Patricia Wight | University of Arkansas for Medical Sciences (original) (raw)

Papers by Patricia Wight

Research paper thumbnail of Plp1 in the enteric nervous system is preferentially expressed during early postnatal development in mouse as DM20, whose expression appears reliant on an intronic enhancer

Frontiers in Cellular Neuroscience

Recently, the myelin proteolipid protein gene (Plp1) was shown to be expressed in the glia of the... more Recently, the myelin proteolipid protein gene (Plp1) was shown to be expressed in the glia of the enteric nervous system (ENS) in mouse. However, beyond this, not much is known about its expression in the intestine. To address this matter, we investigated Plp1 expression at the mRNA and protein levels in the intestine of mice at different ages (postnatal days 2, 9, 21, and 88). In this study, we show that Plp1 expression preferentially occurs during early postnatal development, primarily as the DM20 isoform. Western blot analysis indicated that DM20 migrated according to its formula weight when isolated from the intestine. However, mobilities of both PLP and DM20 were faster than expected when procured from the brain. The 6.2hPLP(+)Z/FL transgene, which uses the first half of the human PLP1 gene to drive expression of a lacZ reporter gene, recapitulated the developmental pattern observed with the native gene in the intestine, indicating that it can be used as a proxy for Plp1 gene e...

Research paper thumbnail of PLP1-lacZ transgenic mice reveal that splice variants containing “human-specific” exons are relatively minor in comparison to the archetypal transcript and that an upstream regulatory element bolsters expression during early postnatal brain development

Frontiers in Cellular Neuroscience

Much of what is known about the mechanisms that control the developmental expression of the myeli... more Much of what is known about the mechanisms that control the developmental expression of the myelin proteolipid protein gene (PLP1) has been attained through use of transgenic animal models. In this study, we analyzed expression of related transgenes which utilize PLP1 genomic DNA from either human or mouse to drive expression of a lacZ reporter. Human PLP1 (hPLP1) sequence span either the proximal 6.2 or 2.7 kb of 5′-flanking DNA to an internal site in Exon 2, while those from mouse comprise the proximal 2.3 kb of 5′-flanking DNA to an analogous site in Exon 2. Transgenes with hPLP1 sequence were named, in part, to the amount of upstream sequence they have [6.2hPLP(+)Z/FL and 2.7hPLP(+)Z]. The transgene containing mouse sequence is referred to here as mPLP(+)Z, to denote the species origin of PLP1 DNA. Mice which harbor the 6.2hPLP(+)Z/FL transgene were used as a model system to investigate the developmental expression of splice variants that incorporate supplementary exons from wha...

Research paper thumbnail of Please Note Change in Location

AGENDA 1) Announcements 2) Minutes of the previous meeting and business arising from the minutes ... more AGENDA 1) Announcements 2) Minutes of the previous meeting and business arising from the minutes 3) Question period

Research paper thumbnail of Expression of a Myelin Proteolipid Protein (Plp)-lacZ Transgene is Reduced in both the CNS and PNS of Plp jp Mice

Neurochemical Research, 2006

Jimpy (Plp jp ) is an X-linked recessive mutation in mice that causes CNS dysmyelination and earl... more Jimpy (Plp jp ) is an X-linked recessive mutation in mice that causes CNS dysmyelination and early death in affected males. It results from a point mutation in the acceptor splice site of myelin proteolipid protein (Plp) exon 5, producing transcripts that are missing exon 5, with a concomitant shift in the downstream reading frame. Expression of the mutant PLP product in Plp jp males leads to hypomyelination and oligodendrocyte death. Expression of our Plp-lacZ fusion gene, PLP(+)Z, in transgenic mice is an excellent readout for endogenous Plp transcriptional activity. The current studies assess expression of the PLP(+)Z transgene in the Plp jp background. These studies demonstrate that expression of the transgene is decreased in both the central and peripheral nervous systems of affected Plp jp males. Thus, expression of mutated PLP protein downregulates Plp gene activity both in oligodendrocytes, which eventually die, and in Schwann cells, which are apparently unaffected in Plp jp mice.

Research paper thumbnail of Effects of Intron 1 Sequences on Human PLP1 Expression: Implications for PLP1-Related Disorders

ASN Neuro, Jul 24, 2017

Alterations in the myelin proteolipid protein gene (PLP1) may result in rare X-linked disorders i... more Alterations in the myelin proteolipid protein gene (PLP1) may result in rare X-linked disorders in humans such as Pelizaeus-Merzbacher disease and spastic paraplegia type 2. PLP1 expression must be tightly regulated since null mutations, as well as elevated PLP1 copy number, both lead to disease. Previous studies with Plp1-lacZ transgenic mice have demonstrated that mouse Plp1 (mPlp1) intron 1 DNA (which accounts for slightly more than half of the gene) is required for the mPlp1 promoter to drive significant levels of reporter gene expression in brain. However not much is known about the mechanisms that control expression of the human PLP1 gene (hPLP1). Therefore this review will focus on sequences in hPLP1 intron 1 DNA deemed important for hPLP1 gene activity as well as a couple of ''human-specific'' supplementary exons within the first intron which are utilized to generate novel splice variants, and the potential role that these sequences may play in PLP1-linked disorders.

Research paper thumbnail of A Myelin Proteolipid Protein-LacZ Fusion Protein Is Developmentally Regulated and Targeted to the Myelin Membrane in Transgel c Mice

Abstract. Transgenic mice were generated with a fusion gene carrying a portion of the murine myel... more Abstract. Transgenic mice were generated with a fusion gene carrying a portion of the murine myelin proteolipid protein (PLP) gene, including the first intron, fused to the E. coli LacZ gene. Three transgenic lines were derived and all lines expressed the transgene in central nervous system white matter as measured by a histochemical assay for the detection of/~-galactosidase activity. PLP-LacZ transgene expression was regulated in both a spatial and temporal manner, consistent with endogenous PLP expression. Moreover, the transgene was expressed specifically in oligodendrocytes from primary mixed glial cultures prepared from transgenic mouse brains and appeared to be developmentally regulated in vitro as well. Transgene expression occurred in embryos, presumably in pre- or

Research paper thumbnail of Ethanol modulation of hippocampal neuroinflammation, myelination, and neurodevelopment in a postnatal mouse model of fetal alcohol spectrum disorders

Neurotoxicology and teratology, 2021

Fetal alcohol spectrum disorders (FASD) are alarmingly common and result in significant personal ... more Fetal alcohol spectrum disorders (FASD) are alarmingly common and result in significant personal and societal loss. Neuropathology of the hippocampus is common in FASD leading to aberrant cognitive function. In the current study, we evaluated the effects of ethanol on the expression of a targeted set of molecules involved in neuroinflammation, myelination, neurotransmission, and neuron function in the developing hippocampus in a postnatal model of FASD. Mice were treated with ethanol from P4-P9, hippocampi were isolated 24 h after the final treatment at P10, and mRNA levels were quantitated by qRT-PCR. We evaluated the effects of ethanol on both pro-inflammatory and anti-inflammatory molecules in the hippocampus and identified novel mechanisms by which ethanol induces neuroinflammation. We further demonstrated that ethanol decreased expression of molecules associated with mature oligodendrocytes and greatly diminished expression of a lacZ reporter driven by the first half of the mye...

Research paper thumbnail of Enhanced Gastrointestinal Expression of Cytosolic Malic Enzyme (ME1) Induces Intestinal and Liver Lipogenic Gene Expression and Intestinal Cell Proliferation in Mice

The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic en... more The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic enzyme 1 (ME1) is an enzyme that generates NADPH used in fatty acid and cholesterol biosynthesis. Previous work has correlated liver and adipose ME1 expression with susceptibility to obesity and diabetes; however, the contributions of intestine-expressed ME1 to these conditions are unknown. We generated transgenic (Tg) mice expressing rat ME1 in the gastrointestinal epithelium under the control of the murine villin1 promoter/enhancer. Levels of intestinal ME1 protein (endogenous plus transgene) were greater in Tg than wildtype (WT) littermates. Effects of elevated intestinal ME1 on body weight, circulating insulin, select adipocytokines, blood glucose, and metabolism-related genes were examined. Male Tg mice fed a high-fat (HF) diet gained significantly more body weight than WT male littermates and had heavier livers. ME1-Tg mice had deeper intestinal and colon crypts, a greater intestinal...

Research paper thumbnail of The wmN1 enhancer region in intron 1 is required for expression of human PLP1

Glia, Jan 23, 2018

The myelin proteolipid protein gene (PLP1) encodes the most abundant protein present in myelin fr... more The myelin proteolipid protein gene (PLP1) encodes the most abundant protein present in myelin from the central nervous system (CNS). Its expression must be tightly controlled as evidenced by mutations that alter PLP1 dosage; both overexpression (elevated PLP1 copy number) and lack thereof (PLP1 deletion) result in X-linked genetic disorders in man. However, not much is known about the mechanisms that govern expression of the human gene. To address this, transgenic mice were generated which utilize human PLP1 (hPLP1) sequences (proximal 6.2 kb of 5'-flanking DNA to the first 38 bp of exon 2) to drive expression of a lacZ reporter cassette. LoxP sites were incorporated around a 1.5-kb section of hPLP1 intron 1 since it contains sequence orthologous to the wmN1 region from mouse which, previously, was shown to augment expression of a minimally-promoted transgene coincident with the active myelination period of CNS development. Eight transgenic lines were generated with the parenta...

