Analysis of candidate antagonists of IAP-mediated caspase inhibition using yeast reconstituted with the mammalian Apaf-1-activated apoptosis mechanism.
We have reconstituted the Apaf-1-activated apoptosis mechanism in Sacchromyces cerevisiae such that the presence of a constitutively active form of Apaf-1 together with both Caspase-9 and Caspase-3 results in yeast death. This system is a good model of the Apaf-1-activated pathway in mammalian cells: MIHA (XIAP/hILP), and to a lesser degree MIHB (c-IAP1/HIAP2) and MIHC (c-IAP-2/HIAP1) can inhibit caspases in this system, and protection by IAPs (inhibitor of apoptosis) can be abrogated by coexpression of the Drosophila pro-apoptotic proteins HID and GRIM or the mammalian protein DIABLO/Smac. Using this system we demonstrate that unlike DIABLO/Smac, other proteins which interact with mammalian IAPs (TAB-1, Zap-1, Traf-1 and Traf-2) do not act to antagonise IAP- mediated caspase inhibition.
Hawkins
C J
CJ
Department of Haematology and Oncology, Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Road, Parkville 3052, Australia. hawkinsc@cryptic.rch.unimelb.edu.au
Silke
J
J
Verhagen
A M
AM
Foster
R
R
Ekert
P G
PG
Ashley
D M
DM
D000818:Animals; D017209:Apoptosis; D053477:Apoptotic Protease-Activating Factor 1; D002352:Carrier Proteins / Q000502:physiology; D053148:Caspase 3; D053453:Caspase 9; D061945:Caspase Inhibitors; D020169:Caspases / Q000502:physiology; D029721:Drosophila Proteins; D051034:Inhibitor of Apoptosis Proteins; D024101:Mitochondrial Proteins / Q000502:physiology; D009479:Neuropeptides / Q000502:physiology; D011506:Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics*; D014162:Transfection; D014764:Viral Proteins / Q000502:physiology; D051636:X-Linked Inhibitor of Apoptosis Protein
D053477:Apoptotic Protease-Activating Factor 1; D002352:Carrier Proteins; D061945:Caspase Inhibitors; D029721:Drosophila Proteins; C108880:HID protein, Drosophila; D051034:Inhibitor of Apoptosis Proteins; D024101:Mitochondrial Proteins; D009479:Neuropeptides; D011506:Proteins; D014764:Viral Proteins; D051636:X-Linked Inhibitor of Apoptosis Protein; C108881:grim protein, Drosophila; C081618:p35 protein, Nucleopolyhedrovirus; D053148:Caspase 3; D053453:Caspase 9; D020169:Caspases