Oligonucleotides Modified With Transplatin Derivatives: Fast and Efficient Metalloribozymes

When an oligonucleotide containing a 1,3-(G,G)-transplatin cross-link at a GNG site (N represents a C, T, A or U residue) is paired with its complementary strand, the intrastrand adduct rearranges into an interstrand cross-link, resulting in the covalent attachment of both strands. Here, we have studied the influence of the inert ligands of the platinum(II) complex and of the nucleotide residues in the vicinity of the adduct on the rearrangement reaction. Dramatic effects on the linkage isomerization rate could be 37℃. The results are analyzed in relation with the mechanism of rearrangement of the 1,3-intrastrand adducts into interstrand cross-links. The relevance of platinated oligonucleotides as potent and specific drugs is discussed

Spatio-temporal expression patterns of aurora kinases a, B, and C and cytoplasmic polyadenylation-element-binding protein in bovine oocytes during meiotic maturation.

International audienceMaturation of immature bovine oocytes requires cytoplasmic polyadenylation and synthesis of a number of proteins involved in meiotic progression and metaphase-II arrest. Aurora serine-threonine kinases--localized in centrosomes, chromosomes, and midbody--regulate chromosome segregation and cytokinesis in somatic cells. In frog and mouse oocytes, Aurora A regulates polyadenylation-dependent translation of several mRNAs such as MOS and CCNB1, presumably by phosphorylating CPEB, and Aurora B phosphorylates histone H3 during meiosis. We analyzed the expression of three Aurora kinase genes--AURKA, AURKB, and AURKC--in bovine oocytes during meiosis by reverse transcription followed by quantitative real-time PCR and immunodetection. Aurora A was the most abundant form in oocytes, both at mRNA and protein levels. AURKA protein progressively accumulated in the oocyte cytoplasm during antral follicle growth and in vitro maturation. AURKB associated with metaphase chromosomes. AURKB, AURKC, and Thr-phosphorylated AURKA were detected at a contractile ring/midbody during the first polar body extrusion. CPEB, localized in oocyte cytoplasm, was hyperphosphorylated during prophase/metaphase-I transition. Most CPEB degraded in metaphase-II oocytes and remnants remained localized in a contractile ring. Roscovitine, U0126, and metformin inhibited meiotic divisions; they all induced a decrease of CCNB1 and phospho-MAPK3/1 levels and prevented CPEB degradation. However, only metformin depleted AURKA. The Aurora kinase inhibitor VX680 at 100 nmol/L did not inhibit meiosis but led to multinuclear oocytes due to the failure of the polar body extrusion. Thus, in bovine oocyte meiosis, massive destruction of CPEB accompanies metaphase-I/II transition, and Aurora kinases participate in regulating segregation of the chromosomes, maintenance of metaphase-II, and formation of the first polar body

Tissue Resources for the Functional Annotation of Animal Genomes

In order to generate an atlas of the functional elements driving genome expression in domestic animals, the Functional Annotation of Animal Genome (FAANG) strategy was to sample many tissues from a few animals of different species, sexes, ages, and production stages. This article presents the collection of tissue samples for four species produced by two pilot projects, at INRAE (National Research Institute for Agriculture, Food and Environment) and the University of California, Davis. There were three mammals (cattle, goat, and pig) and one bird (chicken). It describes the metadata characterizing these reference sets (1) for animals with origin and selection history, physiological status, and environmental conditions; (2) for samples with collection site and tissue/cell processing; (3) for quality control; and (4) for storage and further distribution. Three sets are identified: set 1 comprises tissues for which collection can be standardized and for which representative aliquots can be easily distributed (liver, spleen, lung, heart, fat depot, skin, muscle, and peripheral blood mononuclear cells); set 2 comprises tissues requiring special protocols because of their cellular heterogeneity (brain, digestive tract, secretory organs, gonads and gametes, reproductive tract, immune tissues, cartilage); set 3 comprises specific cell preparations (immune cells, tracheal epithelial cells). Dedicated sampling protocols were established and uploaded in https://data.faang.org/protocol/samples. Specificities between mammals and chicken are described when relevant. A total of 73 different tissues or tissue sections were collected, and 21 are common to the four species. Having a common set of tissues will facilitate the transfer of knowledge within and between species and will contribute to decrease animal experimentation. Combining data on the same samples will facilitate data integration. Quality control was performed on some tissues with RNA extraction and RNA quality control. More than 5,000 samples have been stored with unique identifiers, and more than 4,000 were uploaded onto the Biosamples database, provided that standard ontologies were available to describe the sample. Many tissues have already been used to implement FAANG assays, with published results. All samples are available without restriction for further assays. The requesting procedure is described. Members of FAANG are encouraged to apply a range of molecular assays to characterize the functional status of collected samples and share their results, in line with the FAIR (Findable, Accessible, Interoperable, and Reusable) data principles

OVOGENAE2. La régulation de l'expression génique dans l'ovocyte, enjeu pour l'élevage bovin

National audienc

Ce que nous devons à notre mère : les ARN ovocytaires dans la compétence au développement de l'embryon

National audienc

Habilitation à Diriger des Recherches

Diplôme : HD

Transcriptome in bovine oocyte: general profile and marker genes

National audienc

Use of heterologous complementary DNA array screening to analyze bovine oocyte transcriptome and its evolution during in vitro maturation

International audienc

A profile of gene expression in bovine oocytes generated by heterospecific cDNA array screening

International audienc

Identification et caractérisation de gènes préférentiellement exprimés dans l'ovocyte bovin

Several oocyte-specific genes were shown to be essential for folliculogenesis and preimplantation embryo development in mouse. The aim of this thesis was to identify such genes in bovine. By RT-PCR, MATER, NALP9, ZARI, GDF9 and BMP15 genes were shown to be preferentially expressed in oocyte and transcription was not reactivated at the time of maternal to embryo transition. Full-length MATER and NALP9 cDNA were cloned. MATER protein was detected in oocytes from primary follicle onwards and in embryos until the blastocyst stage. In parallel, we performed suppressive subtraction hybridization between oocytes and somatic tissues. Macroarray hybridization revealed that 80% of EST were overexpressed fourfold in oocyte. By RT-PCR, 6 identified genes (including STELLA and SLBP2) and 8 novel EST were shown to be indeed preferentially expressed in oocyte and/or testis. These profiles suggest a role for the corresponding genes in gametogenesis and/or early embryonic development.Chez la souris, plusieurs gènes ovocyte-spécifiques sont essentiels pour la folliculogenèse ou le développement embryonnaire. L'objectif de la thèse était d'identifier de tels gènes chez le bovin. Par RT-PCR, nous avons montré que les gènes MATER, NALP9, ZARI, GDF9 et BMP15 sont préférentiellement exprimés dans l'ovocyte et qu'ils ne sont pas transcrits à la transition maternelle embryonnaire. La protéine MATER est détectée dans l'ovocyte dès le follicule primaire et dans l'embryon jusqu'au blastocyste. En parallèle, une banque soustraite d'EST prépondérantes dans l'ovocyte par rapport aux tissus somatiques a été générée par hybridation suppressive et soustractive. Plus de 80% des EST sont surexprimées dans l'ovocyte. L'expression préférentielle dans l'ovocyte et/ou le testicule de 6 gènes connus (dont STELLA, SLBP2) et 8 nouvelles EST a été confirmée par RT/PCR. Ces profils suggèrent que les gènes bovins étudiés jouent un rôle dans la gamétogenèse et/ou le développement précoce.TOURS-BU Sciences Pharmacie (372612104) / SudocSudocFranceF