Research paper thumbnail of Inside Back Cover, Volume 41, Issue 1

Research paper thumbnail of The wmN1 Enhancer Region of the Mouse Myelin Proteolipid Protein Gene (mPlp1) is Indispensable for Expression of an mPlp1-lacZ Transgene in Both the CNS and PNS

Research paper thumbnail of Xq22 deletions and correlation with distinct neurological disease traits in females: further evidence for a contiguous gene syndrome

Research paper thumbnail of {"__content__"=>"A Transgenic Mouse Model to Selectively Identify α Na,K-ATPase Expressing Cells in the Nervous System.", "sub"=>{"__content__"=>"3"}}

Neuroscience, Jan 19, 2018

The α Na,K-ATPase (αNKA) is one of four known α isoforms of the mammalian transporter. A deficien... more The α Na,K-ATPase (αNKA) is one of four known α isoforms of the mammalian transporter. A deficiency in αNKA is linked to severe movement control disorders. Understanding the pathogenesis of these disorders is limited by an incomplete knowledge of αNKA expression in the brain as well as the challenges associated with identifying living cells that express the isoform for subsequent electrophysiological studies. To address this problem, transgenic mice were generated on the C57BL/6 genetic background, which utilize the mouse α subunit gene (Atp1a3) promoter to drive the expression of ZsGreen1 fluorescent protein. Consistent with published results on αNKA distribution, a ZsGreen1 signal was detected in the brain, but not in the liver, with Atp1a3-ZsGreen1 transgenic mice. The intensity of ZsGreen1 fluorescence in neuronal cell bodies varied considerably in the brain, being highest in the brainstem, deep cerebellar and select thalamic nuclei, and relatively weak in cortical regions. Fluo...

Research paper thumbnail of Effects of Intron 1 Sequences on Human PLP1 Expression: Implications for PLP1-Related Disorders

ASN Neuro

Alterations in the myelin proteolipid protein gene ( PLP1) may result in rare X-linked disorders ... more Alterations in the myelin proteolipid protein gene ( PLP1) may result in rare X-linked disorders in humans such as Pelizaeus–Merzbacher disease and spastic paraplegia type 2. PLP1 expression must be tightly regulated since null mutations, as well as elevated PLP1 copy number, both lead to disease. Previous studies with Plp1-lacZ transgenic mice have demonstrated that mouse Plp1 ( mPlp1) intron 1 DNA (which accounts for slightly more than half of the gene) is required for the mPlp1 promoter to drive significant levels of reporter gene expression in brain. However not much is known about the mechanisms that control expression of the human PLP1 gene ( hPLP1). Therefore this review will focus on sequences in hPLP1 intron 1 DNA deemed important for hPLP1 gene activity as well as a couple of “human-specific” supplementary exons within the first intron which are utilized to generate novel splice variants, and the potential role that these sequences may play in PLP1-linked disorders.

Research paper thumbnail of Functional Characterization of a cis-Acting DNA Antisilencer Region that Modulates Myelin Proteolipid Protein Gene Expression

J Neurochem, 2002

Regulation of myelin proteolipid protein (PLP:) gene expression is tightly controlled, both spati... more Regulation of myelin proteolipid protein (PLP:) gene expression is tightly controlled, both spatially and temporally. Previously, we have shown with transgenic mice that a PLP:-lacZ fusion gene (which includes the entire sequence for PLP: intron 1 DNA) is regulated in a similar manner to endogenous PLP: gene expression. Furthermore, by deletion-transfection analyses using assorted PLP:-lacZ constructs with partial deletion of PLP: intron 1 sequences, we have shown that the first intron possesses an antisilencer region that is capable of over-coming repression mediated by two distinct regions located elsewhere within intron 1 DNA. Here, we report the ability of various fragments encompassing the antisilencer region to restore beta-galactosidase activity when inserted into PLP:-lacZ constructs, which originally exhibited low levels of beta-galactosidase activity. Additional constructs were generated to test the effects of these antisilencer-containing fragments in constructs that are missing either one or both of the negative regulatory regions that are overridden during antisilencing. Transfection analyses, in conjunction with protein-DNA binding assays, suggest that several nuclear factors are necessary for derepression of PLP: gene activity in an oligodendroglial cell line. Moreover, either the "core" or complete antisilencing region can act in an additive or synergistic fashion when multiple copies are inserted into the Plp-lacZ constructs.

Research paper thumbnail of Antisilencing: Myelin Proteolipid Protein Gene Expression in Oligodendrocytes Is Regulated via Derepression

J Neurochem, 2002

Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic g... more Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic genes and were identified by their ability not to augment gene expression per se but to override repression mediated via negative transcription regulatory elements. Here we report the first case of antisilencing for a neural-specific gene, the myelin proteolipid protein (PLP) gene (Plp). PLP is the most abundant protein found in CNS myelin. The protein is synthesized in oligodendrocytes, and its expression is regulated developmentally. Previously we have shown that a PLP-lacZ transgene (which includes the entire sequence for Plp intron 1) is regulated in mice, in a manner consistent with the spatial and temporal expression of the endogenous Plp gene. In the present report, we demonstrate by transfection analyses, using various PLP-lacZ deletion constructs, that Plp intron 1 DNA contains multiple elements that collectively regulate Plp gene expression in oligodendrocytes. One of these regulatory elements functions as an antisilencer element, which acts to override repression mediated by at least two negative regulatory elements located elsewhere within Plp intron 1 DNA. The mechanism for antisilencing appears to be complex as the intragenic region that mediates this function binds multiple nuclear factors specifically.

