L-3,4-dihydroxyphenylalanine (levodopa) treatment is the major pharmacotherapy for Parkinson's disease. However, almost all patients receiving levodopa eventually develop debilitating involuntary movements (dyskinesia). While it is known that striatal spiny projection neurons (SPNs) are involved in the genesis of this movement disorder, the molecular basis of dyskinesia is not understood. In this study, we identify distinct cell-type-specific gene expression changes that occur in sub-classes of SPNs upon induction of a parkinsonian lesion followed by chronic levodopa treatment. We identify several hundred genes whose expression is correlated with levodopa dose, many of which are under the control of AP-1 and ERK signaling. In spite of homeostatic adaptations involving several signaling modulators, AP-1-dependent gene expression remains highly dysregulated in direct pathway SPNs (dSPNs) upon chronic levodopa treatment. We also discuss which molecular pathways are most likely to dampen abnormal dopaminoceptive signaling in spiny projection neurons, hence providing potential targets for antidyskinetic treatments in Parkinson's disease.
Molecular adaptations of striatal spiny projection neurons during levodopa-induced dyskinesia.
Specimen part, Treatment
View SamplesThe fidelity of sound transmission by cochlear implants in patients with sensorineural hearing loss could be greatly improved by increasing the number of frequency channels. This could be achieved by stimulating and guiding neurite outgrowth to reduce the distance between the implant's electrodes and the remnants of the spiral ganglion neurons. However, little is known about signaling pathways, besides those of neurotrophic factors, that are operational in the adult spiral ganglion. To systematically identify neuronal receptors for guidance cues in the adult cochlea, we conducted a genome-wide cDNA microarray screen with two-month-old CBA/CaJ mice. A meta-analysis of our data and those from older mice in two other studies revealed the presence of neuronal transmembrane receptors that represent all four established guidance pathwaysephrin, netrin, semaphorin, and slitin the mature cochlea as late as 15 months. In addition, we observed the expression of all known receptors for the Wnt morphogens, whose neuronal guidance function has only recently been recognized. In situ hybridizations located the mRNAs of the Wnt receptors frizzled 1, 4, 6, 9, and 10 specifically in adult spiral ganglion neurons. Finally, frizzled 9 protein was found in the growth cones of adult spiral ganglion neurons that were regenerating neurites in culture. We conclude from our results that adult spiral ganglion neurons are poised to respond to neurite damage, owing to the constitutive expression of a large and diverse collection of guidance receptors. Wnt signaling, in particular, emerges as a candidate pathway for guiding neurite outgrowth towards a cochlear implant after sensorineural hearing loss.
Expression of Wnt receptors in adult spiral ganglion neurons: frizzled 9 localization at growth cones of regenerating neurites.
Sex, Specimen part
View SamplesEctromelia virus (ECTV) has emerged as a valuable model for investigating the host-orthopoxvirus relationship as it relates to pathogenesis and the immune response. ECTV causes mousepox in most strains of mice, including BALB/c and DBA/2, and these are therefore classified as susceptible mice. Conversely, C57BL/6 and certain 129 strains display limited pathology and a very low mortality, and are thus classified as resistant. To understand the host genetic factors of different mouse strains in response to ECTV infection, we carried out a microarray analysis using Affymetrix Gene-Chip Mouse Genome Arrays of spleen tissues from BALB/c and C57BL/6 mice at 3 and 10 days post-ECTV infection.
Comparison of Host Gene Expression Profiles in Spleen Tissues of Genetically Susceptible and Resistant Mice during ECTV Infection.
Sex, Specimen part, Time
View SamplesThe glucocorticoid receptor overexpression in early life is sufficient to alter gene expression patterns for the rest of the animal's life.
Early-life forebrain glucocorticoid receptor overexpression increases anxiety behavior and cocaine sensitization.
Sex, Specimen part
View SamplesWe identify numerous miR-203 in vivo targets that are highly enriched for the promotion of cell cycle and cell division. Importantly, individual targets including p63, Skp2 and Msi2 play distinct roles downstream of miR-203 to regulate the cell cycle and long-term proliferation. Together, our findings reveal rapid and widespread impact of miR-203 on the self-renewal program during the epidermal differentiation and provide mechanistic insights for the potent role of miR-203 where coordinated repression of multiple targets is required for the function of this miRNA.
Rapid and widespread suppression of self-renewal by microRNA-203 during epidermal differentiation.
Specimen part
View SamplesWe are investigating hepatic transcriptional responses associated with castration and tumorigenic hepatitis induced by Helicobacter hepaticus infection in mature male A/JCr mice
Hepatocellular carcinoma associated with liver-gender disruption in male mice.
No sample metadata fields
View SamplesWe are investigating the transcriptional response of mice infected with Helicobacter hepaticus and links to liver cancer
Genetic susceptibility to chronic hepatitis is inherited codominantly in Helicobacter hepaticus-infected AB6F1 and B6AF1 hybrid male mice, and progression to hepatocellular carcinoma is linked to hepatic expression of lipogenic genes and immune function-associated networks.
No sample metadata fields
View SamplesNeo/null loss of Tfap2a in E10.5 mouse facial prominences
Tfap2a-dependent changes in mouse facial morphology result in clefting that can be ameliorated by a reduction in Fgf8 gene dosage.
Specimen part
View SamplesMLL-fusions may induce leukemogenic gene expression programs by recruiting the histone H3K79 methyltransferase to MLL-target promoters. We evaluated gene expression changes after cre-mediated loss of Dot1l in leukemia cells obtained from mice injected with MLL-9 transformed lineage negative bone marrow cells.
MLL-rearranged leukemia is dependent on aberrant H3K79 methylation by DOT1L.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Androgenetic haploid embryonic stem cells produce live transgenic mice.
Specimen part, Cell line
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