Physical and functional interactions between Daxx and TSG101.
Daxx has been reported to mediate the Fas/JNK-dependent signals in the cytoplasm. However, several evidences have suggested that Daxx is located mainly in the nucleus and functions as a transcriptional regulator. Recently, we identified DMAP1, a TSG101-interacting protein as a Daxx binding partner by yeast two-hybrid screening. TSG101 has been shown to act as transcriptional co-repressor of nuclear hormone receptors. Here we examined whether TSG101also interacts with Daxx directly. The association of Daxx and TSG101 was confirmed using co-expressed tagged proteins. The interaction regions in both proteins were also mapped, and the cellular localization of the interaction was examined. TSG101 formed a complex with Daxx through its coiled-coil domain and co-localized in the nucleus. Furthermore, TSG101 enhanced Daxx-mediated repression of glucocorticoid receptor transcriptional activity. These results provide the novel molecular interactions between Daxx and TSG101, which establish an efficient repressive transcription complex in the nucleus.
Muromoto
Ryuta
R
Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-Ku Kita 12 Nishi 6, Sapporo 060-0812, Japan.
Sugiyama
Kenji
K
Yamamoto
Tetsuya
T
Oritani
Kenji
K
Shimoda
Kazuya
K
Matsuda
Tadashi
T
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D056970:Co-Repressor Proteins; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D056827:Endosomal Sorting Complexes Required for Transport; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D015151:Immunoblotting; D047908:Intracellular Signaling Peptides and Proteins; D008156:Luciferases / Q000378:metabolism; D018832:Molecular Chaperones; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011965:Receptors, Glucocorticoid / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection; D020798:Two-Hybrid System Techniques; D000099177:Tsg101 Protein
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D056970:Co-Repressor Proteins; D004268:DNA-Binding Proteins; D056827:Endosomal Sorting Complexes Required for Transport; D047908:Intracellular Signaling Peptides and Proteins; D008156:Luciferases; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D011965:Receptors, Glucocorticoid; D014157:Transcription Factors; D000099177:Tsg101 Protein; C106985:DAXX protein, human