Papers by laurent boulanger
International audienceThe expression of POU5F1 is controlled by cis-regulatory elements located 5... more International audienceThe expression of POU5F1 is controlled by cis-regulatory elements located 5' upstream from the initiation start site. This regulatory region is highly conserved among species, and especially four conserved regions (CR1 to 4) have been identified. The minimal promoter is located in the CR1 region, while the proximal and distal enhancers involved in cell specific regulation of expression are located in CR2- 3 and CR4 regions respectively. In the mouse the two enhancer regions contribute differently to gene expression depending on the developmental stage of the embryo. POU5F1 repression of expression is induced by regulatory factors binding to the 5' upstream region but also by DNA and histone methylation. DNA methylation of POU5F1 has been mostly analyzed in in vitro derived stem cells. However, promotor DNA methylation levels have been shown to differ between embryonic stem cells and the "in embryo" counterparts they are derived from. We thus d...
International audienceThe POU5F1 gene encodes one of the "core" transcription factors n... more International audienceThe POU5F1 gene encodes one of the "core" transcription factors necessary to maintain pluripotency but very few data are available concerning the precise epigenetic regulation of its expression in early embryo. We analysed the progressive modifications of DNA methylation of POU5F1 upstream region in the different compartments of the developing blastocyst. Therefore we used the rabbit embryo as a model for most mammalian blastocysts, where contrarily to the mouse, epiblast differentiates in a plane embryonic disk at the surface of the conceptus and in direct contact with maternal environment. Embryos were micro dissected at Day4,5, and6. POU5F1 expression was quantified by RTqPCR. Methylation profile of four regions encompassing conserved cis-elements (Kobolak et al. 2009 BMC Mol. Biol.10 88.) was determined by bisulfite treatment, cloning and sequencing. POU5F1 is highly expressed in Day4 trophectoderm but significantly enriched in the inner cell mass...
BCAR4 is involved in [i]in vitro[/i] preimplantation development: investigating its role [i]in vi... more BCAR4 is involved in [i]in vitro[/i] preimplantation development: investigating its role [i]in vivo[/i] by genome efditing in rabbit. 2. Journées du GdR 3606 Repr
Frontiers in Cell and Developmental Biology
Male gametogenesis involves both mitotic divisions to amplify germ cell progenitors that graduall... more Male gametogenesis involves both mitotic divisions to amplify germ cell progenitors that gradually differentiate and meiotic divisions. Centrosomal regulation is essential for both types of divisions, with centrioles remaining tightly paired during the interphase. Here, we generated and characterized the phenotype of mutant mice devoid of Cep250/C-Nap1, a gene encoding for a docking protein for fibers linking centrioles, and characterized their phenotype. The Cep250-/- mice presented with no major defects, apart from male infertility due to a reduction in the spermatogonial pool and the meiotic blockade. Spermatogonial stem cells expressing Zbtb16 were not affected, whereas the differentiating spermatogonia were vastly lost. These cells displayed abnormal γH2AX-staining, accompanied by an increase in the apoptotic rate. The few germ cells that survived at this stage, entered the meiotic prophase I and were arrested at a pachytene-like stage, likely due to synapsis defects and the un...
International audienceThe expression of POU5F1 is controlled by cis-regulatory elements located 5... more International audienceThe expression of POU5F1 is controlled by cis-regulatory elements located 5' upstream from the initiation start site. This regulatory region is highly conserved among species, and especially four conserved regions (CR1 to 4) have been identified. The minimal promoter is located in the CR1 region, while the proximal and distal enhancers involved in cell specific regulation of expression are located in CR2- 3 and CR4 regions respectively. In the mouse the two enhancer regions contribute differently to gene expression depending on the developmental stage of the embryo. POU5F1 repression of expression is induced by regulatory factors binding to the 5' upstream region but also by DNA and histone methylation. DNA methylation of POU5F1 has been mostly analyzed in in vitro derived stem cells. However, promotor DNA methylation levels have been shown to differ between embryonic stem cells and the "in embryo" counterparts they are derived from. We thus d...
