Parental methylation patterns of a transgenic locus in adult somatic tissues are imprinted during gametogenesis

Development ◽  
1992 ◽  
Vol 116 (4) ◽  
pp. 831-839 ◽  
Author(s):  
T. Ueda ◽  
K. Yamazaki ◽  
R. Suzuki ◽  
H. Fujimoto ◽  
H. Sasaki ◽  
...  
Keyword(s):  
Germ Cells ◽  
Developmental Stages ◽  
Fusion Gene ◽  
Cpg Island ◽  
Methylation Status ◽  
Gene Promoter ◽  
Parental Origin ◽  
Chromosome 11 ◽  
Somatic Tissues ◽  
Methylation Patterns

The methylation status of a mouse metallothionein-I/human transthyretin fusion gene was studied during gametogenesis in transgenic mice. In the adult tissues of this mouse line, the promoter region of the transgene on chromosome 11 is methylated when it is maternally inherited and undermethylated when it is paternally inherited. Germ cells from various developmental stages of gametogenesis were isolated, and their DNAs were assayed using methylation-sensitive restriction endonucleases and the polymerase chain reaction. Only low to nonexistent levels of transgene methylation were detected in germ cells from 14.5-day-old male and female fetuses irrespective of the parental origin of the transgene. This undermethylated state persisted in oocytes from newborn females as well as in testicular spermatogenic cells and sperm. By contrast, the transgene promoter was completely methylated in fully grown oocytes arrested at the first meiotic prophase. The endogenous metallothionein-I gene promoter, located on a different chromosome, remained undermethylated at all stages examined, consistent with previous findings reported for a typical CpG island. Taken together, the results suggest that parental-specific adult patterns of transgene methylation are established during gametogenesis.

Pyrosequencing Analysis of the Methylation Status of the CpG Island in the Retinoic Acid Receptor-β2 (RAR-β2) Gene Promoter.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4297-4297
Author(s):  
Da-Cheng Zhou ◽  
David Reynolds ◽  
Robert E. Gallagher
Keyword(s):  
Retinoic Acid ◽  
Cell Lines ◽  
Cpg Island ◽  
Retinoic Acid Receptor ◽  
Methylation Status ◽  
Cpg Islands ◽  
Leukemia Cell ◽  
Gene Promoter ◽  
Cpg Dinucleotides ◽  
Retinoic Acid Receptor Β2

Abstract CpG islands are associated with the 5′-ends of most housekeeping genes and many regulated genes. We have hypothesized that the methylation status of CpG islands in the promoter region of all-trans retinoic acid (ATRA) target genes such as retinoic acid receptor-β2 (RAR-β2) may be related to ATRA resistance and relapse of acute promyelocytic leukemia (APL). In the present study, we developed a highly quantitative method to assess the degree of DNA methylation at specific sites using PyrosequencingTM technology (Biotage, Uppsala, Sweden). This method is more quantitative than methylation-specific PCR, and is as accurate as but simpler and more robust than combined bisulfite restriction analysis (COBRA) or direct sequencing of plasmid clones of PCR products. We used this method to study 14 CpG dinucleotides in the CpG island of the RAR-β2 promoter. In reconstruction experiments in which 100% methylated and 100% unmethylated DNAs were admixed in different proportions (100:0; 80:20, 60:40, etc), a straightline graph was obtained over the entire range from 0 – 100% for each of the 14 CpG dinucleotides (r2 > 0.98). The results were highly reproducible and the variation between the results obtained from repetitive pyrosequencing of the same DNA was very low (S.D.<2%). Also the standard deviation between measurements of different PCR-amplified, bisulfite-converted DNAs prepared in separate experiments was <5%. We then used this method to measure the methylation level of the CpG island of the RAR-β2 promoter in several leukemia cell lines. Of 3 APL cell lines, the two with PML-RARα mutations, i.e., UF-1 and AP-1060, had higher overall methylation, compared to the NB4 cell line with non-mutant PML-RARα (mean ± SD = 52 ± 25% and 55 ± 21%, versus 43 ± 20%; p = 0.04 and 0.08, respectively; SD calculated from the variation across the 14 CpG dinucleotides for each source). Two myeloid leukemia cell lines with predominantly erythroid lineage characteristics, K562 and TF-1, had much lower levels of RAR-β2 methylation (2.6 ± 0.9% and 8.9 ± 3.2%, respectively). In the AP-1060 culture system, recently developed in our lab, there was little difference in methylation status between the patient bone marrow source and an intermediate, non-immortalized cell strain AP-1060S (27 ± 13% vs. 31 ± 25%). Further, there was no difference between lower and higher passage generations of AP-1060S (31 ± 25% vs. 30 ± 26%), which had markedly different replicative potential, indicating that replicative senescence at higher AP-1060 passages was not associated with altered methylation of the RAR-β2 gene promoter. However, the established, immortalized AP-1060 cell line had significantly greater methylation (52 ± 25%) than either the bone marrow source or AP-1060S (p <0.0001 and p = 0.0002, respectively), consistent with published reports of increased promoter methylation of cell lines. In conclusion, pyrosequencing is a high throughput method with great quantitative strength, and can be used for accurate and consistent analysis of methylation status in large numbers of samples.

