Project description:The study was performed towards understanding transgenerational epigenetic inheritance at transcriptome level. The founder males of F0 generation (actin-GAL4/Pin; UASRNAi-mts/+), and the resulting, male-line derived F1 (Pin/+; +/+), and F2 (+/+; +/+) generation individuals were used as test lineage, and the wild-type w1118 progeny as control lineage flies. The fly strains used for generating founder F0 line included Pin/CyO-dYFP; UASRNAi-mts/MKRS, actin-GAL4/CyO; +/+, and w1118. Precursor strains, as appropriate, were outcrossed with w1118 to minimize genetic background differences.
Project description:Some epigenetic modifications are inherited from one generation to the next, providing a potential mechanism for the inheritance of environmentally acquired traits. Transgenerational inheritance of RNA interference phenotypes in C. elegans provides an excellent model to study this phenomenon, and whilst studies have implicated both chromatin modifications and small RNA pathways in heritable silencing their relative contributions remain unclear. Here we demonstrate that the histone methyltransferases SET-25 and SET-32 are required for the establishment of a transgenerational silencing signal, but not for long-term maintenance of this signal between subsequent generations suggesting that transgenerational epigenetic inheritance is a multi-step process, with distinct genetic requirements for establishment and maintenance of heritable silencing. Furthermore, small RNA sequencing reveals that the abundance of secondary siRNA (thought to be the effector molecules of heritable silencing) does not correlate with silencing phenotypes. Together, our results suggest that the current mechanistic models of epigenetic inheritance are incomplete.
Project description:The epigenetic transgenerational actions of environmental toxicants and relevant mixtures on ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1, F2 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling premature ovarian failure (POF). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states were induced by different classes of environmental compounds suggesting a role of environmental epigenetics in ovarian disease etiology. We used transcriptome microarray analysis to determine genes expressed differentially between F3 control and F3 vinclozolin lineage rat ovary granulosa cell and see which genes might be connected to or cause observed ovary diseases RNA samples from granulosa cell of 3 F3-control lineage groups are compared to granulosa cell of 3 F3-vinclozolin lineage groups
Project description:Environmentally induced epigenetic transgenerational inheritance of adult onset disease involves a variety of phenotypic changes suggesting a general alteration in genome activity. Investigation of eleven different tissue transcriptomes in male and female F3 generation vinclozolin versus control lineage rats demonstrated all tissues examined had unique transgenerational transcriptomes. Common cellular pathways and processes were identified among the tissues. A bionetwork analysis identified gene modules with coordinated gene expression and each had unique gene networks regulating tissue specific gene expression and function. A large number of statistically significant over-represented clusters of differentially expressed genes were identified and termed M-bM-^@M-^\Epigenetic Control RegionsM-bM-^@M-^]. Combined observations demonstrate that all tissues derived from the epigenetically altered germ line develop transgenerational transcriptomes unique to the tissue, but common epigenetic control regions in the genome appear to in part coordinately regulate these tissue specific transcriptomes. This systems biology approach provides insight into the molecular mechanisms involved in the epigenetic transgenerational inheritance of a variety of adult onset disease phenotypes. We used microarrays to determine genes expressed differentially in rats 11 male or female smatic tissues -male heart, kidney, liver, testis, prostate, seminal vesicles; female heart, kidney, liver, ovary, uterus - due to Vinclozolin treatments of their grand-grandmothers. For each of 11 male or female smatic tissues, RNA samples from 2 treatment groups - control (Con) and vinclozolin (Vin) - were compared to each other. Each treatment groups contained 3 biological replica. RNA for each replica was pooled from 2 individual animals.
Project description:Environmental compounds can promote epigenetic transgenerational inheritance of adult-onset disease in subsequent generations following ancestral exposure during fetal gonadal sex determination. The current study examined the ability of dioxin (2,3,7,8-tetrachlorodibenzo[p]dioxin, TCDD) to promote epigenetic transgenerational inheritance of disease and DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to dioxin during fetal day 8 to 14 and adult-onset disease was evaluated in F1 and F3 generation rats. The incidences of total disease and multiple disease increased in F1 and F3 generations. Prostate disease, ovarian primordial follicle loss and polycystic ovary disease were increased in F1 generation dioxin lineage. Kidney disease in males, pubertal abnormalities in females, ovarian primordial follicle loss and polycystic ovary disease were increased in F3 generation dioxin lineage animals. Analysis of the F3 generation sperm epigenome identified 50 differentially DNA methylated regions (DMR) in gene promoters. These DMR provide potential epigenetic biomarkers for transgenerational disease and ancestral environmental exposures. Observations demonstrate dioxin exposure of a gestating female promotes epigenetic transgenerational inheritance of adult onset disease and sperm epimutations. Methylated sperm DNA was isolated from rats ancestrally exposed to dioxin (Hip). Three independent samples from the treatment group were obtained. Differential DNA methylation between treatment groups was determined using Nimblegen microarrays. Treated samples were paired with control samples and hybridized together on arrays (Hip1/Cip1, Hip2/Cip2, and Hip3/Cip3), resulting in three arrays for the treatment.
