Yolande Lemaigre-Dubreuil

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Retinoic acid receptor-related orphan receptor alpha (RORalpha) is a transcription factor belonging to the superfamily of nuclear receptors. Disruption of the Rora gene in the mouse results in a defect in the development of Purkinje cells leading to a cerebellar atrophy, which suggests a neuroprotective role for RORalpha. To test this hypothesis, the(More)
The staggerer mutation causes dysgenesis of the cerebellar cortex in the homozygous mutant (Rora(sg)/Rora(sg)). The mutation acts intrinsically within the Purkinje cells (PCs), leading to cytological abnormalities and a severe deficit in the number of these cells. In contrast, in the heterozygous staggerer (Rora(+)/Rora(sg)), the cytoarchitecture of the(More)
Ceramide, the central molecule of the sphingomyelin pathway, serves as a second messenger for cellular functions ranging from proliferation and differentiation to growth arrest and apoptosis. In this study we show that c2-ceramide induces apoptosis in primary cortical neuron cultures and that this effect correlates with differential modulation of(More)
Brain expression of Interleukin-1beta (IL-1beta) and its modulation have been extensively documented in different animal models. The majority of the studies were based on techniques such as RT-PCR, RIA and ELISA using global extracts. Meningeal tissue or choroid plexus both belong to the peripheral compartment. Thus, their presence in nervous tissue(More)
Prion diseases are neurodegenerative pathologies characterized by apoptotic neuronal death. Although the late execution phase of neuronal apoptosis is beginning to be characterized, the sequence of events occurring during the early decision phase is not yet well known. In murine cortical neurons in primary culture, apoptosis was first induced by exposure to(More)
In the CNS, Bcl-2 is an antiapoptotic gene involved in the regulation of neuronal death. Transgenic mice overexpressing the human gene Bcl-2 (Hu-bcl-2 mice) showed delayed acquisition in two tasks requiring them to find a hidden platform starting from either a random or a constant starting location. The same mice were not deficient in another task requiring(More)
The number of cerebellar Purkinje cells is increased by over 40% in young transgenic mice that overexpress a human Bcl-2 transgene (Hu-Bcl-2). To determine whether the Bcl-2-mediated rescue of Purkinje cells persists through life, the numbers of Purkinje cells were estimated in 6-, 12-, 18-, and 24-month-old Hu-Bcl-2 transgenic mice and age-matched(More)
The homozygous mutant mouse staggerer (RORa(sg)/RORa(sg)), was initially described as ataxic, due to the presence of massive neurodegeneration in the cerebellum [Science 136 (1962) 610]. The identification of the widely expressed Retinoic acid receptor-related Orphan Receptor, NR1F1 (RORalpha) gene as the site of mutation in the staggerer mouse has led to(More)
Correct neural function depends on precisely organized connectivity, which is refined from broader projections through synaptic/collateral elimination. In the rat, olivocerebellar topography is refined by regression of multiple climbing fiber (CF) innervation of Purkinje cells (PC) during the first two postnatal weeks. The molecules that initiate this(More)
Ror alpha is an orphan nuclear receptor. In homozygous staggerer mutant mice (Ror alpha(sg/sg)), a deletion within the Ror alpha gene leads to an overexpression of inflammatory cytokines. Because inflammation and hypoxia are 2 key stimuli of ischemia-induced angiogenesis, we studied the role of Ror alpha in this setting. Ischemia was induced by ligation of(More)