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P Roustan

Publications and source records attributed to P Roustan.

10 recordsLinked to original sources
PubMed2000

Analysis of prolactin-modulated gene expression profiles during the Nb2 cell cycle using differential screening techniques.

BACKGROUND: Rat Nb2-11C lymphoma cells are dependent on prolactin for proliferation and are widely used to study prolactin signaling pathways. To investigate the role of this hormone in the transcriptional mechanisms that underlie prolactin-stimulated mitogenesis, five different techniques were used to isolate differentially expressed transcripts: mRNA differential display, representational difference analysis (RDA), subtractive suppressive hybridization (SSH), analysis of weakly expressed candidate genes, and differential screening of an organized library. RESULTS: About 70 transcripts were found to be modulated in Nb2 cells following prolactin treatment. Of these, approximately 20 represent unknown genes. All cDNAs were characterized by northern blot analysis and categorized on the basis of their expression profiles and the functions of the known genes. We compared our data with other cell-cycle-regulated transcripts and found several new potential signaling molecules that may be involved in Nb2 cell growth. In addition, abnormalities in the expression patterns of several transcripts were detected in Nb2 cells, including the constitutive expression of the immediate-early gene EGR-1. Finally, we compared the differential screening techniques in terms of sensitivity, efficiency and occurrence of false positives. CONCLUSIONS: Using these techniques to determine which genes are differentially expressed in Nb2 lymphoma cells, we have obtained valuable insight into the potential functions of some of these genes in the cell cycle. Although this information is preliminary, comparison with other eukaryotic models of cell-cycle progression enables identification of expression abnormalities and proteins potentially involved in signal transduction, which could indicate new directions for research.

Animals↗
PubMed1997

In vivo adenovirus-mediated gene transfer to newborn rat retinal pigment epithelial cells.

A successful surgical access to the subretinal space is critical for achieving adenovirus-mediated gene transfer to the retinal pigment epithelial (RPE) cells or photoreceptor cells. We report a novel surgical approach allowing an efficient delivery of recombinant replication-deficient adenoviral vectors into the subretinal space of newborn rats. Our data suggest that this method may be useful for infecting reproducibly large area of the RPE cell layer of normal newborn rats and should be applicable to RCS pups. We also show the feasibility of infecting ex vivo RPE cells in culture using the same recombinant adenoviral vector.

Animals↗
PubMed1995

The rat phospholipase C beta 4 gene is expressed at high abundance in cerebellar Purkinje cells.

Inositol phospholipid-specific phospholipase C (PLC) generates two important second messengers, inositol triphosphate and diacylglycerol. The recently cloned rat PLC beta 4 cDNA is highly homologous to the norpA cDNA of Drosophila melanogaster. We have mapped the PLC beta 4 gene expression in rat brain tissue sections by in situ hybridization. The PLC beta 4 gene is expressed at high abundance in cerebellar Purkinje cells and neurones of the substantia nigra, the median geniculate bodies and the thalamic nuclei. PLC beta 4 transcripts are also detected in the mammillary nuclei, the neocortex, the habenula and the olfactory bulbs. The specific pattern of gene expression we have observed should help to clarify the relationships between the PLC beta 4 and various constituents of second-messenger systems involved in transduction mechanisms triggered by the stimulation of seven transmembrane domain receptors. The strong gene expression in Purkinje cells and retinal neurones suggests that PLC beta 4 may be involved in the pathogenesis of mouse and human neurological diseases characterized by ataxia and retinal degeneration.

Animals↗
PubMed1995

Genetic and physical mapping of five novel microsatellite markers on human Xp21.1-p11.22.

Five polymorphic CA-dinucleotide repeats, identified in cosmids from the short arm of the human X chromosome, have been characterized and localized to Xp21.1 (DXS572), Xp11.4 (DXS556, DXS574), and Xp11.22-p11.23 (DXS722, DXS573). Genetic mapping with respect to five reference markers that include the gene for CGD (CYBB in Xp21.1), complemented by physical mapping information, has indicated the order tel-DXS572-CYBB-DXS1110-DXS556-DXS574-D XS7-DXS426-DXS722-DXS573-DXS255-cen.

Animals↗
PubMed1993

Isolation and characterization of three microsatellite markers in the proximal long arm of the human X chromosome.

Three microsatellites have been identified in cosmids from the human X chromosome. The cosmids have been assigned locus numbers DXS554, DXS559, and DXS566 and have been localized to Xq12-q13 (DXS554 and DXS559) and Xq13 (DXS566). In addition, they have been genetically mapped in relation to the androgen receptor (AR), phosphoglycerate kinase 1, pseudogene 1 (PGK1P1), and phosphoglycerate kinase (PGK1) loci in the proximal long arm. Genetically, the localization of microsatellites at DXS554 and DXS566 is indistinguishable from PGK1, whereas that at DXS559 maps between AR and PGK1, close to PGK1P1. DXS566 is identical to the independently identified DXS441 marker. These markers should be useful for physical and genetic mapping in this region.

Alleles↗
PubMed1993

X chromosome linkage studies in familial Rett syndrome.

Four families, each with two individuals affected by Rett Syndrome (RS), were analysed using restriction fragment length polymorphisms and microsatellite markers from the X chromosome. In two of the families, X-linked dominant inheritance of the RS defect from a germinally mosaic mother could be assumed. Therefore, maternal X chromosome markers showing discordant inheritance were used to exclude regions of the X chromosome as locations of the RS gene. Much of the short arm could be excluded, including regions containing three candidate genes, OTC, synapsin 1 and synaptophysin. Although most of the long arm was inherited in common it was possible to exclude a centromeric region. Inheritance of X chromosome markers is also presented for two families with affected aunt-niece pairs, one of which has not been previously studied at the DNA level.

Chromosome Mapping↗
PubMed1989

Novel structures CTLA-2 alpha and CTLA-2 beta expressed in mouse activated T cells and mast cells and homologous to cysteine proteinase proregions.

Differential screening of a subtracted cDNA library led to the detection of two distinct but homologous mouse cDNA, called CTLA-2 alpha and CTLA-2 beta. The corresponding transcripts have a tissue distribution restricted to T lymphocytes, where they are inducible upon activation, and to mast cells. The open-frame regions of both cDNA encode proteins homologous to cysteine proteinase precursors, remarkably, however, only to the proregion of these. The ctla-2 alpha and ctla-2 beta genes both map to the C1 band of mouse chromosome 13. Sequence comparisons suggest that the proregion of an ancestor proteinase gene evolved to the ctla-2 genes by successive duplications, first to autonomy, then to amplification. These results raise the question of the possible role of cysteine proteinase proregions, of cysteine proteinases themselves and of inhibitors thereof in activated T lymphocytes; from a different point of view, they also show that some protease proregions may have evolved as autonomous modules.

Amino Acid Sequence↗