Isolation of an AP-1 repressor by a novel method for detecting protein-protein interactions.
Transcription factor AP-1 transduces environmental signals to the transcriptional machinery. To ensure a quick response yet maintain tight control over AP-1 target genes, AP-1 activity is likely to be negatively regulated in nonstimulated cells. To identify proteins that interact with the Jun subunits of AP-1 and repress its activity, we developed a novel screen for detecting protein-protein interactions that is not based on a transcriptional readout. In this system, the mammalian guanyl nucleotide exchange factor (GEF) Sos is recruited to the Saccharomyces cerevisiae plasma membrane harboring a temperature-sensitive Ras GEF, Cdc25-2, allowing growth at the nonpermissive temperature. Using the Sos recruitment system, we identified new c-Jun-interacting proteins. One of these, JDP2, heterodimerizes with c-Jun in nonstimulated cells and represses AP-1-mediated activation.
Aronheim
A
A
Department of Pharmacology, Program in Biomedical Sciences, School of Medicine, University of California, San Diego, La Jolla 92093-0636, USA.
Zandi
E
E
Hennemann
H
H
Elledge
S J
SJ
Karin
M
M
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D018797:Cell Cycle Proteins; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D005821:Genetic Techniques; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019869:Phosphatidylinositol 3-Kinases; D010749:Phosphoprotein Phosphatases; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D011485:Protein Binding; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D012097:Repressor Proteins / Q000302:isolation & purification* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects*; D020666:ras-GRF1
D018797:Cell Cycle Proteins; C491386:Jundp2 protein, mouse; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D012097:Repressor Proteins; D018808:Transcription Factor AP-1; D020666:ras-GRF1; D019869:Phosphatidylinositol 3-Kinases; D017853:Phosphotransferases (Alcohol Group Acceptor); D010749:Phosphoprotein Phosphatases