Identification of a nuclear protein that promotes NF-kappaB activation.
Receptor-interacting protein (RIP) is a serine/threonine protein kinase that is critically involved in tumor necrosis factor receptor-1 (TNF-R1)-induced NF-kappaB activation. In a yeast two-hybrid screening for potential RIP-interacting proteins, we identified a novel protein designated as NKAP. Although NKAP interacts with RIP in yeast, NKAP does not interact with RIP in mammalian cells in co-immunoprecipitation experiments. When overexpressed in 293 cells, NKAP activated NF-kappaB in a dose-dependent manner. Moreover, down-regulation of NKAP by antisense RNA significantly inhibited TNF- and IL-1-induced NF-kappaB activation. Immunofluorescent staining indicated that NKAP was localized in the nucleus. Our findings suggest that NKAP is a novel nuclear regulator of TNF- and IL-1-induced NF-kappaB activation.
Chen
Danying
D
Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing, China.
Li
Zhiqin
Z
Yang
Qian
Q
Zhang
Jingbo
J
Zhai
Zhonghe
Z
Shu
Hong-Bing
HB
D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D015153:Blotting, Western; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D003001:Cloning, Molecular; D056970:Co-Repressor Proteins; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004789:Enzyme Activation; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000378:metabolism*; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D011506:Proteins / Q000502:physiology*; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I; D011994:Recombinant Proteins / Q000378:metabolism; D012097:Repressor Proteins; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D020798:Two-Hybrid System Techniques
D015703:Antigens, CD; D056970:Co-Repressor Proteins; D018076:DNA, Complementary; D016328:NF-kappa B; C479077:NKAP protein, human; D009687:Nuclear Proteins; D011506:Proteins; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D011994:Recombinant Proteins; D012097:Repressor Proteins; D008156:Luciferases; C506249:RIPK1 protein, human; D053422:Receptor-Interacting Protein Serine-Threonine Kinases; C506251:Ripk1 protein, mouse