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F Le Provost

Publications and source records attributed to F Le Provost.

8 recordsLinked to original sources
PubMed2007

Goat PRND expression pattern suggests its involvement in early sex differentiation.

Expression of the goat prion protein gene locus was assessed by reverse transcriptase-polymerase chain reaction on testes and ovaries at various developmental stages. A weak and stochastic expression of the PRNP and PRNT genes was observed. For PRNT, it is consistent with the detected deletions of two single nucleotides within its open reading frame in ruminant genes. PRND was expressed in both tissues at all stages. Whereas its expression is constant in the ovaries, it increases in testes between 36 and 46 days postcoitum (dpc) and remains high thereafter. In testes, Doppel was found in the nucleus of germinal cells and in the cytoplasm of Leydig cells at 44 dpc. It was detected in the cytoplasm of Leydig cells and of some Sertoli and germinal cells at 62 dpc. In the ovaries, it was observed in the nucleus of germinal cells at 44 dpc and mainly in their cytoplasm at 62 dpc. This expression pattern was shown to parallel that of C-kit and suggests Doppel involvement in early testis differentiation.

Amino Acid Sequence↗
PubMed2005

A cDNA macroarray resource for gene expression profiling in ruminant tissues involved in reproduction and production (milk and beef) traits.

cDNA arrays have proven to be useful tools to screen gene expression in many animal species including livestock species. A collaborative program was launched to construct a ruminant cDNA collection, representative of three tissues: Muscle, Embryo and Mammary gland, named MEM. This collection gathers clones mainly arising from 3 non-normalised cDNA libraries: a directed bovine muscle library, a 14-day-old bovine embryo library and a goat lactating mammary library. It is made up of 1896 clones (637 muscle, 882 embryo and 377 mammary cDNAs), selected after sequencing and bioinformatic analyses. Amplification products yielded from these clones as well as controls were printed onto Nylon membranes to generate macroarrays. Hybridisation with relevant cDNA targets allowed checking the location of about 50 cDNAs and the specificity of each sub-set of the repertoire. Macroarrays were hybridised with radiolabelled cDNA complex targets from five different tissues (muscle, embryo, mammary gland, adipose tissue and oocyte). Both somatic and germinal complex targets gave valid hybridisation signals with 45 to 80% of the printed probes. This specific cDNA collection now provides a powerful tool for transcriptomic studies with the ultimate objective to better understand physiological and metabolic functions in ruminants. It will be subsequently included into a forthcoming larger collection.

Animals↗
PubMed1997

Rat prolactin synthesis by lactating mammary epithelial cells.

It has previously been suggested that the mammary cell could produce prolactin (PRL). This hypothesis was investigated by incubation with [35S]methionine-cysteine followed by SDS-PAGE, immunoblotting and autoradiography of immunoprecipitated PRL, and by electron microscopic analysis after incubation without or with cycloheximide. Immunoreactive 14-, 23-, 25-, 32- and 36-kDa PRL forms were radioactive. By two-dimensional electrophoresis analysis, immunoreactive and radioactive spots, of about 25 kDa and high molecular weight, were also detected. After incubation of mammary epithelial cells with cycloheximide, immunogold electron microscopy showed a drastic decrease of labelling in organelles involved in synthesis and secretion, compared to those incubated in control medium. These results make it possible to conclude that lactating mammary tissue is able to synthesize PRL.

Animals↗
PubMed1996

A survey of the goat genome transcribed in the lactating mammary gland.

To fulfill its primary function, which is to synthesize milk during the course of lactation, the mammary gland requires efficient transcriptional, translational, and secretory machineries involving multiple genes among which promising candidates underlying the genetic variation of milk production have to be found. With the aim of providing a first transcriptional profile of lactating mammary tissue, a non-normalized cDNA library has been constructed from the udder of a lactating goat. After having discarded cDNA clones encoding the major milk proteins the rapid characterization of genes expressed in this tissue, by automated partial cDNA sequencing, was used to analyze a total of 435 cDNA clones. Examination of the Expressed Sequence Tags (ESTs) for similarities with sequence databases identified 234 cDNAs corresponding to 140 unique genes or proteins. Eighty-three clones, not similar to any current database entries, representing 77 novel sequences unrelated to previously described genes, were thus identified. Tissue specificity and relative abundance of 18 of these 77 unidentified clones were examined by dot blot and RT-PCR experiments. Sequence data were subsequently used to assign six genes of unknown localization in the bovine genome, to synteny groups by use of bovine-hamster cell hybrids and PCR.

Animals↗
PubMed1994

Characterization of the goat lactoferrin cDNA: assignment of the relevant locus to bovine U12 synteny group.

Lactoferrin (LTF), which is the major iron-binding protein in milk and physiological fluids, belongs to the transferrin family. We report here the sequence of a caprine LTF cDNA, 2411 bp in length, encoding the pre-protein (709 amino acid residues). Sequence comparisons reveal that structural features, including iron-binding sites, cysteine residues involved in disulphide bonds are remarkably conserved between LTF proteins from various species. Of the 5 potential glycosylation sites identified, only one site appears to be conserved between artiodactyls, rodents and humans. Using a somatic cell hybrid panel, the LTF locus was assigned to the bovine U12 syntenic group. This assignment and the localization of the LTF gene on bovine chromosome 22 (BTA 22) by Schwerin et al. (1) using fluorescent in situ hybridization achieves an additional analogy between a synteny group and a chromosome in cattle. Since serum transferrin (STF) had been previously mapped on BTA 1, in cattle LTF and STF loci are not localized on the same chromosome, conversely to the situation observed in humans (HSA 3) and mice (MMU 9).

Amino Acid Sequence↗
PubMed1994

Prolactin gene expression in ovine and caprine mammary gland.

The presence of prolactin (PRL) mRNA in the mammary gland of lactating goats and sheep was demonstrated by Northern analysis and RT-PCR. This provides evidence that the PRL gene is transcribed in this tissue. This ectopic expression is not restricted to the lactational period, as PRL transcripts were also found during the last third of pregnancy. Comparison of mammary and pituitary PRL mRNAs showed that they are similar in size but less abundant in mammary gland. In addition, an 847-bp cDNA fragment amplified from mammary retrotranscripts, containing the entire coding region and the major part of the 5' and 3' untranslated regions (UTRs), was found to be identical in sequence to its pituitary counterpart. Primer extension analysis, performed to obtain further information on the structure of the mammary PRL mRNA, has shown that the 5' UTR is 56 nucleotides (nt) long for both species. This is comparable with the size (53 nt) found using the caprine pituitary RNA as template. These results strongly suggest that the PRL gene is not transcribed from a different promoter in mammary gland, as has been demonstrated for placental and lymphocyte cells, but is more likely transcribed from the pituitary-specific promoter. Finally, the presence of PRL mRNA in polysomal fractions suggests that PRL is synthesized in mammary cells.

Amino Acid Sequence↗
PubMedDate not supplied

Cytogenetic mapping of 25 goat mammary gland Expressed Sequence Tags (ESTs).

Today, there is a shift towards a positional candidate approach in the molecular identification of genes. This study reports on an Expressed Sequence Tags (ESTs) mapping initiative in goats, based on sequence information gathered from a previous mammary gland cDNA systematic sequencing project. A total of 25 novel genes was localised cytogenetically on 16 goat chromosomes. Six of these ESTs were found to map to cattle milk QTL regions. These results made it possible to assess the use of ESTs as a shortcut to the molecular identification of some QTLs and as a valuable tool for comparative mapping.

Journal Article↗