Research paper thumbnail of Antisilencing: Myelin Proteolipid Protein Gene Expression in Oligodendrocytes Is Regulated via Derepression

J Neurochem, 2002

Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic g... more Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic genes and were identified by their ability not to augment gene expression per se but to override repression mediated via negative transcription regulatory elements. Here we report the first case of antisilencing for a neural-specific gene, the myelin proteolipid protein (PLP) gene (Plp). PLP is the most abundant protein found in CNS myelin. The protein is synthesized in oligodendrocytes, and its expression is regulated developmentally. Previously we have shown that a PLP-lacZ transgene (which includes the entire sequence for Plp intron 1) is regulated in mice, in a manner consistent with the spatial and temporal expression of the endogenous Plp gene. In the present report, we demonstrate by transfection analyses, using various PLP-lacZ deletion constructs, that Plp intron 1 DNA contains multiple elements that collectively regulate Plp gene expression in oligodendrocytes. One of these regulatory elements functions as an antisilencer element, which acts to override repression mediated by at least two negative regulatory elements located elsewhere within Plp intron 1 DNA. The mechanism for antisilencing appears to be complex as the intragenic region that mediates this function binds multiple nuclear factors specifically.

Research paper thumbnail of Enhanced gastrointestinal expression of cytosolic malic enzyme (ME1) induces intestinal and liver lipogenic gene expression and intestinal cell proliferation in mice

PloS one, 2014

The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic en... more The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic enzyme 1 (ME1) is an enzyme that generates NADPH used in fatty acid and cholesterol biosynthesis. Previous work has correlated liver and adipose ME1 expression with susceptibility to obesity and diabetes; however, the contributions of intestine-expressed ME1 to these conditions are unknown. We generated transgenic (Tg) mice expressing rat ME1 in the gastrointestinal epithelium under the control of the murine villin1 promoter/enhancer. Levels of intestinal ME1 protein (endogenous plus transgene) were greater in Tg than wildtype (WT) littermates. Effects of elevated intestinal ME1 on body weight, circulating insulin, select adipocytokines, blood glucose, and metabolism-related genes were examined. Male Tg mice fed a high-fat (HF) diet gained significantly more body weight than WT male littermates and had heavier livers. ME1-Tg mice had deeper intestinal and colon crypts, a greater intestinal...

Research paper thumbnail of Mutations in the Myelin Proteolipid Protein Gene Alter Oligodendrocyte Gene Expression in Jimpy and Jimpy msd Mice

Journal of Neurochemistry, 1991

The mouse myelin proteolipid protein (PLP) gene has been studied in normal and jimpymd mice. Pote... more The mouse myelin proteolipid protein (PLP) gene has been studied in normal and jimpymd mice. Potential upstream regulatory regions of the normal gene have been

Research paper thumbnail of Discrete positive and negative thyroid hormone-responsive transcription regulatory elements of the rat growth hormone gene

Journal of Biological Chemistry

We have recently shown that a thyroid hormone-responsive transcription stimulatory element exists... more We have recently shown that a thyroid hormone-responsive transcription stimulatory element exists in the 5'-flanking DNA near the rat growth hormone (rGH) gene (Crew, M. D., and Spindler, S. R. (1986) J. Biol. Chem. 261, 5018-5022). Progressive deletion-transfection analysis of the 5' end of the gene has led to the identification of two genetic elements responsive to thyroid hormone. The first of these is a thyroid hormone-responsive transcription stimulatory element, or TSE. The TSE induced a thyroid hormone-dependent induction-attenuation transcription cycle similar to that of the natural rGH gene. Deletion of sequences between positions -254 and -241 in the rGH 5'-flanking DNA eliminated TSE activity. The second regulatory element is a thyroid hormone-responsive transcription inhibitory element (TIE). When this element was active, thyroid hormone strongly but transiently inhibited rGH promoter utilization. Deletion of sequences between nucleotides -46 and -21 abolished the effects of the TIE. To determine whether the TSE and TIE are enhancer-like, we ligated various regions of rat growth hormone 5'-flanking DNA containing these elements to a chimeric test gene containing the Herpes simplex virus thymidine kinase promoter. Thyroid hormone activated heterologous promoter utilization when a rat growth hormone 5'-flanking DNA fragment containing the TSE (-520 to -115) was linked in cis, regardless of the distance or orientation of the TSE with respect to the promoter. These data suggest that the TSE is a thyroid hormone-dependent enhancer. In contrast, when the TIE was placed immediately 5' to the thymidine kinase promoter, transcription was not effected by 3,5,3'-L-triiodothyronine, suggesting that the TIE is not enhancer-like.