scholarly journals Identification and characterization of a cDNA and the gene encoding the mouse ubiquitously expressed glucose-6-phosphatase catalytic subunit-related protein

2004 ◽  
Vol 32 (1) ◽  
pp. 33-53 ◽  
Author(s):  
JN Boustead ◽  
CC Martin ◽  
JK Oeser ◽  
CA Svitek ◽  
SI Hunter ◽  
...  
Keyword(s):  
Fusion Gene ◽  
Gene Promoter ◽  
Catalytic Subunit ◽  
Mouse Tissue ◽  
Related Protein ◽  
Subunit Gene ◽  
Chromosome 11 ◽  
Gene Encoding ◽  
Identification And Characterization

Glucose-6-phosphatase (G6Pase) catalyzes the final step in the gluconeogenic and glycogenolytic pathways, the hydrolysis of glucose-6-phosphate (G6P) to glucose and phosphate. This paper describes the identification and characterization of a cDNA and the gene encoding the mouse ubiquitously expressed G6Pase catalytic subunit-related protein (UGRP). The open reading frame of this UGRP cDNA encodes a protein (346 amino acids (aa); Mr 38,755) that shares 36% overall identity (56% similarity) with the mouse G6Pase catalytic subunit (357 aa; Mr 40,454). UGRP exhibits a similar predicted transmembrane topology and conservation of many of the catalytically important residues with the G6Pase catalytic subunit; however, unlike the G6Pase catalytic subunit, UGRP does not catalyze G6P hydrolysis and does not contain a carboxy-terminal di-lysine endoplasmic reticulum retention signal. UGRP mRNA was detected by RNA blot analysis in every mouse tissue examined with the highest expression in heart, brain, testis and kidney. Database analysis showed that the mouse UGRP gene is composed of six exons, spans approximately 4.2 kbp of genomic DNA and is located on chromosome 11 along with the G6Pase catalytic subunit gene. The UGRP gene transcription start sites were mapped by primer extension analysis, and the activity of the mouse UGRP gene promoter was analyzed using luciferase fusion gene constructs. In contrast to the G6Pase catalytic subunit gene promoter, the UGRP promoter was highly active in all cell lines examined.

scholarly journals Quantitative High-Resolution CpG Island Mapping with Pyrosequencing™ Reveals Disease-Specific Methylation Patterns of the CDKN2B Gene in Myelodysplastic Syndrome and Myeloid Leukemia

2007 ◽  
Vol 53 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Kai Brakensiek ◽  
Luzie U Wingen ◽  
Florian Länger ◽  
Hans Kreipe ◽  
Ulrich Lehmann
Keyword(s):  
Myelodysplastic Syndrome ◽  
Myeloid Leukemia ◽  
Cpg Island ◽  
Methylation Status ◽  
Low Grade ◽  
Myeloid Malignancies ◽  
Cpg Sites ◽  
Methylation Patterns ◽  
Cdkn2b Gene ◽  
Disease Specific

