Dataset Information

Cloning and Characterization of 3.1kb Promoter Region of the Oct4 Gene from the Fischer 344 Rat.

ABSTRACT: Here, the role of methylation in regulation of rat Oct4 gene was evaluated during embryonic development, in adult tissues and in embryo-derived cells. First, the region 3.1 kb upstream to the rat Oct4 ATG site was cloned and sequenced. The rat Oct4 upstream sequence was similar to that in bovine, mouse and human with two upstream elements: proximal (PE) and distal enhancers (DE) and four homology conserved regions (CR1-4). The conserved regions in the rat have 69% - 96% homology with bovine, human, mouse sequences. Next, the methylation pattern in the promoter was determined during embryonic development, in adult tissues, in rat embryonic stem cell (ESC)-like cells and umbilical cord-derived cells (the feeder for ESC-like cells) using the bisulfite method and DNA sequencing. The promoter was methylated in adult and fetal tissues, and in days post coitus (DPC) 10.5 and 12.5 embryos and hypomethylated in DPC4.5 embryos and in rat ESC-like cells. The expression of Oct4 was evaluated by qRT-PCR. DPC4.5 embryos and rat ESC-like cells had higher expression of the Oct4 gene compared to DPC10.5 and 12.5 embryos, adult tissues and embryoid bodies derived from rat ESC-like cells. Thus, the methylation status correlated with the qRT-PCR results. These results indicate that the rat Oct4 3.1kb promoter region is organized and contains transcription binding and regulatory sites similar to those described for bovine, mouse and human. The rat Oct4 promoter is methylated during embryonic development after 4.5 DPC and during differentiation of rat ESC-like cells to embryoid bodies.

SUBMITTER: He H

PROVIDER: S-EPMC3280817 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Cloning and Characterization of 3.1kb Promoter Region of the Oct4 Gene from the Fischer 344 Rat.

He Hong H McHaney Mark M Hong James J Weiss Mark L ML

The open stem cell journal 20090101 1

Here, the role of methylation in regulation of rat Oct4 gene was evaluated during embryonic development, in adult tissues and in embryo-derived cells. First, the region 3.1 kb upstream to the rat Oct4 ATG site was cloned and sequenced. The rat Oct4 upstream sequence was similar to that in bovine, mouse and human with two upstream elements: proximal (PE) and distal enhancers (DE) and four homology conserved regions (CR1-4). The conserved regions in the rat have 69% - 96% homology with bovine, hum ...[more]

PMID: 22347989

Similar Datasets

Project description:Current human reproductive risk assessment methods rely on semen and serum hormone analyses, which are not easily comparable to the histopathological endpoints and mating studies used in animal testing. Because of these limitations, there is a need to develop universal evaluations that reliably reflect male reproductive function. We hypothesized that toxicant-induced testicular injury can be detected in sperm using mRNA transcripts as indicators of insult. To test this, we exposed adult male Fischer 344 rats to low doses of model testicular toxicants and classically characterized the testicular injury while simultaneously evaluating sperm mRNA transcripts from the same animals. Overall, this study aimed to: 1) identify sperm transcripts altered after exposure to the model testicular toxicant, 2,5-hexanedione (HD) using microarrays; 2) expand on the HD-induced transcript changes in a comprehensive time course experiment using qRT-PCR arrays; and 3) test these injury indicators after exposure to another model testicular toxicant, carbendazim (CBZ). Microarray analysis of HD-treated adult Fischer 344 rats identified 128 altered sperm mRNA transcripts when compared to control using linear models of microarray analysis (q<0.05). All transcript alterations disappeared after 3 months of post-exposure recovery. In the time course experiment, time-dependent alterations were observed for 12 candidate transcripts selected from the microarray data based upon fold change and biological relevance, and 8 of these transcripts remained significantly altered after the 3-month recovery period (p<0.05). In the last experiment, 8 candidate transcripts changed after exposure to CBZ (p<0.05). The two testicular toxicants produced distinct molecular signatures with only 4 overlapping transcripts between them, each occurring in opposite directions. Overall, these results suggest that sperm mRNA transcripts are indicators of low dose toxicant-induced testicular injury in the rat.

