title: Properties of DNA fragmentation activity generated by ATP depletion.
abstract: Internucleosomal DNA fragmentation is generally perceived as one of the characteristic features of apoptosis, most of which are driven by caspase activation dependent upon ATP. On the other hand, ATP depletion has been reported to induce apoptosis accompanying DNA fragmentation. To address this apparent paradox, we analyzed the DNA-fragmenting activity generated in ATP-depleted cells. In HL-60 promyelocytic leukemia cells cultured in glucose-free medium with oligomycin, internucleosomal DNA fragmentation occurred as an early event. The DNA fragmentation was blocked by serine protease inhibitors but not by caspase inhibitors. Consistently, ICAD/DFF45 could not inhibit the DNA-fragmenting activity of the ATP-depleted cytosol in a cell-free system. When ATP was supplied to the cell-free assay, 80% of the DNA-fragmenting activity was lost. The reduced activity was then restored by proteasome inhibitors, suggesting a role of proteasome to protect from a cellular insult derived from ATP-depletion.
authors.affiliation: Department of Molecular Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, 840 Murodo-cho, Izumi, Osaka 594-1101, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Wada
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D051017:Apoptosis Regulatory Proteins; D001483:Base Sequence; D061945:Caspase Inhibitors; D002474:Cell-Free System; D003546:Cysteine Endopeptidases / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D003600:Cytosol / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D003851:Deoxyribonucleases / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D009097:Multienzyme Complexes / Q000378:metabolism; D009707:Nucleosomes / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology
chemical_list: D051017:Apoptosis Regulatory Proteins; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D017931:DNA Primers; D047908:Intracellular Signaling Peptides and Proteins; D009097:Multienzyme Complexes; D009707:Nucleosomes; D011506:Proteins; D015842:Serine Proteinase Inhibitors; C109664:caspase-activated DNase inhibitor; D000255:Adenosine Triphosphate; D003851:Deoxyribonucleases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex