title: The p80 TNF receptor-associated kinase (p80TRAK) associates with residues 354-397 of the p80 cytoplasmic domain: similarity to casein kinase.
abstract: The cytoplasmic domain of the p80 TNF receptor associates with a protein kinase, termed p80TRAK, that phosphorylates both the p60 and p80 TNF receptors. To determine the region of the cytoplasmic domain that is necessary for binding of p80TRAK and the region that it phosphorylates, a series of deletions of the p80 cytoplasmic domain were constructed and expressed as glutathione-S-transferase fusion proteins. These fusions were then used to examine the binding of p80TRAK derived from cellular extracts. We found that out of 174 residues (266-439) in the cytoplasmic domain of p80 receptor, 44 residues (354-397) were sufficient for binding of p80TRAK. Interestingly, this was also the region that contained the phosphorylation site for p80TRAK. Phosphoamino acid analysis of this region revealed phosphorylation primarily on serine residues. Furthermore, we found that, like p80TRAK, purified casein kinase 1 (CK1) also binds to residues 354-397 of the p80 TNF receptor and causes its phosphorylation. Additionally, the activity of p80TRAK was inhibited by CK1-7, the CK1-specific inhibitor. Thus, our results indicate that p80TRAK associates with a short stretch of approximately 44 residues located in the cytoplasmic domain of the p80 TNF receptor and that this kinase is similar to CK1.
authors.affiliation: Department of Molecular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: B G
authors.initials: BG
authors.lastname: Darnay
authors.forename: S
authors.initials: S
authors.lastname: Singh
authors.forename: B B
authors.initials: BB
authors.lastname: Aggarwal
mesh_terms: D015703:Antigens, CD / Q000737:chemistry / Q000378:metabolism*; D047388:Casein Kinases; D003593:Cytoplasm / Q000737:chemistry; D005982:Glutathione Transferase / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D011485:Protein Binding; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000737:chemistry* / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor / Q000737:chemistry / Q000378:metabolism*; D047889:Receptors, Tumor Necrosis Factor, Type II; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D015703:Antigens, CD; D047428:Protein Kinase Inhibitors; D018124:Receptors, Tumor Necrosis Factor; D047889:Receptors, Tumor Necrosis Factor, Type II; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase; D011494:Protein Kinases; C105541:p80TRAK protein; D047388:Casein Kinases