title: Cadmium and zinc mediated changes of the Ca(2+)-dependent endonuclease in apoptosis.
abstract: Isolated nuclei from mammalian cells contain a Ca(2+)-dependent endonuclease [1]. The produced DNA fragmentation is a necessary step in the sequence of events resulting in apoptosis [2]. We report here that zinc inhibits the DNA fragmentation in dependence of the free Ca2+ concentrations, suggesting that a balance between zinc and calcium might regulate the Ca(2+)-dependent endonuclease. Incubation of nuclei with different free calcium concentrations combined with cadmium shows a stronger inhibition of the DNA fragmentation than zinc. Cadmium inhibits the endonuclease in a calcium-independent way. Surprisingly cadmium alone is able to stimulate the endonuclease, thus to replace Ca2+.
authors.affiliation: Department of Biology and Chemistry, University of Bremen, Germany.
authors.forename: R D
authors.initials: RD
authors.lastname: Lohmann
authors.forename: D
authors.initials: D
authors.lastname: Beyersmann
mesh_terms: D000818:Animals; D002104:Cadmium / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D016923:Cell Death; D002467:Cell Nucleus / Q000378:metabolism; D004249:DNA Damage; D004706:Endodeoxyribonucleases / Q000378:metabolism*; D066298:In Vitro Techniques; D008099:Liver / Q000166:cytology; D008628:Mercury / Q000494:pharmacology; D013950:Thymus Gland / Q000166:cytology; D015032:Zinc / Q000494:pharmacology*
chemical_list: D002104:Cadmium; D004706:Endodeoxyribonucleases; D008628:Mercury; D015032:Zinc; D002118:Calcium