Abstract Background: Gene silencing through aberrant CpG island methylation is the most extensively analyzed epigenetic event in human tumorigenesis and has huge diagnostic and prognostic potential. Methylation patterns are often very heterogeneous, however, presenting a serious challenge for the development of methylation assays for diagnostic purposes. Methods: We used Pyrosequencing™ technology to determine the methylation status of 68 CpG sites in the CpG island of the CDKN2B gene [cyclin-dependent kinase inhibitor 2B (p15, inhibits CDK4)], frequently hypermethylated in myeloid malignancies, in a series of bone marrow samples from patients with myelodysplasia and myeloid leukemia (n = 82) and from 32 controls. A total of 7762 individual methylation sites were quantitatively evaluated. Precision and reproducibility of the quantification was evaluated with several overlapping primers. Results: The use of optimized sequencing primers and the new Pyro Q-CpG™ software enabled precise and reproducible quantification with a single sequencing primer of up to 15 CpG sites distributed over ∼100 bp. Extensive statistical analyses of the whole CpG island revealed for the first time disease-specific methylation patterns of the CDKN2B gene in myeloid malignancies and small regions of differential methylation with high discriminatory power that enabled differentiation of even low-grade myelodysplastic syndrome samples from the controls, a result that was confirmed in an independent group of 9 control and 36 patient samples. Conclusion: The precise quantitative methylation mapping of whole CpG islands is now possible with Pyrosequencing software in combination with optimized sequencing primers. This method reveals disease-specific methylation patterns and enables the development of specific diagnostic assays.

The Relation of the Interrenal Blastema to the Origin of the Somatic Tissues of the Gonad in Frog Tadpoles

Development ◽  
1954 ◽  
Vol 2 (4) ◽  
pp. 275-289
Author(s):  
Enrico Vannini ◽  
Armando Sabbadin
Keyword(s):  
Germ Cells ◽  
Developmental Stages ◽  
Primordial Germ Cells ◽  
Lateral Position ◽  
Medullary Tissue ◽  
Somatic Tissues ◽  
Frog Tadpoles ◽  
Dorsal Mesentery

As long ago as 1941 and 1942 one of us (Vannini) found in a series of developmental stages of frog tadpoles that the somatic components of the medullary tissue of the gonad have their origin in the interrenal blastema, and not, as was then generally supposed, in the mesonephric blastema. In the earliest stages examined at that time the gonad rudiment had the structure of ‘paired genital ridges’, lying at each side of the dorsal mesentery, and were furnished with primordial germ-cells, but were still without medullary tissue. The interrenal blastema occupied a median site in the tadpole's body, ventral to the aorta and dorsal to the two subcardinal veins. The mesonephric blastemata appeared distinctly separate from the interrenal rudiment, because they were situated in a more lateral position, contiguous with the Wolffian ducts. In later stages the medullary tissue (‘medulla’) penetrated within the genital ridges.

scholarly journals Regulation of the Human Secretin Gene Is Controlled by the Combined Effects of CpG Methylation, Sp1/Sp3 Ratio, and the E-Box Element

2004 ◽  
Vol 18 (7) ◽  
pp. 1740-1755 ◽  
Author(s):  
Leo Tsz-On Lee ◽  
Kian-Cheng Tan-Un ◽  
Ronald Ting-Kai Pang ◽  
David Tai-Wai Lam ◽  
Billy Kwok-Chong Chow
Keyword(s):  
Gene Expression ◽  
Hepg2 Cells ◽  
Cpg Island ◽  
Methylation Status ◽  
Gene Promoter ◽  
Mobility Shift ◽  
Specific Pcr ◽  
E Box

