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F Hatey

Publications and source records attributed to F Hatey.

At least 19 recordsLinked to original sources
PubMed2006

Identification of differential gene expression in in vitro FSH treated pig granulosa cells using suppression subtractive hybridization.

FSH, which binds to specific receptors on granulosa cells in mammals, plays a key role in folliculogenesis. Its biological activity involves stimulation of intercellular communication and upregulation of steroidogenesis, but the entire spectrum of the genes regulated by FSH has yet to be fully characterized. In order to find new regulated transcripts, however rare, we have used a Suppression Subtractive Hybridization approach (SSH) on pig granulosa cells in primary culture treated or not with FSH. Two SSH libraries were generated and 76 clones were sequenced after selection by differential screening. Sixty four different sequences were identified, including 3 novel sequences. Experiments demonstrated the presence of 25 regulated transcripts.A gene ontology analysis of these 25 genes revealed (1) catalytic; (2) transport; (3) signal transducer; (4) binding; (5) anti-oxidant and (6) structural activities. These findings may deepen our understanding of FSH's effects. Particularly, they suggest that FSH is involved in the modulation of peroxidase activity and remodelling of chromatin.

Animals↗
PubMed2001

A novel method to isolate the common fraction of two DNA samples: hybrid specific amplification (HSA).

Hybrid specific amplification (HSA) is a novel simple method elaborated in order to isolate the common fraction of two DNA samples while avoiding the background due to repeated sequences. The method is based on the suppressive PCR principle, associated with a Cot1 pre-hybridization step. In recent work we demonstrated that hyperprolificity observed in Booroola ewes is associated with a mutation in the bone morphogenetic protein receptor IB gene (BMPR-IB). We applied HSA between ovarian cDNA and DNA from four BAC clones containing BMPR-IB in order to test for the presence of other genes expressed in ovary and to isolate additional BMPR-IB exon sequences. Of the 460 clones obtained, none contained repeated sequences. We successfully obtained 37 clones representing the major part of BMPR-IB coding sequence, together with 5'- and 3'-UTR sequences. Here we have successfully applied HSA to a particular tissue, but it should be possible to trap the common fraction of two DNA samples, whatever their nature.

Animals↗
PubMed2000

IMpRH server: an RH mapping server available on the Web.

SUMMARY: The INRA-Minnesota Porcine Radiation Hybrid (IMpRH) Server provides both a mapping tool (IMpRH mapping tool) and a database (IMpRH database) of officially submitted results. The mapping tool permits the mapping of a new marker relatively to markers previously mapped on the IMpRH panel. The IMpRH database is the official database for submission of new results and queries. The database not only permits the sharing of public data but also semi-private and private data.

Animals↗
PubMed1998

Characterization of FSH-regulated genes isolated by mRNA differential display from pig ovarian granulosa cells.

The present authors have isolated FSH-regulated genes from primary granulosa cell cultures with or without Follicle Stimulating Hormone (FSH) treatment using mRNA differential display. mRNA differential display consists of amplification of partial sequences of cDNAs (150-400 bp) corresponding to 3' ends of cellular messenger RNAs, and thus, generates 3' expressed sequence tags (3' ESTs). Five thousand cDNA bands were examined, among which the present authors have isolated and sequenced 16 different FSH-regulated products. These sequences were compared with those available in databases. Three of the sequences showed similarity to identified genes from other species (bovine NADH dehydrogenase subunit 4, Xenopus chromosome sequence-associated polypeptide E and transformation-sensitive protein IEF SSP) and four others with human ESTs. Regulation of the corresponding genes has been checked by RT-PCR since most of these are expressed at a low level. FSH-regulation was confirmed for 12 mRNAs (four down- and eight up-regulated). The present authors have also mapped 12 of these ESTs on porcine chromosomes regions using a somatic cell hybrid panel.

Animals↗
PubMed1997

Expression of SKP1 mRNA and protein in rat brain during postnatal development.

We previously isolated the cell cycle element SKP1 as a candidate plasticity gene in the rat visual cortex. Here, we studied the expression and localization of SKP1 mRNA and protein in rat brain. We found a high level of expression for the SKP1 gene in the cortex at different postnatal ages. SKP1 mRNA levels remained stable from P2 (postnatal day 2) to adulthood. SKP1 mRNA expression was also detected in several other brain areas. Skp1p (SKP1 protein) immunohistochemistry showed nuclear staining in a large majority of neurones. The pyramidal cells in the hippocampus, as well as cortical cells were stained. The presence of Skp1p in post-mitotic neurones suggests that this protein is involved in processes other than the cell cycles other target proteins and functions in neurones are currently under investigation.

Animals↗
PubMed1997

A first catalog of genes involved in pig ovarian follicular differentiation.

As a first step toward the characterization of genetic expression in pig ovaries, we have selected 238 clones by differential hybridization from a pig granulosa cell cDNA library, using probes prepared from RNA extracted from either untreated or FSH-treated cells and, in order to generate expressed sequence tags (ESTs), we have performed 3' and 5' single-pass sequencing of these clones. Sequences of the 3' end of the 167 clones that produced informative sequence data were first compared with each other, revealing a redundancy level of 21%. Sequences from the 136 unique clones were analyzed for similarities with sequence data included in Genbank and EMBL databases. Among these unique clones, 54 (40%) matched significantly with sequences from either Genbank of EMBL: 4 with known genes in pig, 35 matched with previously reported human genes, and 15 with other mammalian genes. Eighty-two clones (60%) showed no significant match with any gene or DNA sequence in the Genbank and EMBL databases and thus may represent new pig transcripts.

Animals↗
PubMed1996

Expression of messenger ribonucleic acids of insulin-like growth factor binding protein-2, -4, and -5 in the ovine ovary: localization and changes during growth and atresia of antral follicles.

In the sheep as in many mammalian species, growth and atresia of antral follicles are characterized, respectively, by a decrease and a high increase in the intrafollicular levels of insulin-like growth factor binding proteins of less than 40 kDa (IGFBPs < 40 kDa), mainly IGFBP-2, -4, and -5. The objective of this study was to investigate whether such changes are associated with changes in follicular expression of the corresponding mRNA. For this purpose, ovaries were recovered from ewes slaughtered at the end of follicular phase (i.e., 30 h after progestagen sponge removal; control ewes) or at 24 h, 36 h or 72 h after hypophysectomy (hypox) performed 30 h after sponge removal. The expression of mRNA of IGFBPs of less than 40 kDa (IGFBPs < 40 kDa mRNA) was studied in ovine antral follicles from control and hypox ewes by in situ hybridization using [35S]-labeled human IGFBP-2, -4, and -5 cRNA as probes. In control ewes, IGFBP-2 mRNA was mainly expressed in granulosa as a gradient in healthy follicles, the expression being higher in granulosa cells close to the basal membrane than in granulosa cells bordering the antrum and within the cumulus. The level of IGFBP-2 mRNA was lower both in granulosa cells close to the basal membrane and in those bordering the antrum from small follicles than in the corresponding compartments of granulosa cells from large healthy follicles (p < 0.05). In healthy follicles, IGFBP-4 and -5 mRNA were mainly expressed in thecal cells. No change in level of IGFBP-4 mRNA was observed between small and large follicles, whereas the level of IGFBP-5 mRNA tended to be lower in thecal cells from large compared to small follicles (p = 0.055). In atretic follicles, expression of IGFBPs < 40 kDa mRNA strongly increased in granulosa (IGFBP-2 and -5, p < 0.01) and in thecal cells (IGFBP-2 and -4, p < 0.01). In hypox ewes, the chronology of changes in expression of follicular IGFBPs < 40 kDa mRNA and in intrafollicular levels of the corresponding proteins was studied during atresia of large antral follicles. Early atresia of large follicles was associated with a strong decrease in intrafollicular estradiol levels (p < 0.001); an increase in intrafollicular levels of IGFBP-2, -4, and -5 (p < 0.001) an increase in both IGFBP-2 (p < 0.001) and -5 (p < 0.01) mRNA expression in granulosa and thecal cells; but no changed in IGFBP-4 mRNA expression. Late atresia of large follicles was associated with a further decrease in intrafollicular estradiol levels (p < 0.01); a further increase in intrafollicular levels of IGFBP-2, -4, and -5 (p < 0.001); an increase in IGFBP-4 (p < 0.01) and -5 (p < 0.05) mRNA expression in theca and granulosa, respectively; a decrease in IGFBP-5 mRNA expression in theca (p < 0.05); but no further increase in IGFBP-2 mRNA expression. Overall, these data suggest that the decrease and the increase in expression of mRNA of follicular IGFBPs < 40 kDa during follicular growth and atresia, respectively, are involved in the decrease and the increase in intrafollicular levels of the corresponding proteins. Moreover, the increases in expression of follicular IGFBPs < 40 kDa during atresia of large follicles in hypophysectomized ewes followed a specific time course, the increase in IGFBP-2 and -5 mRNA expression being early than the increase in IGFBP-4 mRNA expression.

Animals↗
PubMed1995

Protein kinase C inhibition of in vitro FSH-induced differentiation in pig granulosa cells.

In granulosa cells, growth factor IGF I plays a major role in both growth and differentiation, acting through an autocrine/paracrine mechanism, and its production is regulated by FSH, via cyclic AMP (cAMP). As protein kinase C is also involved in granulosa cell function, we investigated the possibility that its activation could balance the positive effects of FSH. Using pig granulosa cells cultured in vitro, we studied the effects of protein kinase C activation by tetradecanoylphorbol acetate (TPA) on IGF I mRNA level. We also checked morphological modifications, cAMP production and steroidogenesis at the P450 side chain cleavage mRNA and progesterone levels. Our data demonstrate that protein kinase C activation antagonizes the in vitro FSH-induced differentiation, particularly morphological modifications and accumulation of IGF I mRNA. These inhibitory effects on FSH responses suggest that there could be a balance between protein kinase A and protein kinase C pathways in regulating differentiation in pig granulosa cells.

Animals↗
PubMed1992

Gonadotropins induce accumulation of insulin-like growth factor I mRNA in pig granulosa cells in vitro.

Pig granulosa cells have been shown to synthesize insulin-like growth factor (IGF) I peptide in vitro, and this expression is regulated by gonadotropins via the cAMP pathway. By hybridizing an IGF I cDNA probe with total RNA isolated from pig granulosa cells cultured in vitro, we show that these cells contain two IGF I transcripts of about 0.9 kb and 9 kb in size. Treatment of the cells with gonadotropins (follicle-stimulating hormone, luteinizing hormone) or cAMP agonists (dibutyryl-cAMP, forskolin) induces an accumulation of the transcripts which can be abolished by transcriptional inhibitors, but not by translational inhibitors. We thus provide new evidence that pig granulosa cells are a site of IGF I synthesis, and we conclude that (1) gonadotropins increase IGF I mRNA levels; (2) the accumulation of IGF I mRNA results from an increased transcription; (3) the stimulation of IGF I gene transcription does not require ongoing protein synthesis; (4) these effects of follicle-stimulating hormone can be mimicked by cAMP agonists.

Animals↗
PubMed1981

Plasma dopamine-beta-hydroxylase and platelet monoamine oxidase activities in pigs with different susceptibility to the malignant hyperthermia syndrome by halothane.

Plasma DBH and platelet MAO activities were measured by radioenzymatic assay in 10 Large-White and 20 Piétrain pigs 9 to 11 weeks old. Piétrain pigs within the same litter, challenged by halothane, were classified as malignant hyperthermia (MH) susceptible or not according to their reaction. The Large-White pig strain was not susceptible to MH. Plasma DBH activity did not differ according to strain or to MH susceptibility. Platelet MAO was lower in Large-White pigs but was not affected by MH susceptibility in Piétrain pigs. The results do not confirm any nervous differences in MH-susceptible pigs.

Animals↗
PubMed1979

Protein synthesis inhibition in rat liver by the mycotoxin patulin.

Patulin, a carcinogenic mycotoxin, inhibits in vivo and in vitro protein synthesis in rat liver. The in vivo inhibition culminates 5 h after toxin administration and reaches a maximum of 65% with regard to control values; a breakdown of polysomes is associated with the translational blockage. However in in vitro systems, the cellular fractions obtained from patulin-treated rats appear equally as active in protein synthesizing ability and as sensitive to the toxin action as those prepared from control animals. The in vitro inhibition by patulin is dose related. The postmitochondrial system is less sensitive than that functioning with isolated polysomes and pH 5 enzyme. This difference might be due to the presence of soluble factor(s) that counteract patulin action. We propose that the inhibition of protein synthesis by patulin may result from an interaction of the drug with active SH groups at the membrane level (amino acid transport, ion equilibrium) and/or at the cytoplasmic level (enzymes and factors involved in the translational process).

Amino Acids↗
PubMed1977

[Effect of patulin of RNA and protein synthesis in vitro].

Patulin, a mycotoxin isolated from cultures of Byssochlamis nivea, alters the transcriptional and translational processes. Using cell-free systems derived from procaryotic and mammalian cells, we have studied the mechanism of the mycotoxin-induced inhibition of in vitro RNA and protein syntheses.

Animals↗
PubMed1977

[Short term toxicity of ochratoxin A: some biochemical lesions in the rat (author's transl)].

The blood serum level of total proteins, urea, total lipids, cholesterol and glucose, and the excretion of nitrogen in the urine were estimated in control or treated rats. Male adult rats were given the toxin per os (0, 0.5, 1 or 2 mg/kg) during 10 days. An increase in the urinary volume was observed, with a decrease in the total nitrogen concentration. Blood total proteins and urea levels were higher than in control animals but total lipids and cholesterol levels dropped. Blood glucose concentration remained unaffected. These effects were evident even for the lowest dose and their intensity increased with the amount of toxin given to the animals. Statistical analysis showed significant differences between the results obtained in control animals and those obtained in animals treated with either 2 mg/kg or--except for blood urea--1 mg/kg.

Animals↗