Research paper thumbnail of Plp1 in the enteric nervous system is preferentially expressed during early postnatal development in mouse as DM20, whose expression appears reliant on an intronic enhancer

Frontiers in Cellular Neuroscience

Recently, the myelin proteolipid protein gene (Plp1) was shown to be expressed in the glia of the... more Recently, the myelin proteolipid protein gene (Plp1) was shown to be expressed in the glia of the enteric nervous system (ENS) in mouse. However, beyond this, not much is known about its expression in the intestine. To address this matter, we investigated Plp1 expression at the mRNA and protein levels in the intestine of mice at different ages (postnatal days 2, 9, 21, and 88). In this study, we show that Plp1 expression preferentially occurs during early postnatal development, primarily as the DM20 isoform. Western blot analysis indicated that DM20 migrated according to its formula weight when isolated from the intestine. However, mobilities of both PLP and DM20 were faster than expected when procured from the brain. The 6.2hPLP(+)Z/FL transgene, which uses the first half of the human PLP1 gene to drive expression of a lacZ reporter gene, recapitulated the developmental pattern observed with the native gene in the intestine, indicating that it can be used as a proxy for Plp1 gene e...

Research paper thumbnail of PLP1-lacZ transgenic mice reveal that splice variants containing “human-specific” exons are relatively minor in comparison to the archetypal transcript and that an upstream regulatory element bolsters expression during early postnatal brain development

Frontiers in Cellular Neuroscience

Much of what is known about the mechanisms that control the developmental expression of the myeli... more Much of what is known about the mechanisms that control the developmental expression of the myelin proteolipid protein gene (PLP1) has been attained through use of transgenic animal models. In this study, we analyzed expression of related transgenes which utilize PLP1 genomic DNA from either human or mouse to drive expression of a lacZ reporter. Human PLP1 (hPLP1) sequence span either the proximal 6.2 or 2.7 kb of 5′-flanking DNA to an internal site in Exon 2, while those from mouse comprise the proximal 2.3 kb of 5′-flanking DNA to an analogous site in Exon 2. Transgenes with hPLP1 sequence were named, in part, to the amount of upstream sequence they have [6.2hPLP(+)Z/FL and 2.7hPLP(+)Z]. The transgene containing mouse sequence is referred to here as mPLP(+)Z, to denote the species origin of PLP1 DNA. Mice which harbor the 6.2hPLP(+)Z/FL transgene were used as a model system to investigate the developmental expression of splice variants that incorporate supplementary exons from wha...

Research paper thumbnail of Please Note Change in Location

AGENDA 1) Announcements 2) Minutes of the previous meeting and business arising from the minutes ... more AGENDA 1) Announcements 2) Minutes of the previous meeting and business arising from the minutes 3) Question period

Research paper thumbnail of Expression of a Myelin Proteolipid Protein (Plp)-lacZ Transgene is Reduced in both the CNS and PNS of Plp jp Mice

Neurochemical Research, 2006

Jimpy (Plp jp ) is an X-linked recessive mutation in mice that causes CNS dysmyelination and earl... more Jimpy (Plp jp ) is an X-linked recessive mutation in mice that causes CNS dysmyelination and early death in affected males. It results from a point mutation in the acceptor splice site of myelin proteolipid protein (Plp) exon 5, producing transcripts that are missing exon 5, with a concomitant shift in the downstream reading frame. Expression of the mutant PLP product in Plp jp males leads to hypomyelination and oligodendrocyte death. Expression of our Plp-lacZ fusion gene, PLP(+)Z, in transgenic mice is an excellent readout for endogenous Plp transcriptional activity. The current studies assess expression of the PLP(+)Z transgene in the Plp jp background. These studies demonstrate that expression of the transgene is decreased in both the central and peripheral nervous systems of affected Plp jp males. Thus, expression of mutated PLP protein downregulates Plp gene activity both in oligodendrocytes, which eventually die, and in Schwann cells, which are apparently unaffected in Plp jp mice.

Research paper thumbnail of Effects of Intron 1 Sequences on Human PLP1 Expression: Implications for PLP1-Related Disorders

ASN Neuro, Jul 24, 2017

Alterations in the myelin proteolipid protein gene (PLP1) may result in rare X-linked disorders i... more Alterations in the myelin proteolipid protein gene (PLP1) may result in rare X-linked disorders in humans such as Pelizaeus-Merzbacher disease and spastic paraplegia type 2. PLP1 expression must be tightly regulated since null mutations, as well as elevated PLP1 copy number, both lead to disease. Previous studies with Plp1-lacZ transgenic mice have demonstrated that mouse Plp1 (mPlp1) intron 1 DNA (which accounts for slightly more than half of the gene) is required for the mPlp1 promoter to drive significant levels of reporter gene expression in brain. However not much is known about the mechanisms that control expression of the human PLP1 gene (hPLP1). Therefore this review will focus on sequences in hPLP1 intron 1 DNA deemed important for hPLP1 gene activity as well as a couple of ''human-specific'' supplementary exons within the first intron which are utilized to generate novel splice variants, and the potential role that these sequences may play in PLP1-linked disorders.

