Project description:Oocyte quality largely determines the embryo development after fertilization. High-quality oocyte requires the competence of both cytoplasm and nucleus. However, clinically, the treatment of developmentally competent oocytes was limited. Here, in order to improve the embryo development efficiency of developmentally incompetent oocytes, we performed spindle-chromosome complex (SCC) transfer between in vitro matured (IVM) and in vivo matured (IVO) oocytes of the non-human primate. We observed that the blastocyst rate of embryos derived by transferring the SCC of IVM (IVM-SCC) oocytes into enucleated IVO oocytes was comparable with that of embryos derived by IVO oocytes. After transferring the reconstructed embryos into the uterus of surrogate mothers, two live rhesus monkeys were obtained, indicating that the nuclei of IVM oocytes support both the pre-and post-implantation embryo development of non-human primates.
Project description:Expression data from prepubertal, peripubertal, and adult derived mouse oocytes, and from germinal vesicle (GV), in vivo matured, and in vitro matured mouse oocytes. Oocytes derived from prepubertal females, or oocytes matured in vitro, are less developmentally competent compared to adult derived, or in vivo matured, oocytes, indicated by decreased embryonic development. One potential mechanism for decreased developmental potetential in prepubertal or in vitro matured oocytes is inadequate or inappropriate RNA degradation during oocyte maturation (progression from GV to MII). To investigate mechanisms involved in establishing oocyte cytoplasmic maturation and developmental competence, Affymetrix GeneChip microarrays were used. Keywords: Oocyte developmental competence The study encompassed three experimental designs using female B6D2F1 mice: 1) In vitro matured oocytes were obtained from d20 (prepubertal), d26 (peripubertal), and 7-8 wk old (adult) mice; 2) in vivo and in vitro matured oocytes were obtained from d26 mice; and 3) GV, in vivo matured, and in vitro matured oocytes were obtained from 7-8 wk old mice. RNA was extracted from pools of 150 oocytes and hybridized onto the Affymetrix microarrays.
Project description:Expression data from prepubertal, peripubertal, and adult derived mouse oocytes, and from germinal vesicle (GV), in vivo matured, and in vitro matured mouse oocytes. Oocytes derived from prepubertal females, or oocytes matured in vitro, are less developmentally competent compared to adult derived, or in vivo matured, oocytes, indicated by decreased embryonic development. One potential mechanism for decreased developmental potetential in prepubertal or in vitro matured oocytes is inadequate or inappropriate RNA degradation during oocyte maturation (progression from GV to MII). To investigate mechanisms involved in establishing oocyte cytoplasmic maturation and developmental competence, Affymetrix GeneChip microarrays were used. Keywords: Oocyte developmental competence
Project description:Four groups of human oocytes from in vitro fertilization programme were analysed using microarrays: 1.) oocytes matured in vivo (retrieved as mature by ultrasound follicular aspiration but not fertilized after in vitro fertilization), 2.) oocytes matured in vitro in a conventional way (in a maturation medium with added gonadotropins FSH and HCG), 3.) oocytes matured in vitro by a new approach (in a maturation medium with added gonadotropins FSH and HCG, and in a co-culture with cumulus cells from mature oocytes of the same patient), and 4.) not matured oocytes which did not mature in spite of in vitro maturation procedure. Each group of oocytes consisted of three biological replicates with 10 oocytes per replicate therefore 12 oocyte samples and altogether 120 human oocytes were analyzed by microarrays.
Project description:In cattle, almost all fully grown vesicle stage oocytes (GV) have the ability to resume meisos, develop to Metaphase II stage (MII), support fertilization and progress through the early embryonic cycles in vitro. Yet without intensive selection, the majority fail to develop to the blastocyst stage. Using the Affymetrix Bovine Genome Array, global mRNA expression analysis of immature (GV) and in vitro matured (IVM) bovine oocytes was carried out to characterize the transcriptome of the bovine oocyte and to identify the key pathways associated with oocyte meiotic maturation and developmental potential. Immature and in vitro matured bovine oocytes were collected for RNA extraction and hybridization on Affymetrix GeneChip Bovine Genome array. Careful removal of cumulus and selection of oocytes was carried out under the stereo microscope in order to examine the actual cumulus-free temporal oocyte gene expression profiles. Immature oocytes at time 0 h and in vitro matured oocytes at 24 h were collected for analysis.
Project description:In cattle, almost all fully grown vesicle stage oocytes (GV) have the ability to resume meisos, develop to Metaphase II stage (MII), support fertilization and progress through the early embryonic cycles in vitro. Yet without intensive selection, the majority fail to develop to the blastocyst stage. Using the Affymetrix Bovine Genome Array, global mRNA expression analysis of immature (GV) and in vitro matured (IVM) bovine oocytes was carried out to characterize the transcriptome of the bovine oocyte and to identify the key pathways associated with oocyte meiotic maturation and developmental potential.
Project description:Cumulus cells, surrounding the oocyte, play a key role in the acquisition of oocyte competence to be fertilized and to sustain early embryo development. Cumulus cells contribute to oocyte development by metabolizing energy substrates such as glutathione that may protect the oocyte from oxidative stress damages. The aim of our study was to compare transcriptomics profiles of cumulus enclosed (CEO) and cumulus denuded (CDO) oocytes after in vitro maturation. Global transcriptional profiling was performed using cumulus enclosed and cumulus denuded oocytes after in vitro maturation. Matured oocytes were obtained after 22h of maturation with (CEO) or without (CDO) cumulus cells and four replicates of 25 oocytes were collected for RNA extraction. Gene expression analysis was performed by comparing CDO versus CEO oocytes that represents a total of 8 slides using a dye swap hybridisation protocol.
Project description:Single cell transcriptomic composition of in vivo matured (IVO) MII oocytes and maturation deficient (MD) oocytes discloses the aberrant expression level of spliceosomal proteins, accompanying with differential alternative splicing (DAS) events.
Project description:The oocyte forms a complex with their somatic cumulus cells within the follicle throughout the preovulatory maturation steps. Cumulus cells support their oocyte not only through mechanical protection but also with a close bidirectional exchange of metabolites. Analysis of the oocytes cumulus gives the opportunity to explore non-invasively oocytal well-being and quality. In vitro maturation (IVM) is the first rate-limiting step in in vitro embryo production. Analysis of protein expression in cumulus cells around this critical step helps to explore the impact of maturation conditions and to examine an influence on maturational competence of the oocyte. The goal of this study was the comparison of the cumulus proteome of oocytes with and without maturational competence matured under in vivo and in vitro conditions. Therefore twenty cumulus samples corresponding to single oocytes were analysed. Half of the samples were matured in vivo and the other half in vitro. For each maturation group, cumulus from oocytes matured successfully (SM; n=5) and failed to mature (FM; n=5) were analysed.
Project description:To elucidate some of the tools involved in early embryonic reprogramming, the levels of gene transcripts believed to be of importance to epigenetic modifications, and chromatin remodeling were detected by oligonucleotide microarrays in in vivo matured MII oocytes and compared with fully in vivo grown GV oocytes.