Project description:During the perinatal period, unique metabolic adaptations support energetic requirements for rapid growth. To gain insight into perinatal adaptations, quantitative proteomics were performed comparing the livers of yorkshire pigs at postnatal day seven and adult. These data revealed differences in the metabolic control of liver function including significant changes in lipid and carbohydrate metabolic pathways. Newborn livers showed an enrichment of proteins in lipid catabolism and gluconeogenesis concomitant with elevated liver carnitine and acylcarnitines levels. Sugar kinases were some of the most dramatically differentially enriched proteins comparing neonatal and adult pigs including galactokinase 1 (Galk1), ketohexokinase (KHK), hexokinase 1 (HK1) and hexokinase 4 (GCK). Interestingly, hexokinase domain containing 1 (HKDC1), an enigmatic fifth hexokinase associated with glucose disturbances in pregnant women was highly enriched in the liver during the prenatal and perinatal periods and continuously declined throughout postnatal development in pigs and mice. These changes were confirmed via Western blot and mRNA expression. These data provide new insights into the developmental and metabolic adaptations in the liver during the transition from the perinatal period to adulthood in multiple mammalian species.
Project description:Zygotic genome activation (ZGA) occurs at the mid-blastula transition (MBT) in zebrafish and is a period of chromatin remodeling. Genome-scale gametic demethylation and remethylation occurs after fertilization, during blastula stages, but how ZGA relates to promoter DNA methylation states is unknown. Using methylated DNA immunoprecipitation coupled to high-density microarray hybridization (MeDIP-ChIP), we characterize genome-wide promoter DNA methylation dynamics before, during and after ZGA onset, in relation changes in post-translational histone modification and gene expression (Series GSE22830). A Kolmogorov-Smirnov (KS) test was applied with P <= 0.01 to identify methylation peaks. MeDIP-chip experiments were performed on24 hpf zebrafish embryos and sperm. Samples were lysed and proteins digested by proteinase k treatment. DNA was extracted with phenol-chloroform-isoamylalcohol and ethanol precipitation. The DNA was RNAse treated and sonicated to fragment lengths between 300-1000 bp. From each stage, duplicate immuneoprecipitations were performed using anti-5-methylcytosine antibody (10 ng/M-BM-5l; Mab-006-100; Diagenode) coupled to Dynabeads M-280 sheep anti-mouse IgG (Invitrogen). MeDIP and input DNA (150 ng each) were amplified (WGA-2; Sigma-Aldrich), cleaned up, eluted and processed for array hybridization. MeDIP and input DNA were labeled and co-hybridized onto the Nimbegen promoter arrays. The array covers 15 kb of upstream regulatory sequence and 5 kb downstream of the TSS of all zebrafish genes. A Kolmogorov-Smirnov (KS) test was applied with P <= 0.01 to identify methylation peaks.
Project description:Background: It is postulated that the developmental defects frequently observed in somatic clones arise from inappropriate reprogramming of the donor epigenome by the oocyte. We used cattle clones as a model to investigate the long-term effects of nuclear reprogramming on both DNA methylation and the phenotype of a differentiated organ, the liver. Pathological perinatal clones and apparently normal adult clones, both produced within one decade, were studied, together with age-matched controls. Results: Using MeDIP-chip, we identified differentially methylated regions (DMRs) in gene promoters displaying variations according to age and to the clone status of the animals. Strikingly, whereas adult clones did not differ significantly from adult controls, perinatal clones showed a demethylation at DMRs inconsistent with their chronological age. Pathological features were found in the liver of perinatal clones only, with histological lesions and modifications to both histomorphometrical and metabolic parameters. The integration of DMRs with phenotypic datasets led to the identification of epigenetic alterations correlated to phenotypic abnormalities in perinatal clones. Genes important to the antioxidant response and energy metabolism were targeted by these alterations. For at least one DMR, the aberrant methylation profile in perinatal clones was associated with altered gene expression. Conclusions: The liver defects encountered in pathological perinatal clones could be associated to the aberrant age of DNA methylation, at genes indicating potential deficits in oxidative metabolism. We propose that epigenetic ageing is an adaptation to the excessive oxidative stress induced by reprogramming that the pathological clones were not able to counteract during subsequent developmental stages.
Project description:This trial was undertaken to examine the perhipheral cellular and antibody response of cattle following infestation with the cattle tick, Rhipicephalus microplus. The information from the Affymetrix gene expression data is used to complement other measurements of immune function such as cellular subset composition and antibody response in cattle of high (Brahman) and low (Holstein-Friesian) resistance to the cattle tick. Experiment Overall Design: RNA was extracted from white blood cells during a period of successive, heavy infestations with R. microplus. RNA samples from 3 Holstein-Friesian and 3 Brahman animals were analysed on individual slides.