Research paper thumbnail of A Myelin Proteolipid Protein-LacZ Fusion Protein Is Developmentally Regulated and Targeted to the Myelin Membrane in Transgel c Mice

Abstract. Transgenic mice were generated with a fusion gene carrying a portion of the murine myel... more Abstract. Transgenic mice were generated with a fusion gene carrying a portion of the murine myelin proteolipid protein (PLP) gene, including the first intron, fused to the E. coli LacZ gene. Three transgenic lines were derived and all lines expressed the transgene in central nervous system white matter as measured by a histochemical assay for the detection of/~-galactosidase activity. PLP-LacZ transgene expression was regulated in both a spatial and temporal manner, consistent with endogenous PLP expression. Moreover, the transgene was expressed specifically in oligodendrocytes from primary mixed glial cultures prepared from transgenic mouse brains and appeared to be developmentally regulated in vitro as well. Transgene expression occurred in embryos, presumably in pre- or

Research paper thumbnail of Ethanol modulation of hippocampal neuroinflammation, myelination, and neurodevelopment in a postnatal mouse model of fetal alcohol spectrum disorders

Neurotoxicology and teratology, 2021

Fetal alcohol spectrum disorders (FASD) are alarmingly common and result in significant personal ... more Fetal alcohol spectrum disorders (FASD) are alarmingly common and result in significant personal and societal loss. Neuropathology of the hippocampus is common in FASD leading to aberrant cognitive function. In the current study, we evaluated the effects of ethanol on the expression of a targeted set of molecules involved in neuroinflammation, myelination, neurotransmission, and neuron function in the developing hippocampus in a postnatal model of FASD. Mice were treated with ethanol from P4-P9, hippocampi were isolated 24 h after the final treatment at P10, and mRNA levels were quantitated by qRT-PCR. We evaluated the effects of ethanol on both pro-inflammatory and anti-inflammatory molecules in the hippocampus and identified novel mechanisms by which ethanol induces neuroinflammation. We further demonstrated that ethanol decreased expression of molecules associated with mature oligodendrocytes and greatly diminished expression of a lacZ reporter driven by the first half of the mye...

Research paper thumbnail of Enhanced Gastrointestinal Expression of Cytosolic Malic Enzyme (ME1) Induces Intestinal and Liver Lipogenic Gene Expression and Intestinal Cell Proliferation in Mice

The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic en... more The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic enzyme 1 (ME1) is an enzyme that generates NADPH used in fatty acid and cholesterol biosynthesis. Previous work has correlated liver and adipose ME1 expression with susceptibility to obesity and diabetes; however, the contributions of intestine-expressed ME1 to these conditions are unknown. We generated transgenic (Tg) mice expressing rat ME1 in the gastrointestinal epithelium under the control of the murine villin1 promoter/enhancer. Levels of intestinal ME1 protein (endogenous plus transgene) were greater in Tg than wildtype (WT) littermates. Effects of elevated intestinal ME1 on body weight, circulating insulin, select adipocytokines, blood glucose, and metabolism-related genes were examined. Male Tg mice fed a high-fat (HF) diet gained significantly more body weight than WT male littermates and had heavier livers. ME1-Tg mice had deeper intestinal and colon crypts, a greater intestinal...

Research paper thumbnail of The wmN1 enhancer region in intron 1 is required for expression of human PLP1

Glia, Jan 23, 2018

The myelin proteolipid protein gene (PLP1) encodes the most abundant protein present in myelin fr... more The myelin proteolipid protein gene (PLP1) encodes the most abundant protein present in myelin from the central nervous system (CNS). Its expression must be tightly controlled as evidenced by mutations that alter PLP1 dosage; both overexpression (elevated PLP1 copy number) and lack thereof (PLP1 deletion) result in X-linked genetic disorders in man. However, not much is known about the mechanisms that govern expression of the human gene. To address this, transgenic mice were generated which utilize human PLP1 (hPLP1) sequences (proximal 6.2 kb of 5'-flanking DNA to the first 38 bp of exon 2) to drive expression of a lacZ reporter cassette. LoxP sites were incorporated around a 1.5-kb section of hPLP1 intron 1 since it contains sequence orthologous to the wmN1 region from mouse which, previously, was shown to augment expression of a minimally-promoted transgene coincident with the active myelination period of CNS development. Eight transgenic lines were generated with the parenta...

