title: Inhibitor of apoptosis (IAP)-like protein lacks a baculovirus IAP repeat (BIR) domain and attenuates cell death in plant and animal systems.
abstract: A novel Arabidopsis thaliana inhibitor of apoptosis was identified by sequence homology to other known inhibitor of apoptosis (IAP) proteins. Arabidopsis IAP-like protein (AtILP) contained a C-terminal RING finger domain but lacked a baculovirus IAP repeat (BIR) domain, which is essential for anti-apoptotic activity in other IAP family members. The expression of AtILP in HeLa cells conferred resistance against tumor necrosis factor (TNF)-α/ActD-induced apoptosis through the inactivation of caspase activity. In contrast to the C-terminal RING domain of AtILP, which did not inhibit the activity of caspase-3, the N-terminal region, despite displaying no homology to known BIR domains, potently inhibited the activity of caspase-3 in vitro and blocked TNF-α/ActD-induced apoptosis. The anti-apoptotic activity of the AtILP N-terminal domain observed in plants was reproduced in an animal system. Transgenic Arabidopsis lines overexpressing AtILP exhibited anti-apoptotic activity when challenged with the fungal toxin fumonisin B1, an agent that induces apoptosis-like cell death in plants. In AtIPL transgenic plants, suppression of cell death was accompanied by inhibition of caspase activation and DNA fragmentation. Overexpression of AtILP also attenuated effector protein-induced cell death and increased the growth of an avirulent bacterial pathogen. The current results demonstrated the existence of a novel plant IAP-like protein that prevents caspase activation in Arabidopsis and showed that a plant anti-apoptosis gene functions similarly in plant and animal systems.
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Woe Yeon
authors.initials: WY
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Sun Yong
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Jung
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Ho Byoung
authors.initials: HB
authors.lastname: Chae
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Ganesh M
authors.initials: GM
authors.lastname: Nawkar
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Mi Rim
authors.initials: MR
authors.lastname: Shin
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Park
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Chang Ho
authors.initials: CH
authors.lastname: Kang
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Yong Hun
authors.initials: YH
authors.lastname: Chi
authors.affiliation: National Academy of Agricultural Science, RDA, Suwon 441-856, Korea.
authors.forename: Il Pyung
authors.initials: IP
authors.lastname: Ahn
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Dae Jin
authors.initials: DJ
authors.lastname: Yun
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea.
authors.forename: Kyun Oh
authors.initials: KO
authors.lastname: Lee
authors.affiliation: Department of Molecular and Cellular Biochemistry, College of Medicine, Kangwon National University, Chunchon, Korea.
authors.forename: Young-Myeong
authors.initials: YM
authors.lastname: Kim
authors.affiliation: National Academy of Agricultural Science, RDA, Suwon 441-856, Korea; College of Pharmacy, Gyeongsang National University, Jinju 660-751, Korea. Electronic address: mgk1284@gnu.ac.kr.
authors.forename: Min Gab
authors.initials: MG
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Jinju, 660-701, Korea. Electronic address: sylee@gnu.ac.kr.
authors.forename: Sang Yeol
authors.initials: SY
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D017360:Arabidopsis / Q000235:genetics*; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D053148:Caspase 3 / Q000378:metabolism; D016923:Cell Death; D002470:Cell Survival; D004247:DNA / Q000235:genetics; D037341:Fumonisins / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified / Q000235:genetics; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D037341:Fumonisins; D051034:Inhibitor of Apoptosis Proteins; C056933:fumonisin B1; D004247:DNA; D053148:Caspase 3