53BP2 induces apoptosis through the mitochondrial death pathway.
The p53 binding protein 2 (53BP2) has been identified as the interacting protein to p53, Bcl-2, and p65 subunit of nuclear factor kappaB (NF-kappaB). The TP53BP2 gene encodes two splicing variants, 53BP2S and 53BP2L, previously known as apoptosis stimulating protein 2 of p53 (ASPP2). We found that these 53BP2 proteins are located predominantly in the cytoplasm and induce apoptosis as demonstrated by cleavage of poly ADP ribose polymerase (PARP) and annexin V staining. Furthermore, we demonstrate that 53BP2 is located in the mitochondria and induces apoptosis associated with depression of the mitochondrial trans-membrane potential (DeltaPsim) and activation of caspase-9. From these findings we conclude that 53BP2 induces apoptosis through the mitochondrial death pathway.
Kobayashi
Shinya
S
Department of Molecular and Cellular Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8601, Japan.
Kajino
Shinichi
S
Takahashi
Naoko
N
Kanazawa
Satoshi
S
Imai
Kenichi
K
Hibi
Yurina
Y
Ohara
Hirotaka
H
Itoh
Makoto
M
Okamoto
Takashi
T
D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004441:Ecdysterone / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D008928:Mitochondria / Q000502:physiology*
D051017:Apoptosis Regulatory Proteins; D002352:Carrier Proteins; C090468:TP53BP2 protein, human; D004441:Ecdysterone; C008999:ponasterone A; C506433:CASP9 protein, human; D053453:Caspase 9; D020169:Caspases