5-Bromodeoxyuridine suppresses position effect variegation of transgenes in HeLa cells.
An ectopic gene integrated in the host genome is occasionally silenced due to a position effect of its adjacent chromatin structure. We found that 5-bromodeoxyuridine clearly activated such a transgene in HeLa cells. The transgene was also activated to various degrees by inhibitors of histone deacetylase, DNA topoisomerases, or DNA methyltransferase. The peptide antibiotic distamycin A potentiated markedly the effect of 5-bromodeoxyuridine. Transient expression of an artificial AT-hook protein termed MATH20 also potentiated its effect although significantly activated the transgene alone. Since distamycin A and MATH20 are able to displace histone H1 and other DNA-binding proteins bound to specific AT-rich sequences by a dominant, mutually exclusive fashion, these results suggest that 5-bromodeoxyuridine targets such an AT-rich sequence located adjacent to the silenced transgene, resulting in chromatin accessibility.
Suzuki
T
T
Kihara Institute for Biological Research, Yokohama City University, Maioka-cho 641-12, Yokohama 244-0813, Japan.
Yaginuma
M
M
Oishi
T
T
Michishita
E
E
Ogino
H
H
Fujii
M
M
Ayusawa
D
D
D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D000998:Antiviral Agents / Q000494:pharmacology; D001973:Bromodeoxyuridine / Q000494:pharmacology*; D016922:Cellular Senescence / Q000187:drug effects / Q000235:genetics; D002999:Clone Cells / Q000187:drug effects / Q000378:metabolism; D003851:Deoxyribonucleases / Q000187:drug effects / Q000378:metabolism; D004214:Distamycins / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000502:physiology; D020868:Gene Silencing / Q000187:drug effects* / Q000502:physiology; D049452:Green Fluorescent Proteins; D006367:HeLa Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007202:Indicators and Reagents / Q000493:pharmacokinetics; D008164:Luminescent Proteins / Q000493:pharmacokinetics; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D019076:Transgenes / Q000187:drug effects* / Q000235:genetics*
D000964:Antimetabolites, Antineoplastic; D000998:Antiviral Agents; D004214:Distamycins; D007202:Indicators and Reagents; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins; C030000:stallimycin; D003851:Deoxyribonucleases; D001973:Bromodeoxyuridine