Project description:Purpose: In this study, we investigated the effect of microinjection on oocytes transcriptome changes through scrambled siRNA injection. Method: Scrambled siRNA injection followed by RNA-seq of single oocytes. Result:Our result showed 119 transcripts were differentially expressed of which 76 were down-regulated after scrambled siRNA injection.
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:The objective of the study was to analyze the impact of various lenght FSH withdrawal period (coasting) after the last FSH injection on transcriptome changes in in vivo bovine oocytes at the GV stage. Oocytes were collected from super-stimulated animals after 20, 44, 68 and 92 hours of coasting.
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:Profiles of H3K4me3, H3K27ac, H3K27me3 and H3K9me3 in bovine GV oocytes and preimplantation embryos, and the characterization of chromatin accessibility in bovine blastocyst, inner cell mass and trophectoderm.
Project description:The present study mainly aimed to investigate the effect of vitrification temperature (VT) and cryoprotective agent concentrations (CPAs) on the mRNA transcriptome of bovine immature oocytes (BIOs). Cumulus oocyte complexes (COCs) were randomly divided into the following five groups: fresh oocytes (control), oocytes vitrified in liquid helium (LHe; -269℃) with 5.6 M CPAs (LHe 5.6 M), oocytes vitrified in LHe with 6.6 M CPAs (LHe 6.6 M), oocytes vitrified in liquid nitrogen (LN; -196℃) with 5.6 M CPAs (LN 5.6 M), and oocytes vitrified in LN with 6.6 M CPAs (LN 6.6 M). mRNA transcriptomes of each sample were analyzed by Smart-seq4, and the differentially expressed genes (DGEs) were detected by edgeR (p≤0.05; fold-change≥2). Compared with the control group, 505 DGEs were detected with 342 up-regulated and 163 down-regulated genes in LHe 5.6 M; 609 DGEs were detected with 493 up-regulated and 116 down-regulated gene in LHe 6.6 M; 218 DGEs were determined with 101 up-regulated and 117 down-regulated genes in LN 5.6 M; and 221 DGEs were detected with 104 up-regulated and 117 down-regulated genes in LN 6.6 M. LHe vitrification affected the mRNA transcriptome of vitrified BIOs mainly by up-regulating gene expression. Reduced CPAs (5.6 M) decreased the effect of vitrification on mRNA transcriptome when LHe vitrification was used. Among all the DGEs closely related to bovine immature oocytes, the genes possibly related to VT were ND2, MPV17L2, PIF1, LPIN1, IMP3, BRD1, DCTN3, DERA, ATP7B, NEK5, HVCN1 and MARK2. The gene that may be associated with CPAs is CC2D2A. Genes that may be affected by both VT and CPAs were PGK1, SLC7A3, FITM2, NPM3, ISCU, CWC15 and PSAP. DERA was up-regulated when reduced VT (-269 °C) was used, which may have contributed to the recovery and stress prevention of vitrified oocyte.
Project description:The objective of the study was to analyze the effect of a GnRH antagonist used during the FSH withdrawal period (coasting) on transcriptome changes in in vivo bovine oocytes at the GV stage. Oocytes were collected from super-stimulated animals after a coasting duration of 68hrs (optimal condition, control) and also from the same animal who received the GnRH antagonist (treated) during the whole coasting period.
Project description:ATAC sequencing of bovine oocytes and early embryos revealed a genome-wide map of accessible chromatin of bovine early embryo development, highlighting the critical features of chromatin landscape and epigenetic reprogramming during bovine preimplantation embryo development.
Project description:Pyruvate, the end-product of glycolysis in aerobic conditions, is converted into acetyl-CoA inside the mitochondria of oocytes as a master fuel input for the tricarboxylic acid (TCA) cycle. The citrate generated in the TCA cycle can be directed to the cytoplasm and converted back to acetyl-CoA, being driven to lipid synthesis or, alternatively, being used as the substrate for histones acetylation. This work aimed to verify the impact of pyruvate metabolism on the dynamics of lysine 9 histone 3 acetylation (H3K9ac) and RNA transcription in bovine oocytes during in vitro maturation (IVM). Bovine cumulus-oocyte complexes were subjected to IVM for 24 h considering three experimental groups: Control [IVM medium], sodium dichloroacetate [DCA, a stimulator of pyruvate oxidation into acetyl-CoA] or sodium iodoacetate [IA, a glycolysis inhibitor]. Our results show that both treatments change the metabolic profile of oocytes, stimulating the use of lipids for energy metabolism in the gamete. This leads to changes during IVM in the dynamics of H3K9ac, consequently impacting the oocyte transcriptional profile. A total of 148 and 356 differentially expressed genes were identified in DCA and IA oocyte groups, respectively, when compared to the control group. In summary, our results indicate that changes in the pyruvate metabolism induce the activation of metabolic pathways, such as lipid metabolism, and these metabolic alterations alter acetyl-CoA availability and H3K9ac levels at 24 h of IVM, consequently impacting the mRNA content of bovine oocytes.