Project description:The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling primary ovarian insufficiency (POI). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states was induced by all the different classes of environmental compounds, suggesting a role of environmental epigenetics in ovarian disease etiology. Granulosa cells from large antral follicles were collected and evaluated from F3 generation rats that were ancestrally exposed to one of the five different treatments: Vinclozolin, Pesticide (includes permethrin and DEET), Plastics (includes BPA, DBP and DEHP), Low-dose Plastics (50% of Plastics dose), Dioxin, Hydrocarbon (Jet fuel JP8), or DMSO vehicle as Control. Vinclozolin lineage alterations in differentially DNA methylated regions (DMR) in the granulosa cells was investigated by using a methylated DNA immunoprecipitation (MeDIP) procedure followed by comparative hybridization on a genome wide promoter tiling array (Chip), termed an MeDIP-Chip assay. The DNA fractions from four animals of the same treatment group were pooled to create three different pooled DNA samples from each of the two treatment groups (experimental vs. control). These DNA samples were then used for methylated DNA immunoprecipitation (MeDIP) using Nimblegen microarrays. Each MeDIP sample was then used to preform three different comparative (amplified MeDIP vs. amplified MeDIP) hybridization experiments (3 sub-arrays), each encompassing DNA samples from 24 animls (3 treatment and 3 control groups).
Project description:Environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of adult onset disease, including testis disease and male infertility. The exposure of a gestating female during the period of gonadal sex determination has been shown to promote sperm epimutations, differential DNA methylation regions (DMR), that transmit transgenerational disease to subsequent generations. The current study was designed to determine the impact of an altered sperm epigenome on the subsequent development of an adult somatic cell (Sertoli cell) that influences the onset of a specific disease (male infertility). A gestating female rat (F0 generation) was exposed to the agriculture fungicide vinclozolin during gonadal sex determination and then the subsequent F3 generation progeny used for the isolation of Sertoli cells and assessment of testis disease. As previously observed, a spermatogenic cell apoptosis was observed. The Sertoli cells that provide the physical and nutritional support for the spermatogenic cells were isolated and alterations in gene expression examined. Over 400 genes were differentially expressed in the F3 generation control versus vinclozolin lineage Sertoli cells. A number of specific signaling pathways and cellular processes were identified to be transgenerationally altered. One of the key metabolic processes affected was pyruvate/lactate production that is directly linked to spermatogenic cell viability. The Sertoli cell epigenome was also altered with over 100 promoter differential DNA methylation regions (DMR) modified in the vinclozolin F3 generation Sertoli cell. The genomic features and overlap with the sperm DMR were investigated. Observations demonstrate that the transgenerational sperm epigenetic alterations subsequently alters the development of a specific somatic cell (Sertoli cell) epigenome and transcriptome that then has a role in the adult onset disease (male infertility). The environmentally induced epigenetic transgenerational inheritance of testis disease appears to be a component of the molecular etiology of male infertility. Environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of adult onset male infertility. The exposure of a gestating female during the period of gonadal sex determination has been shown to promote sperm epimutations, differential DNA methylation regions (DMR), that transmit transgenerational disease to subsequent generations. The current study was designed to determine the impact of an altered sperm epigenome on the subsequent development of an adult somatic cell (Sertoli cell) that influences the onset of a specific disease (male infertility). A gestating female rat (F0 generation) was exposed to the agriculture fungicide vinclozolin during gonadal sex determination and then the subsequent F3 generation progeny used for the isolation of Sertoli cells and assessment of testis disease. The Sertoli cells provide the physical and nutritional support for the spermatogenic cells in the testis. The F3 generation Sertoli cells have an altered transcriptome and epigenome associated with adult onset testis disease. The environmentally induced epigenetic transgenerational inheritance of Sertoli cell abnormalities appears to be a component of the molecular etiology of male infertility. RNA samples from Sertoli cell of 3 F3-control lineage groups are compared to Sertoli cell of 3 F3-vinclozolin lineage groups
Project description:The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling primary ovarian insufficiency (POI). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states was induced by all the different classes of environmental compounds, suggesting a role of environmental epigenetics in ovarian disease etiology.
Project description:Transgenerational inheritance of acquired traits/characteristics from ancestors is believed to play important roles in evolution, as well as health problems/symptoms not due to “classical genetic inheritance”. However, the central enigma, such as how the acquired transgenerational characteristics are developed, and how the acquired traits are transmitted from generations to generations of offspring, largely remained veiled. In this study, we used C elegans as a model system and provide evidence that the dynamic of H3K27me3 as a hallmark and regulator for the gut-mediated transgenerational inheritance of acquired traits. Further, we demonstrate that yolk proteins guide the establishment of the acquired epigenetic imprints in soma, as well as determines the transgenerational inheritance of epigenetic imprints and subsequent acquired behavior in offspring by maternal provision. Taken together, our findings support that yolk proteins both function as a systemic “non-nuclear factor” for establishing the somatic epigenetic imprints and as a “cargo” to transmit acquired epigenetic information to the subsequent generations through oocytes.