Project description:BackgroundBisphenol A (BPA) is an endocrine-disrupting chemical that may contribute to development of obesity and metabolic disorders. Humans are constantly exposed to low concentrations of BPA, and studies support that the developmental period is particularly sensitive.ObjectivesThe aim was to investigate the effects of low-dose developmental BPA exposure on metabolic parameters in male and female Fischer 344 (F344) rat offspring.MethodsPregnant F344 rats were exposed to BPA via their drinking water, corresponding to 0.5 ?g/kg BW/d (BPA0.5; n=21) or 50 ?g/kg?BW/d (BPA50; n=16), from gestational day (GD) 3.5 until postnatal day (PND) 22, and controls were given vehicle (n=26). Body weight (BW), adipose tissue, liver (weight, histology, and gene expression), heart weight, and lipid profile were investigated in the 5-wk-old offspring.ResultsMales and females exhibited differential susceptibility to the different doses of BPA. Developmental BPA exposure increased plasma triglyceride levels (0.81±0.10 mmol/L compared with 0.57±0.03 mmol/L, females BPA50 p=0.04; 0.81±0.05 mmol/L compared with 0.61±0.04 mmol/L, males BPA0.5 p=0.005) in F344 rat offspring compared with controls. BPA exposure also increased adipocyte cell density by 122% in inguinal white adipose tissue (iWAT) of female offspring exposed to BPA0.5 compared with controls (68.2±4.4 number of adipocytes/HPF compared with 55.9±1.5 number of adipocytes/HPF; p=0.03) and by 123% in BPA0.5 females compared with BPA50 animals (68.2±4.4 number of adipocytes/high power field (HPF) compared with 55.3±2.9 number of adipocytes/HPF; p=0.04). In iWAT of male offspring, adipocyte cell density was increased by 129% in BPA50-exposed animals compared with BPA0.5-exposed animals (69.9±5.1 number of adipocytes/HPF compared with 54.0±3.4 number of adipocytes/HPF; p=0.03). Furthermore, the expression of genes involved in lipid and adipocyte homeostasis was significantly different between exposed animals and controls depending on the tissue, dose, and sex.ConclusionsDevelopmental exposure to 0.5 ?g/kg?BW/d of BPA, which is 8-10 times lower than the current preliminary EFSA (European Food Safety Authority) tolerable daily intake (TDI) of 4 ?g/kg?BW/d and is within the range of environmentally relevant levels, was associated with sex-specific differences in the expression of genes in adipose tissue plasma triglyceride levels in males and adipocyte cell density in females when F344 rat offspring of dams exposed to BPA at 0.5 ?g/kg?BW/d were compared with the offspring of unexposed controls. https://doi.org/10.1289/EHP505.

Project description:To provide insights into the mode of action for Ni3S2 lung carcinogenicity by examining gene expression changes in target cells after inhalation exposure. Gene expression changes were determined in micro-dissected lung broncho-alveolar cells from Fischer F344 rats following inhalation of Ni3S2 at 0.0, 0.04, 0.08, 0.15, and 0.60 mg/m3 (0.03, 0.06, 0.11, and 0.44 mg Ni/m3) for one and four weeks (6 hours per day, 5 days per week). Results: Broncho-alveolar lavage fluid evaluation and lung histopathology provided evidence of inflammation only at the two highest concentrations, which were similar to those tested in the 2-year bioassay. The number of statistically significant up- and down-regulated genes decreased markedly from one to four weeks of exposure, suggesting adaptation. Cell signal pathway enrichment at both time-points primarily reflected responses to toxicity, including inflammatory and proliferative signaling. While proliferative signaling was up-regulated at both time points, some inflammatory signaling reversed from down-regulation at 1 week to up-regulation at 4 weeks. Conclusions: These results support a mode of action for Ni3S2 carcinogenicity driven by chronic toxicity, inflammation and proliferation, leading to mis-replication, rather than by direct genotoxicity. Benchmark dose (BMD) analysis identified the lowest pathway transcriptional BMD exposure concentration as 0.026 mg Ni/m3, for apoptosis/survival signaling. When conducted on the basis of lung Ni concentration the lowest pathway BMD was 0.64 M-BM-5g Ni/g lung, for immune/inflammatory signaling. Implications: These highly conservative BMDs could be used to derive a point of departure in a nonlinear risk assessment for Ni3S2 toxicity and carcinogenicity. Gene expression changes were determined in micro-dissected lung broncho-alveolar cells from Fischer F344 rats following inhalation of Ni3S2 at 0.0, 0.04, 0.08, 0.15, and 0.60 mg/m3 (0.03, 0.06, 0.11, and 0.44 mg Ni/m3) for one and four weeks (6 hours per day, 5 days per week).

Dataset Information

Cloning and Characterization of 3.1kb Promoter Region of the Oct4 Gene from the Fischer 344 Rat.

Publications

Cloning and Characterization of 3.1kb Promoter Region of the Oct4 Gene from the Fischer 344 Rat.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets