title: Auxin-induced rapid degradation of inhibitor of caspase-activated DNase (ICAD) induces apoptotic DNA fragmentation, caspase activation, and cell death: a cell suicide module.
abstract: Caspase-activated DNase (CAD) is a major apoptotic nuclease, responsible for DNA fragmentation and chromatin condensation during apoptosis. CAD is normally activated in apoptosis as a result of caspase cleavage of its inhibitory chaperone ICAD. Other aspects of CAD regulation are poorly understood. In particular, it has been unclear whether direct CAD activation in non-apoptotic living cells can trigger cell death. Taking advantage of the auxin-inducible degron (AID) system, we have developed a suicide system with which ICAD is rapidly degraded in living cells in response to the plant hormone auxin. Our studies demonstrate that rapid ICAD depletion is sufficient to activate CAD and induce cell death in DT40 and yeast cells. In the vertebrate cells, ectopic CAD activation triggered caspase activation and subsequent hallmarks of caspase-dependent apoptotic changes, including phosphatidylserine exposure and nuclear fragmentation. These observations not only suggest that CAD activation drives apoptosis through a positive feedback loop, but also identify a unique suicide system that can be used for controlling gene-modified organisms.
authors.affiliation: From the Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom, kumiko.samejima@ed.ac.uk.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Samejima
authors.affiliation: From the Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Ogawa
authors.affiliation: From the Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Ageichik
authors.affiliation: the Mayo Clinic, Rochester, Minnesota 55905.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Peterson
authors.affiliation: the Mayo Clinic, Rochester, Minnesota 55905.
authors.forename: Scott H
authors.initials: SH
authors.lastname: Kaufmann
authors.affiliation: the Centre for Frontier Research, National Institute of Genetics, ROIS, and Department of Genetics, SOKENDAI, Yata 1111, Mishima, Shizuoka 411-8540, Japan, and the Japan Science and Technology Agency (JST), PREST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Masato T
authors.initials: MT
authors.lastname: Kanemaki
authors.affiliation: From the Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, Scotland, United Kingdom, bill.earnshaw@ed.ac.uk.
authors.forename: William C
authors.initials: WC
authors.lastname: Earnshaw
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D020169:Caspases / Q000378:metabolism*; D016923:Cell Death; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D002645:Chickens; D053938:DNA Fragmentation; D003851:Deoxyribonucleases / Q000378:metabolism*; D004789:Enzyme Activation; D019084:Fluorescent Antibody Technique, Indirect; D015971:Gene Expression Regulation, Enzymologic; D055786:Gene Knockout Techniques; D007210:Indoleacetic Acids / Q000378:metabolism*; D010718:Phosphatidylserines / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology
chemical_list: D017304:Annexin A5; D051017:Apoptosis Regulatory Proteins; D007210:Indoleacetic Acids; D010718:Phosphatidylserines; C109664:caspase-activated DNase inhibitor; D003851:Deoxyribonucleases; D020169:Caspases
keywords: Annexin V; Apoptosis; Auxin; Caspase; Caspase-activated DNase (CAD); Cell Death; DNA Fragmentation; Inhibitor of Caspase-activated DNase (ICAD); TUNEL Assay; Yeast