Disruption of the c-JUN-JNK complex by a cell-permeable peptide containing the c-JUN delta domain induces apoptosis and affects a distinct set of interleukin-1-induced inflammatory genes.
The transcription factor activator protein (AP)-1 plays crucial roles in proliferation, cell death, and the immune response. c-JUN is an important component of AP-1, but only very few c-JUN response genes have been identified to date. Activity of c-JUN is controlled by NH2-terminal phosphorylation (JNP) of its transactivation domain by a family of JUN-NH2-terminal protein kinases (JNK). JNK form a stable complex with c-JUN in vitro and in vivo. We have targeted this interaction by means of a cell-permeable peptide containing the JNK-binding (delta) domain of human c-JUN. This peptide strongly and specifically induced apoptosis in HeLa tumor cells, which was paralleled by inhibition of serum-induced c-JUN phosphorylation and up-regulation of the cell cycle inhibitor p21cip/waf. Application of the c-JUN peptide to interleukin (IL)-1-stimulated human primary fibroblasts resulted in up-regulation of four genes, namely COX-2, MnSOD, I kappa B alpha, and MAIL and down-regulation of 10 genes, namely CCL8, mPGES, SAA1, hIAP-1, hIAP-2, pent(r)axin-3, CXCL10, IL-1 beta, ICAM-1, and CCL2. Only a small group of genes, namely pent(r)axin-3, CXCL10, ICAM-1, and IL-1 beta, was inhibited by both the c-JUN peptide and the JNK inhibitor SP600125. Thereby, and by additional experiments using small interfering RNA to suppress endogenous c-JUN we identify for the first time three distinct groups of inflammatory genes whose IL-1-induced expression depends on c-JUN, on JNK, or on both. These results shed further light on the complexity of c-JUN-JNK-mediated gene regulation and also highlight the potential use of dissecting signaling downstream from JNK to specifically target proliferative diseases or the inflammatory response.
Holzberg
David
D
Institute of Pharmacology, Medical School Hannover, Carl-Neuberg Strasse 1, D-30625 Hannover, Germany.
Knight
C Graham
CG
Dittrich-Breiholz
Oliver
O
Schneider
Heike
H
Dörrie
Anneke
A
Hoffmann
Elke
E
Resch
Klaus
K
Kracht
Michael
M
D000595:Amino Acid Sequence; D017209:Apoptosis / Q000187:drug effects*; D001483:Base Sequence; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D066298:In Vitro Techniques; D007249:Inflammation / Q000235:genetics*; D007375:Interleukin-1 / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases; D046911:Macromolecular Substances; D020928:Mitogen-Activated Protein Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D016755:Proto-Oncogene Proteins c-jun / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction; D018808:Transcription Factor AP-1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D018076:DNA, Complementary; D007375:Interleukin-1; D046911:Macromolecular Substances; D010446:Peptide Fragments; D016755:Proto-Oncogene Proteins c-jun; D011994:Recombinant Proteins; D018808:Transcription Factor AP-1; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases