The tumor necrosis factor-related apoptosis-inducing ligand receptors TRAIL-R1 and TRAIL-R2 have distinct cross-linking requirements for initiation of apoptosis and are non-redundant in JNK activation.
Overexpression of the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptors, TRAIL-R1 and TRAIL-R2, induces apoptosis and activation of NF-kappaB in cultured cells. In this study, we have demonstrated differential signaling capacities by both receptors using either epitope-tagged soluble TRAIL (sTRAIL) or sTRAIL that was cross-linked with a monoclonal antibody. Interestingly, sTRAIL was sufficient for induction of apoptosis only in cell lines that were killed by agonistic TRAIL-R1- and TRAIL-R2-specific IgG preparations. Moreover, in these cell lines interleukin-6 secretion and NF-kappaB activation were induced by cross-linked or non-cross-linked anti-TRAIL, as well as by both receptor-specific IgGs. However, cross-linking of sTRAIL was required for induction of apoptosis in cell lines that only responded to the agonistic anti-TRAIL-R2-IgG. Interestingly, activation of c-Jun N-terminal kinase (JNK) was only observed in response to either cross-linked sTRAIL or anti-TRAIL-R2-IgG even in cell lines where both receptors were capable of signaling apoptosis and NF-kappaB activation. Taken together, our data suggest that TRAIL-R1 responds to either cross-linked or non-cross-linked sTRAIL which signals NF-kappaB activation and apoptosis, whereas TRAIL-R2 signals NF-kappaB activation, apoptosis, and JNK activation only in response to cross-linked TRAIL.
Mühlenbeck
F
F
Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany.
Schneider
P
P
Bodmer
J L
JL
Schwenzer
R
R
Hauser
A
A
Schubert
G
G
Scheurich
P
P
Moosmayer
D
D
Tschopp
J
J
Wajant
H
H
D000911:Antibodies, Monoclonal / Q000276:immunology; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D004789:Enzyme Activation; D005434:Flow Cytometry; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D015850:Interleukin-6 / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases; D008562:Membrane Glycoproteins / Q000819:agonists / Q000276:immunology / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D011940:Receptor Aggregation; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000819:agonists / Q000378:metabolism*; D015398:Signal Transduction; D013205:Staphylococcal Protein A / Q000276:immunology; D053221:TNF-Related Apoptosis-Inducing Ligand; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000819:agonists / Q000276:immunology / Q000378:metabolism
D000911:Antibodies, Monoclonal; D051017:Apoptosis Regulatory Proteins; D007074:Immunoglobulin G; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D013205:Staphylococcal Protein A; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases