Repression of a herpes simplex virus immediate-early promoter by the Oct-2 transcription factor is dependent on an inhibitory region at the N terminus of the protein.
The B-cell form of the Oct-2 transcription factor Oct 2.1 can activate the herpes simplex virus immediate-early gene 3 (IE3) promoter, whereas the neuronally expressed Oct 2.4 and 2.5 forms of the protein, which contain a different C terminus, can repress this promoter. Here we show that partial or full deletion of the C terminus of Oct 2.1 in the presence of an intact N terminus results in a protein which can strongly repress the IE3 promoter. In contrast, deletion of the entire N terminus or a short region within it leaving the C terminus intact results in a very strong activator. Deletion of both N and C termini leaving only the isolated POU domain generates only a very weak repressor. The N-terminal region defined in this way can repress a heterologous promoter when linked to the DNA-binding domain of the GAL4 factor, indicating that it can function as an independent inhibitory domain. These results indicate that a specific region within the N terminus common to Oct 2.1, 2.4, and 2.5 plays a critical role in the ability of neuronally expressed forms of Oct-2 to repress the IE3 promoter but can do so only when the C-terminal region of Oct 2.1 is altered or deleted.
Lillycrop
K A
KA
Department of Molecular Pathology, University College London Medical School, United Kingdom.
Dawson
S J
SJ
Estridge
J K
JK
Gerster
T
T
Matthias
P
P
Latchman
D S
DS
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics; D004268:DNA-Binding Proteins; D005814:Genes, Viral; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D017384:Sequence Deletion; D018139:Simplexvirus / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
D004279:DNA, Viral; D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D015500:Chloramphenicol O-Acetyltransferase