AMF-1/Gps2 binds p300 and enhances its interaction with papillomavirus E2 proteins.
The cellular protein AMF-1 (Gps2) positively modulates gene expression by the papillomavirus E2 protein (D. E. Breiding et al., Mol. Cell. Biol. 17:7208-7219, 1997). We show here that AMF-1 also binds the transcriptional coactivator p300 in vitro and in vivo. E2 interacted weakly with p300. These observations led to a model in which AMF-1 recruits p300 into a complex with E2. Cotransfection of AMF-1 or p300 stimulated levels of E2-dependent transcription, while cotransfection of both AMF-1 and p300 showed an additive effect. The functional significance of p300 recruitment for E2 transactivation was evidenced by repression of E2-activated transcription by adenovirus E1A, which inhibits both coactivator and acetylase activities of p300. Antibodies to AMF-1 or E2 immunoprecipitated histone acetylase activity from cell lysates. Western blotting using antibody against acetyl-lysine failed to detect acetylation of AMF-1 or E2 in complex with p300. These results suggest that AMF-1 facilitates the recruitment of p300 and its histone acetylase activity into complexes with E2 and represents a novel mechanism of transcriptional activation.
Peng
Y C
YC
Department of Dermatology, New England Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA.
Breiding
D E
DE
Sverdrup
F
F
Richard
J
J
Androphy
E J
EJ
D000107:Acetylation; D017500:Adenovirus E1A Proteins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D052688:Bovine papillomavirus 1; D002417:Cattle; D002460:Cell Line; D011232:Chemical Precipitation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D018411:Spodoptera / Q000166:cytology; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D017500:Adenovirus E1A Proteins; D004268:DNA-Binding Proteins; C069814:E1 protein, Bovine papillomavirus; C051550:E2 protein, Bovine papillomavirus; C054855:E2 protein, Human papillomavirus type 16; D005656:Fungal Proteins; C103316:GPS2 protein, human; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D009856:Oncogene Proteins, Viral; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D014764:Viral Proteins