NAK is recruited to the TNFR1 complex in a TNFalpha-dependent manner and mediates the production of RANTES: identification of endogenous TNFR-interacting proteins by a proteomic approach.
Tumor necrosis factor alpha (TNFalpha) is a proinflammatory cytokine with pleiotropic immunological and biological activities. TNFalpha signaling is triggered by the engagement of soluble TNFalpha to two types of cell surface receptors, TNFR1 and TNFR2. This recruits cytosolic proteins to the intracellular domains of the receptors and initiates signaling to downstream effectors. In this study, we used a proteomic approach to identify these cytosolic proteins from affinity-purified, endogenous TNFalpha.TNFR complexes in human myelomonocytic U937 cells. Seven proteins were identified, including TRADD, TRAP2, and TRAF2, which are three proteins known to be recruited to TNFalpha receptors. NAK, RasGAP3, TRCP1, and TRCP2 were also identified. We further showed that NAK is recruited to TNFR1 in a temporally regulated and TNFalpha-dependent manner and that it mediates the TNFalpha-induced production of the chemokine RANTES (regulated on activation normal T cell expressed and secreted). These data demonstrate that NAK is a component of the TNFalpha.TNFR1 signaling complex and confirm the physiological role of NAK in the TNFalpha-mediated response.
Department of Inflammation, Wyeth Research, 200 Cambridge Park Dr., Cambridge, MA 02140, USA.
Jun
J
Kuai
Joe
J
Wooters
J Perry
JP
Hall
Vikram R
VR
Rao
Elliott
E
Nickbarg
Bilian
B
Li
Moitreyee
M
Chatterjee-Kishore
Yongchang
Y
Qiu
Lih-Ling
LL
Lin
D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D018946:Chemokine CCL5 / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D047468:Immunoprecipitation; D013058:Mass Spectrometry; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis* / Q000502:physiology*; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D034741:RNA, Small Interfering / Q000378:metabolism; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D020298:U937 Cells
D018946:Chemokine CCL5; D020543:Proteome; D034741:RNA, Small Interfering; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha; D017346:Protein Serine-Threonine Kinases; C403191:TBK1 protein, human