In this investigation we analysed the maintenance methylation activity of the mammalian cell DNA methyltransferase by microinjection of hemimethylated HSV-tk DNA into thymidine kinase-negative rat 2 cells. We found that the hemimethylated DNA was efficiently converted into symmetrical methylated molecules before DNA replication. Furthermore, integration of the trans-DNA into the host genome is an early event after gene transfer.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0014-5793(91)80599-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In order to determine whether partial methylation of the herpes simplex virus (HSV) tk gene prevents tk gene expression, the HSV tk gene was cloned as single-stranded DNA. By in vitro second-strand DNA synthesis, specific HSV tk gene segments were methylated, and the hemimethylated DNA molecules were microinjected into thymidine kinase-negative rat2 cells. Conversion of the hemimethylated DNA into symmetrical methylated DNA and integration into the host genome occurred early after gene transfer, before the cells entered into the S phase.
View Article and Find Full Text PDFAfter microinjection hemimethylated DNA is converted into symmetrically methylated DNA before DNA replication.
FEBS Lett
June 1991
Institut für Molekularbiologie und Biochemie, Freien Universitt Berlin, Germany.
In this investigation we analysed the maintenance methylation activity of the mammalian cell DNA methyltransferase by microinjection of hemimethylated HSV-tk DNA into thymidine kinase-negative rat 2 cells. We found that the hemimethylated DNA was efficiently converted into symmetrical methylated molecules before DNA replication. Furthermore, integration of the trans-DNA into the host genome is an early event after gene transfer.
View Article and Find Full Text PDFRapid and apparently error-prone excision repair of nonreplicating UV-irradiated plasmids in Xenopus laevis oocytes.
Mol Cell Biol
July 1990
Department of Agricultural Chemistry, Oregon State University, Corvallis 97331-6502.
Repair of UV-irradiated plasmid DNA microinjected into frog oocytes was measured by two techniques: transformation of repair-deficient (delta uvrB delta recA delta phr) bacteria, and removal of UV endonuclease-sensitive sites (ESS). Transformation efficiencies relative to unirradiated plasmids were used to estimate the number of lethal lesions; the latter were assumed to be Poisson distributed. These estimates were in good agreement with measurements of ESS.
View Article and Find Full Text PDFHemimethylation of DNA prevents chromatin expression.
Proc Natl Acad Sci U S A
March 1990
Institut fuer Molekularbiologie und Biochemie der Freien, Universitaet Berlin, Federal Republic of Germany.
The activity of hemimethylated herpes simplex virus thymidine kinase DNA and chromatin was analyzed by microinjection and thymidine incorporation into the DNA of thymidine kinase-negative Rat2 cells. Hemimethylated DNA was obtained by in vitro replication of single-stranded M13 DNA constructs and of chromatin produced by in vitro reconstitution of the DNA with purified chicken histone octamers. We found that methylation of either the coding or the noncoding DNA strand was sufficient to block expression of the hemimethylated chromatin.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!