Cooperative interaction of ets-1 with USF-1 required for HIV-1 enhancer activity in T cells.
EMBO J
; 17(6): 1728-39, 1998 Mar 16.
Article
in En
| MEDLINE
| ID: mdl-9501094
ABSTRACT
The distal enhancer region of the human immunodeficiency virus 1 (HIV-1) long terminal repeat (LTR) is known to be essential for HIV replication and to contain immediately adjacent E-box and Ets binding sites. Based on a yeast one-hybrid screen we have identified the E-box binding protein USF-1 as a direct interaction partner of Ets-1 and found that the complex acts on this enhancer element. The binding surfaces of USF-1 and Ets-1 map to their DNA-binding domains and although these domains are highly conserved, the interaction is very selective within the respective protein family. USF-1 and Ets-1 synergize in specific DNA binding as well as in the transactivation of reporter constructs containing the enhancer element, and mutations of the individual binding sites dramatically reduce reporter activity in T cells. In addition, a dominant negative Ets-1 mutant inhibits both USF-1-mediated transactivation and the activity of the HIV-1 LTR in T cells. The inhibition is independent of Ets DNA-binding sites but requires the Ets binding surface on USF-1, highlighting the importance of the direct protein-protein interaction. Together these results indicate that the interaction between Ets-1 and USF-1 is required for full transcriptional activity of the HIV-1 LTR in T cells.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Transcription Factors
/
T-Lymphocytes
/
HIV Enhancer
/
Proto-Oncogene Proteins
/
HIV-1
Type of study:
Prognostic_studies
Limits:
Animals
/
Humans
Language:
En
Journal:
EMBO J
Year:
1998
Document type:
Article
Affiliation country:
Alemania