Sperm Performance Better on Diamond than on Polystyrene

In contrast to many other genes containing a CpG island, the testis-specific H2B (TH2B) histone gene exhibits tissue-specific methylation patterns in correlation with gene activity. Characterization of the methylation patterns within a 20-kb segment containing the TH2A and TH2B genes in comparison with that in a somatic histone cluster revealed that: (i) the germ cell-specific unmethylated domain of the TH2A and TH2B genes is defined as a small region surrounding the CpG islands of the TH2A and TH2B genes and (ii) somatic histone genes are unmethylated in both liver and germ cells, like other genes containing CpG islands, whereas flanking sequences are methylated. Transfection of in vitro-methylated TH2B, somatic H2B, and mouse metallothionein I constructs into F9 embryonal carcinoma cells revealed that the CpG islands of the TH2A and TH2B genes were demethylated like those of the somatic H2A and H2B genes and the metallothionein I gene. The demethylation of those CpG islands became significantly inefficient at a high number of integrated copies and a high density of methylated CpG dinucleotides. In contrast, three sites in the somatic histone cluster, of which two sites are located in the long terminal repeat of an endogenous retrovirus-like sequence, were efficiently demethylated even at a high copy number and a high density of methylated CpG dinucleotides. These results suggest two possible mechanisms for demethylation in F9 cells and methylation of CpG islands of the TH2A and TH2B genes at the postblastula stage during embryogenesis.

Download Full-text

Demethylation of somatic and testis-specific histone H2A and H2B genes in F9 embryonal carcinoma cells.

Molecular and Cellular Biology ◽

10.1128/mcb.13.9.5538 ◽

1993 ◽

Vol 13 (9) ◽

pp. 5538-5548 ◽

Cited By ~ 24

Author(s):

Y C Choi ◽

C B Chae

Keyword(s):

Embryonal Carcinoma ◽

Cpg Island ◽

Cpg Islands ◽

High Density ◽

Carcinoma Cells ◽

Embryonal Carcinoma Cells ◽

Cpg Dinucleotides ◽

F9 Embryonal Carcinoma Cells ◽

Methylation Patterns

In contrast to many other genes containing a CpG island, the testis-specific H2B (TH2B) histone gene exhibits tissue-specific methylation patterns in correlation with gene activity. Characterization of the methylation patterns within a 20-kb segment containing the TH2A and TH2B genes in comparison with that in a somatic histone cluster revealed that: (i) the germ cell-specific unmethylated domain of the TH2A and TH2B genes is defined as a small region surrounding the CpG islands of the TH2A and TH2B genes and (ii) somatic histone genes are unmethylated in both liver and germ cells, like other genes containing CpG islands, whereas flanking sequences are methylated. Transfection of in vitro-methylated TH2B, somatic H2B, and mouse metallothionein I constructs into F9 embryonal carcinoma cells revealed that the CpG islands of the TH2A and TH2B genes were demethylated like those of the somatic H2A and H2B genes and the metallothionein I gene. The demethylation of those CpG islands became significantly inefficient at a high number of integrated copies and a high density of methylated CpG dinucleotides. In contrast, three sites in the somatic histone cluster, of which two sites are located in the long terminal repeat of an endogenous retrovirus-like sequence, were efficiently demethylated even at a high copy number and a high density of methylated CpG dinucleotides. These results suggest two possible mechanisms for demethylation in F9 cells and methylation of CpG islands of the TH2A and TH2B genes at the postblastula stage during embryogenesis.

Download Full-text

Ectopic activation of WNT signaling in human embryonal carcinoma cells and its effects in short- and long-term in vitro culture

Scientific Reports ◽

10.1038/s41598-019-48396-7 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Yaser Atlasi ◽

Rebecca T. van Dorsten ◽

Andrea Sacchetti ◽

Rosalie Joosten ◽

J. Wolter Oosterhuis ◽

...

Keyword(s):

Wnt Signaling ◽

In Vitro Culture ◽

Embryonal Carcinoma ◽

Carcinoma Cells ◽

Embryonal Carcinoma Cells ◽

Ectopic Activation ◽

Short And Long Term

Download Full-text

Multiple CArG boxes in the human cardiac actin gene promoter required for expression in embryonic cardiac muscle cells developing in vitro from embryonal carcinoma cells.

Molecular and Cellular Biology ◽

10.1128/mcb.11.9.4796 ◽

1991 ◽

Vol 11 (9) ◽

pp. 4796-4803 ◽

Cited By ~ 59

Author(s):

G Pari ◽

K Jardine ◽

M W McBurney

Keyword(s):

Cardiac Muscle ◽

Embryonal Carcinoma ◽

Core Promoter ◽

Carcinoma Cells ◽

Regulatory Sequences ◽

Embryonal Carcinoma Cells ◽

Cardiac Muscle Cells ◽

Cardiac Actin ◽

Actin Promoter

Chimeric genes composed of the human cardiac actin promoter driving the Escherichia coli lacZ reporter gene were constructed, transfected, and stably integrated into genomes of P19 embryonal carcinoma cells. The transfected constructs were expressed actively in cardiac myocytes formed following dimethyl sulfoxide (DMSO)-induced cell differentiation but poorly in undifferentiated cultures and in cultures treated with retinoic acid to develop into derivatives of the neuroectoderm. A number of deletions of the promoter were constructed and tested. Three regions required for efficient expression in P19-derived cardiac muscle were identified, each containing sequences referred to as CArG boxes (CC[AT-rich]6GG). This analysis indicated that regulatory sequences important for expression in cardiac muscle were present upstream of the core promoter identified previously by transient assays in skeletal myoblasts. Expression of the cardiac actin promoter was enhanced 10-fold in undifferentiated P19 cells in the presence of the myoD protein. The promoter regions important for expression in P19-derived cardiocytes were similar to those important for myoD-induced enhancement, a result we interpret to be consistent with the idea that cardiac muscle might contain a myoD-like activity.

Download Full-text