Receptor interacting protein is ubiquitinated by cellular inhibitor of apoptosis proteins (c-IAP1 and c-IAP2) in vitro.
Receptor interacting protein (RIP) is recruited to tumor necrosis factor-alpha receptor 1 (TNFR1) complex upon stimulation and plays a crucial role in the receptor-mediated NF-kappaB activation. Among the components of the TNFR1 complex are proteins that possess ubiquitin-protein isopeptide ligase (E3) activities, such as TNFR1-associated factor 2 (TRAF2), cellular inhibitor of apoptosis proteins (c-IAPs) namely, c-IAP1 and c-IAP2. Here, we showed that ectopically expressed RIP is ubiquitinated, and either the intermediate or death domain of RIP is required for this modification. Expression of c-IAP1 and c-IAP2 decreased the steady-state level of RIP, which was blocked by inhibition of the 26S proteasome. RIP degradation requires intact c-IAP2 containing the RING domain. Our in vitro ubiquitination assay revealed that while TRAF2 had no effect, both c-IAP1 and c-IAP2-mediated RIP ubiquitination with similar efficiency, indicating that c-IAPs can function as E3 toward RIP.
Park
Sun-Mi
SM
Protein Network Research Center, Yonsei University, 134 Shinchon-dong, Seodaemoon-gu, Seoul 120-749, Republic of Korea.
Yoon
Jong-Bok
JB
Lee
Tae H
TH
D000818:Animals; D017209:Apoptosis; D000075747:Baculoviral IAP Repeat-Containing 3 Protein; D002460:Cell Line; D017353:Gene Deletion; D006801:Humans; D015151:Immunoblotting; D051034:Inhibitor of Apoptosis Proteins; D051379:Mice; D014176:Protein Biosynthesis; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D025801:Ubiquitin / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism
D051034:Inhibitor of Apoptosis Proteins; D011506:Proteins; D018124:Receptors, Tumor Necrosis Factor; D011994:Recombinant Proteins; D025801:Ubiquitin; C494833:BIRC2 protein, human; D000075747:Baculoviral IAP Repeat-Containing 3 Protein; C494834:Birc2 protein, mouse; C494835:Birc3 protein, mouse; D044767:Ubiquitin-Protein Ligases; C506249:RIPK1 protein, human; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; C506251:Ripk1 protein, mouse