Abstract To unravel the mechanisms that regulate the human secretin gene expression, in this study, we have used secretin-expressing (HuTu-80 cells, human duodenal adenocarcinoma) and non-secretin-expressing [PANC-1 (human pancreatic ductile carcinoma) and HepG2 (human hepatocellular carcinoma) cells] cell models for in vitro and in vivo analyses. By transient transfection assays, within the promoter region (−11 to −341 from ATG, relative to the ATG initiation codon), we have initially identified several functional motifs including an E-box and 2 GC-boxes. Results from gel mobility shift and chromatin immunoprecipitation assays confirmed further that NeuroD, E2A, Sp1, and Sp3 bind to these E- and GC-boxes in HuTu-80 cells in vitro and in vivo, whereas only high levels of Sp3 is observed to bind the promoter in HepG2 cells. In addition, overexpression of Sp3 resulted in a dose-dependent repression of the Sp1-mediated transactivation. Collectively, these data suggest that the Sp1/Sp3 ratio is instrumental to controlling secretin gene expression in secretin-producing and non-secretin-producing cells. The functions of GC-box and Sp proteins prompted us to investigate the possible involvement of DNA methylation in regulating this gene. Consistent with this idea, we found a putative CpG island (−336 to 262 from ATG) that overlaps with the human secretin gene promoter. By methylation-specific PCR, all the CpG dinucleo-tides (26 of them) within the CpG island in HuTu-80 cells are unmethylated, whereas all these sites are methylated in PANC-1 and HepG2 cells. The expressions of secretin in PANC-1 and HepG2 cells were subsequently found to be significantly activated by a demethylation agent, 5′-Aza-2′ deoxycytidine. Taken together, our data indicate that the human secretin gene is controlled by the in vivo Sp1/Sp3 ratio and the methylation status of the promoter.

scholarly journals Gene Promoter Methylation Patterns throughout the Process of Cervical Carcinogenesis

2010 ◽  
Vol 32 (1-2) ◽  
pp. 131-143
Author(s):  
Nan Yang ◽  
Esther R. Nijhuis ◽  
Haukeline H. Volders ◽  
Jasper J. H. Eijsink ◽  
Ágnes Lendvai ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Methylation Status ◽  
Gene Promoter ◽  
Low Grade ◽  
Depth Of Invasion ◽  
Cervical Carcinogenesis ◽  
Normal Epithelium ◽  
Methylation Frequency ◽  
Cervical Cancers ◽  
Methylation Patterns

Objectives: To determine methylation status of nine genes, previously described to be frequently methylated in cervical cancer, in squamous intraepithelial lesions (SIL).Methods: QMSP was performed in normal cervix, low-grade (L)SIL, high-grade (H)SIL, adenocarcinomas and squamous cell cervical cancers, and in corresponding cervical scrapings.Results: Only CCNA1 was never methylated in normal cervices and rarely in LSILs. All other genes showed methylation in normal cervices, with CALCA, SPARC and RAR-β2 at high levels. Methylation frequency of 6 genes (DAPK, APC, TFPI2, SPARC, CCNA1 and CADM1) increased with severity of the underlying cervical lesion. DAPK showed the highest increase in methylation frequency between LSIL and HSIL (10% vs. 40%, p < 0.05), while CCNA1 and TFPI2 were most prominently methylated in cervical cancers compared to HSILs (25% vs. 52%, p < 0.05, 30% vs. 58%, p < 0.05). CADM1 methylation in cervical cancers was related to depth of invasion (p < 0.05) and lymph vascular space involvement (p < 0.01), suggesting a role in invasive potential of cervical cancers. Methylation ratios in scrapings reflected methylation status of the underlying lesions (p < 0.05).Conclusion: Methylation of previously reported cervical cancer specific genes frequently occurs in normal epithelium. However, frequency of methylation increases during cervical carcinogenesis, with CCNA1 and DAPK as the best markers to distinguish normal/LSIL from HSIL/cancer lesions.

scholarly journals A DNA signal from the Thy-1 gene defines de novo methylation patterns in embryonic stem cells.

1990 ◽  
Vol 10 (8) ◽  
pp. 4396-4400 ◽  
Author(s):  
M Szyf ◽  
G Tanigawa ◽  
P L McCarthy
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Dna Sequences ◽  
De Novo ◽  
Cpg Island ◽  
Embryonic Stem ◽  
Cpg Dinucleotides ◽  
Somatic Tissues ◽  
Methylation Patterns ◽  
De Novo Methylation

Although DNA can be extensively methylated de novo when introduced into pluripotent cells, the CpG island in the Thy-1 gene does not become methylated either in the mouse embryo or in embryonic stem cells. A 214-base-pair region near the promoter of the Thy-1 gene protects itself as well as heterologous DNA sequences from de novo methylation. We propose that this nucleotide sequence is representative of a class of important signals that limits de novo methylation in the embryo and establishes the pattern of hypomethylated CpG dinucleotides found in somatic tissues.

scholarly journals Expression of Sclerostin in Osteoporotic Fracture Patients Is Associated with DNA Methylation in the CpG Island of the SOST Gene

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Yanming Cao ◽  
Bin Wang ◽  
Ding Wang ◽  
Dongxiang Zhan ◽  
Caiyuan Mai ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Osteoporotic Fracture ◽  
Cpg Island ◽  
Epigenetic Modification ◽  
Methylation Status ◽  
Gene Promoter ◽  
Primary Osteoporosis ◽  
Sost Gene ◽  
Fracture Bone

Purpose. SOST gene is one of the key factors in regulating bone absorption. Although there are reports showing diverse transcription factors, epigenetic modification could be responsible for regulating SOST gene expression. There is still little exploration on promoter methylation status of SOST gene in osteoporotic bone tissues. The aim of this study is to investigate the involvement of CpG methylation in regulation of SOST expression in patients with primary osteoporosis. Methods. The diagnosis of osteoporosis was established on the basis of dual energy X-ray absorptiometry to measure BMD. All femoral bone tissues were separated in surgeries. After extracting total RNA and protein, we checked the relative expression levels of SOST by quantitative real-time PCR and western blot. Also, immunohistochemical staining was performed to observe the expression of SOST protein in the bone samples. The genomic DNA of non-OPF (non-osteoporotic fracture bone tissues) and OPF (osteoporotic fracture bone tissues) were treated by bisulfite modification, and methylation status of CpG sites in the CpG island of SOST gene promoter was determined by DNA sequencing. Results. SOST gene expression in the non-OPF group was lower than that in OPF group. Bisulfite sequencing result showed that SOST gene promoter was slightly demethylated in the OPF group, as compared with non-OPF group. Conclusion. Our study demonstrated that DNA methylation influenced the transcriptional expression of SOST gene, which probably may play an important role in the pathogenesis of primary osteoporosis.

scholarly journals A Long Polymorphic GT Microsatellite within a Gene Promoter Mediates Non-Imprinted Allele-Specific DNA Methylation of a CpG Island in a Goldfish Inter-Strain Hybrid

2019 ◽  
Vol 20 (16) ◽  
pp. 3923
Author(s):  
Zheng ◽  
Xu ◽  
Cao
Keyword(s):  
Dna Methylation ◽  
Cpg Island ◽  
Methylation Status ◽  
Repetitive Sequences ◽  
Gene Promoter ◽  
Dna Polymorphisms ◽  
Specific Expression ◽  
Cis Acting ◽  
Allele Specific ◽  
The Impact

It is now widely accepted that allele-specific DNA methylation (ASM) commonly occurs at non-imprinted loci. Most of the non-imprinted ASM regions observed both within and outside of the CpG island show a strong correlation with DNA polymorphisms. However, what polymorphic cis-acting elements mediate non-imprinted ASM of the CpG island remains unclear. In this study, we investigated the impact of polymorphic GT microsatellites within the gene promoter on non-imprinted ASM of the local CpG island in goldfish. We generated various goldfish heterozygotes, in which the length of GT microsatellites or some non-repetitive sequences in the promoter of no tail alleles was different. By examining the methylation status of the downstream CpG island in these heterozygotes, we found that polymorphisms of a long GT microsatellite can lead to the ASM of the downstream CpG island during oogenesis and embryogenesis, polymorphisms of short GT microsatellites and non-repetitive sequences in the promoter exhibited no significant effect on the methylation of the CpG island. We also observed that the ASM of the CpG island was associated with allele-specific expression in heterozygous embryos. These results suggest that a long polymorphic GT microsatellite within a gene promoter mediates non-imprinted ASM of the local CpG island in a goldfish inter-strain hybrid.

Sign in / Sign up

Export Citation Format

Share Document