International audienceThe POU5F1 gene encodes one of the "core" transcription factors n... more International audienceThe POU5F1 gene encodes one of the "core" transcription factors necessary to maintain pluripotency but very few data are available concerning the precise epigenetic regulation of its expression in early embryo. We analysed the progressive modifications of DNA methylation of POU5F1 upstream region in the different compartments of the developing blastocyst. Therefore we used the rabbit embryo as a model for most mammalian blastocysts, where contrarily to the mouse, epiblast differentiates in a plane embryonic disk at the surface of the conceptus and in direct contact with maternal environment. Embryos were micro dissected at Day4,5, and6. POU5F1 expression was quantified by RTqPCR. Methylation profile of four regions encompassing conserved cis-elements (Kobolak et al. 2009 BMC Mol. Biol.10 88.) was determined by bisulfite treatment, cloning and sequencing. POU5F1 is highly expressed in Day4 trophectoderm but significantly enriched in the inner cell mass...
1. European Symposium on Sex Determination in Vertebrates, Mar 1, 2017
BCAR4 is involved in [i]in vitro[/i] preimplantation development: investigating its role [i]in vi... more BCAR4 is involved in [i]in vitro[/i] preimplantation development: investigating its role [i]in vivo[/i] by genome efditing in rabbit. 2. Journées du GdR 3606 Repr
1. European Symposium on Sex Determination in Vertebrates, Mar 1, 2017
Une meilleure comprehension de la reproduction des animaux domestiques depend d'une bonne con... more Une meilleure comprehension de la reproduction des animaux domestiques depend d'une bonne connaissance du trafic moleculaire existant entre les tissus maternels uterins et le conceptus. Des molecules complexes sont impliquees dans les interactions embryo-maternelles, parmi lesquelles des proteines et des mediateurs lipidiques jouent un role important pour l'implantation et le developpement de l'embryon. Chez certaines especes, des mediateurs lipidiques derives des lysophospholipides et des eicosanoides ont ete decrits comme acteurs impliques dans ces processus biologiques. Chez les ruminants, l'endometre synthetise de nombreux metabolites cyclooxygenes derives de l'acide arachidonique (AA), un acide gras polyinsature, issus des phospholipides membranaires de la cellule. L'AA peut egalement suivre d'autres voies metaboliques telles celle des Epoxygenases P450 ou encore celle des Lipoxygenases (LOX). Les travaux preliminaires au sein de notre laboratoire on...
National audienceWe have previously characterized BCAR4 (Breast Cancer Anti-estrogen Resistant 4)... more National audienceWe have previously characterized BCAR4 (Breast Cancer Anti-estrogen Resistant 4) as a gene preferentially expressed in human oocytes as compared to ovarian somatic cells or non-pathologic non-reproductive tissues. BCAR4 is conserved in primates and in various domestic species such as cow, pig, dog, horse or rabbit, but it is not found in the genome of rodents. This pattern coincides with a delayed major activation of the embryonic genome, i.e. after several cleavages. BCAR4 is also an oncogene overexpressed in a subset of breast tumors and other cancers. Altogether, the restricted expression, proliferative properties and phylogeny suggested that BCAR4 may be involved in early embryonic divisions.We have analyzed BCAR4 expression in the cow. While RNA is already transcribed in the oocyte of preovulatory follicles, protein synthesis is delayed until late maturation, peaks in early cleaving embryos, persists until the morula stage to become undetectable in blastocysts....
An Argentinian family with hereditary elliptocytosis (HE) associated with a shortened p-spectrin ... more An Argentinian family with hereditary elliptocytosis (HE) associated with a shortened p-spectrin (Sp) chain was studied. As with most of the other shortened Spp-chains that have been described, this variant, called SpTandi', has impaired ability to participate in Sp dimer self-association, has lost its ability to become phosphorylated, and is associated with the presence of increased amounts of the al 74-Kd fragment after partial tryptic digestion of Sp. The 3' ends of the p-Sp gene of affected patients were analyzed. cDNA was prepared by reverse transcription of peripheral blood mRNA and amplified by the polymerase chain reaction (PCR) using primers corresponding to sequences 400 bp apart on the cDNA, spanning the last three exons (X, Y, 2) of the p-Sp gene. Agarose gel electrophoresis of the cDNA amplification showed the presence of one band, the size of which was apparently the same as the band amplified from mRNA of a normal control. cDNA from one HE patient was subclone...
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Papers by laurent boulanger