Joseph A; Lau, Pierre; Maric, Dragan et al. (2009) Integrating microRNA and mRNA expression profiles of neuronal progenitors to identify regulatory networks underlying the onset of cortical neurogenesis. BMC Neurosci 10:98
Lau, Pierre; Verrier, Jonathan D; Nielsen, Joseph A et al. (2008) Identification of dynamically regulated microRNA and mRNA networks in developing oligodendrocytes. J Neurosci 28:11720-30
Nielsen, Joseph A; Maric, Dragan; Lau, Pierre et al. (2006) Identification of a novel oligodendrocyte cell adhesion protein using gene expression profiling. J Neurosci 26:9881-91
Kim, Hyunsook; Barton, Elisabeth; Muja, Naser et al. (2005) Intact insulin and insulin-like growth factor-I receptor signaling is required for growth hormone effects on skeletal muscle growth and function in vivo. Endocrinology 146:1772-9
Romm, Elena; Nielsen, Joseph A; Kim, Jin G et al. (2005) Myt1 family recruits histone deacetylase to regulate neural transcription. J Neurochem 93:1444-53
Muja, Naser; Lovas, Gabor; Romm, Elena et al. (2004) Expression of a catalytically inactive transmembrane protein tyrosine phosphatase epsilon (tm-PTP epsilon) delays optic nerve myelination. Glia 48:278-97
Nielsen, Joseph A; Berndt, Jo Ann; Hudson, Lynn D et al. (2004) Myelin transcription factor 1 (Myt1) modulates the proliferation and differentiation of oligodendrocyte lineage cells. Mol Cell Neurosci 25:111-23
Hudson, Lynn D (2003) Pelizaeus-Merzbacher disease and spastic paraplegia type 2: two faces of myelin loss from mutations in the same gene. J Child Neurol 18:616-24

Showing the most recent 10 out of 22 publications