Research paper thumbnail of Inside Back Cover, Volume 41, Issue 1

Research paper thumbnail of The wmN1 Enhancer Region of the Mouse Myelin Proteolipid Protein Gene (mPlp1) is Indispensable for Expression of an mPlp1-lacZ Transgene in Both the CNS and PNS

Research paper thumbnail of Xq22 deletions and correlation with distinct neurological disease traits in females: further evidence for a contiguous gene syndrome

Research paper thumbnail of {"__content__"=>"A Transgenic Mouse Model to Selectively Identify α Na,K-ATPase Expressing Cells in the Nervous System.", "sub"=>{"__content__"=>"3"}}

Neuroscience, Jan 19, 2018

The α Na,K-ATPase (αNKA) is one of four known α isoforms of the mammalian transporter. A deficien... more The α Na,K-ATPase (αNKA) is one of four known α isoforms of the mammalian transporter. A deficiency in αNKA is linked to severe movement control disorders. Understanding the pathogenesis of these disorders is limited by an incomplete knowledge of αNKA expression in the brain as well as the challenges associated with identifying living cells that express the isoform for subsequent electrophysiological studies. To address this problem, transgenic mice were generated on the C57BL/6 genetic background, which utilize the mouse α subunit gene (Atp1a3) promoter to drive the expression of ZsGreen1 fluorescent protein. Consistent with published results on αNKA distribution, a ZsGreen1 signal was detected in the brain, but not in the liver, with Atp1a3-ZsGreen1 transgenic mice. The intensity of ZsGreen1 fluorescence in neuronal cell bodies varied considerably in the brain, being highest in the brainstem, deep cerebellar and select thalamic nuclei, and relatively weak in cortical regions. Fluo...

Research paper thumbnail of Effects of Intron 1 Sequences on Human PLP1 Expression: Implications for PLP1-Related Disorders

ASN Neuro

Alterations in the myelin proteolipid protein gene ( PLP1) may result in rare X-linked disorders ... more Alterations in the myelin proteolipid protein gene ( PLP1) may result in rare X-linked disorders in humans such as Pelizaeus–Merzbacher disease and spastic paraplegia type 2. PLP1 expression must be tightly regulated since null mutations, as well as elevated PLP1 copy number, both lead to disease. Previous studies with Plp1-lacZ transgenic mice have demonstrated that mouse Plp1 ( mPlp1) intron 1 DNA (which accounts for slightly more than half of the gene) is required for the mPlp1 promoter to drive significant levels of reporter gene expression in brain. However not much is known about the mechanisms that control expression of the human PLP1 gene ( hPLP1). Therefore this review will focus on sequences in hPLP1 intron 1 DNA deemed important for hPLP1 gene activity as well as a couple of “human-specific” supplementary exons within the first intron which are utilized to generate novel splice variants, and the potential role that these sequences may play in PLP1-linked disorders.

Research paper thumbnail of Functional Characterization of a cis-Acting DNA Antisilencer Region that Modulates Myelin Proteolipid Protein Gene Expression

J Neurochem, 2002

Regulation of myelin proteolipid protein (PLP:) gene expression is tightly controlled, both spati... more Regulation of myelin proteolipid protein (PLP:) gene expression is tightly controlled, both spatially and temporally. Previously, we have shown with transgenic mice that a PLP:-lacZ fusion gene (which includes the entire sequence for PLP: intron 1 DNA) is regulated in a similar manner to endogenous PLP: gene expression. Furthermore, by deletion-transfection analyses using assorted PLP:-lacZ constructs with partial deletion of PLP: intron 1 sequences, we have shown that the first intron possesses an antisilencer region that is capable of over-coming repression mediated by two distinct regions located elsewhere within intron 1 DNA. Here, we report the ability of various fragments encompassing the antisilencer region to restore beta-galactosidase activity when inserted into PLP:-lacZ constructs, which originally exhibited low levels of beta-galactosidase activity. Additional constructs were generated to test the effects of these antisilencer-containing fragments in constructs that are missing either one or both of the negative regulatory regions that are overridden during antisilencing. Transfection analyses, in conjunction with protein-DNA binding assays, suggest that several nuclear factors are necessary for derepression of PLP: gene activity in an oligodendroglial cell line. Moreover, either the "core" or complete antisilencing region can act in an additive or synergistic fashion when multiple copies are inserted into the Plp-lacZ constructs.

Research paper thumbnail of Antisilencing: Myelin Proteolipid Protein Gene Expression in Oligodendrocytes Is Regulated via Derepression

J Neurochem, 2002

Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic g... more Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic genes and were identified by their ability not to augment gene expression per se but to override repression mediated via negative transcription regulatory elements. Here we report the first case of antisilencing for a neural-specific gene, the myelin proteolipid protein (PLP) gene (Plp). PLP is the most abundant protein found in CNS myelin. The protein is synthesized in oligodendrocytes, and its expression is regulated developmentally. Previously we have shown that a PLP-lacZ transgene (which includes the entire sequence for Plp intron 1) is regulated in mice, in a manner consistent with the spatial and temporal expression of the endogenous Plp gene. In the present report, we demonstrate by transfection analyses, using various PLP-lacZ deletion constructs, that Plp intron 1 DNA contains multiple elements that collectively regulate Plp gene expression in oligodendrocytes. One of these regulatory elements functions as an antisilencer element, which acts to override repression mediated by at least two negative regulatory elements located elsewhere within Plp intron 1 DNA. The mechanism for antisilencing appears to be complex as the intragenic region that mediates this function binds multiple nuclear factors specifically.