Project description:Pro-spermatogonia (SG) serve as the gateway to spermatogenesis. Using single-cell RNA sequencing (RNAseq), we studied the development of ProSG, their SG descendants, and testicular somatic cells, during the perinatal period in mice. We identified both gene and protein markers for 3 temporally distinct ProSG cell subsets, including a migratory cell population with a distinct transcriptome from the previously defined T1- and T2-ProSG stages. This intermediate (I)-ProSG subset translocates from the center of seminiferous tubules to the spermatogonial stem cell (SSC) “niche” in its periphery soon after birth. We identified 3 undifferentiated SG subsets at postnatal day 7, each of which express distinct genes, including transcription factor and signaling genes. Two of these subsets have the characteristics of newly emergent SSCs. We also molecularly defined the development of Sertoli, Leydig, and peritubular myoid cells during the perinatal period, allowing us to identify candidate signaling pathways acting between somatic and germ cells in a stage-specific manner during the perinatal period. Our study provides a rich resource for those investigating testicular germ and somatic cell developmental during the perinatal period.
Project description:Tet enzymes (Tet1/2/3) convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). Tet1 and Tet2 mediate 5hmC generation in mouse embryonic stem cells (ESCs) and various embryonic and adult tissues. To investigate the effects of combined deficiency of Tet1 and Tet2 on pluripotency and development, we have generated Tet1 and Tet2 double knockout (DKO) ESCs and mice. DKO ESCs were depleted of 5hmC, but remained pluripotent with subtle defects in differentiation and changes in gene expression. Double mutant embryos and chimeras exhibited mid-gestation defects and postnatal DKO mice displayed partially penetrant neonatal lethality and stochastic perturbation of imprinting. Viable DKO animals developed normally to adulthood but had reduced 5hmC level, increased 5mC level and lacked 5hmC in germ cells. Nevertheless, DKO mice of both sexes were fertile with females having smaller ovaries and reduced fertility. Our data suggest that both Tet1 and Tet2 contribute to 5hmC levels during development. Their combined loss does not block differentiation and embryogenesis, but leads to partially penetrant embryonic and perinatal abnormalities and compromised viability. Moreover, the presence of substantial levels of 5hmC in DKO embryos and adult mice suggests a significant contribution of Tet3 in hydroxylation of 5mC during development. Methylation patterns in tissue samples from a series of wt and Tet1/Tet2 DKO embryos, neonates and adults were generated using methylated DNA immunoprecipitation with antibodies against 5mC (MeDIP) and 5hmC (hMeDIP) followed by deep sequencing.
Project description:To investigate the differences in the epigenetic modification of somatic cloned cattle from different types of donors after reprogramming and differentiation,we established Six cell lines of cloned cattle from different donor nuclei (three strains derived from fetal fibroblasts, numbered FFB1, FFB2, and FFB3, and another three strains derived from fetal oviduct epithelial cells, numbered FOV1, FOV2, and FOV3)
Project description:Early life environmental exposure, particularly during perinatal period, can have a lifelong impact on organismal development and physiology. The biological rationale for this phenomenon is to promote physiological adaptation to the anticipated environment based on early life experience. However, perinatal exposure to adverse environments can also be associated with adult-onset disorders. Multiple environmental stressors induce glucocorticoids, which prompted us to investigate their role in developmental programming. Here, we report that perinatal glucocorticoid exposure had long-term consequences and resulted in diminished CD8 T cell response in adulthood and impaired control of tumor growth and bacterial infection. We found that perinatal glucocorticoid exposure resulted in persistent alteration of the hypothalamic-pituitaryadrenal (HPA) axis. Consequently, the level of the hormone in adults was significantly reduced, resulting in decreased CD8 T cell function. Our study thus demonstrates that perinatal stress can have long-term consequences on CD8 T cell immunity by altering HPA axis activity.
Project description:Early life environmental exposure, particularly during perinatal period, can have a lifelong impact on organismal development and physiology. The biological rationale for this phenomenon is to promote physiological adaptation to the anticipated environment based on early life experience. However, perinatal exposure to adverse environments can also be associated with adult-onset disorders. Multiple environmental stressors induce glucocorticoids, which prompted us to investigate their role in developmental programming. Here, we report that perinatal glucocorticoid exposure had long-term consequences and resulted in diminished CD8 T cell response in adulthood and impaired control of tumor growth and bacterial infection. We found that perinatal glucocorticoid exposure resulted in persistent alteration of the hypothalamic-pituitaryadrenal (HPA) axis. Consequently, the level of the hormone in adults was significantly reduced, resulting in decreased CD8 T cell function. Our study thus demonstrates that perinatal stress can have long-term consequences on CD8 T cell immunity by altering HPA axis activity.