Research paper thumbnail of Antisilencing: Myelin Proteolipid Protein Gene Expression in Oligodendrocytes Is Regulated via Derepression

J Neurochem, 2002

Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic g... more Antisilencer or antirepressor elements have been described, thus far, for only a few eukaryotic genes and were identified by their ability not to augment gene expression per se but to override repression mediated via negative transcription regulatory elements. Here we report the first case of antisilencing for a neural-specific gene, the myelin proteolipid protein (PLP) gene (Plp). PLP is the most abundant protein found in CNS myelin. The protein is synthesized in oligodendrocytes, and its expression is regulated developmentally. Previously we have shown that a PLP-lacZ transgene (which includes the entire sequence for Plp intron 1) is regulated in mice, in a manner consistent with the spatial and temporal expression of the endogenous Plp gene. In the present report, we demonstrate by transfection analyses, using various PLP-lacZ deletion constructs, that Plp intron 1 DNA contains multiple elements that collectively regulate Plp gene expression in oligodendrocytes. One of these regulatory elements functions as an antisilencer element, which acts to override repression mediated by at least two negative regulatory elements located elsewhere within Plp intron 1 DNA. The mechanism for antisilencing appears to be complex as the intragenic region that mediates this function binds multiple nuclear factors specifically.

Research paper thumbnail of Enhanced gastrointestinal expression of cytosolic malic enzyme (ME1) induces intestinal and liver lipogenic gene expression and intestinal cell proliferation in mice

PloS one, 2014

The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic en... more The small intestine participates in lipid digestion, metabolism and transport. Cytosolic malic enzyme 1 (ME1) is an enzyme that generates NADPH used in fatty acid and cholesterol biosynthesis. Previous work has correlated liver and adipose ME1 expression with susceptibility to obesity and diabetes; however, the contributions of intestine-expressed ME1 to these conditions are unknown. We generated transgenic (Tg) mice expressing rat ME1 in the gastrointestinal epithelium under the control of the murine villin1 promoter/enhancer. Levels of intestinal ME1 protein (endogenous plus transgene) were greater in Tg than wildtype (WT) littermates. Effects of elevated intestinal ME1 on body weight, circulating insulin, select adipocytokines, blood glucose, and metabolism-related genes were examined. Male Tg mice fed a high-fat (HF) diet gained significantly more body weight than WT male littermates and had heavier livers. ME1-Tg mice had deeper intestinal and colon crypts, a greater intestinal...

Research paper thumbnail of Mutations in the Myelin Proteolipid Protein Gene Alter Oligodendrocyte Gene Expression in Jimpy and Jimpy msd Mice

Journal of Neurochemistry, 1991

The mouse myelin proteolipid protein (PLP) gene has been studied in normal and jimpymd mice. Pote... more The mouse myelin proteolipid protein (PLP) gene has been studied in normal and jimpymd mice. Potential upstream regulatory regions of the normal gene have been

Research paper thumbnail of Discrete positive and negative thyroid hormone-responsive transcription regulatory elements of the rat growth hormone gene

Journal of Biological Chemistry

We have recently shown that a thyroid hormone-responsive transcription stimulatory element exists... more We have recently shown that a thyroid hormone-responsive transcription stimulatory element exists in the 5'-flanking DNA near the rat growth hormone (rGH) gene (Crew, M. D., and Spindler, S. R. (1986) J. Biol. Chem. 261, 5018-5022). Progressive deletion-transfection analysis of the 5' end of the gene has led to the identification of two genetic elements responsive to thyroid hormone. The first of these is a thyroid hormone-responsive transcription stimulatory element, or TSE. The TSE induced a thyroid hormone-dependent induction-attenuation transcription cycle similar to that of the natural rGH gene. Deletion of sequences between positions -254 and -241 in the rGH 5'-flanking DNA eliminated TSE activity. The second regulatory element is a thyroid hormone-responsive transcription inhibitory element (TIE). When this element was active, thyroid hormone strongly but transiently inhibited rGH promoter utilization. Deletion of sequences between nucleotides -46 and -21 abolished the effects of the TIE. To determine whether the TSE and TIE are enhancer-like, we ligated various regions of rat growth hormone 5'-flanking DNA containing these elements to a chimeric test gene containing the Herpes simplex virus thymidine kinase promoter. Thyroid hormone activated heterologous promoter utilization when a rat growth hormone 5'-flanking DNA fragment containing the TSE (-520 to -115) was linked in cis, regardless of the distance or orientation of the TSE with respect to the promoter. These data suggest that the TSE is a thyroid hormone-dependent enhancer. In contrast, when the TIE was placed immediately 5' to the thymidine kinase promoter, transcription was not effected by 3,5,3'-L-triiodothyronine, suggesting that the TIE is not enhancer-like.