[The sequence of the human PrP gene Exon I and its upstream segment has promoter-like activity].
OBJECTIVE
The human PrP gene locates at the short-arm of the 20th chromosome. This article is was to map the promoter that transcribes the human PrP gene.


METHODS
The sequence of the human PrP gene Exon I and its upstream segment were amplified using PCR, and inserted into a CAT reporter plasmid pBL-CAT6 after sequence analysis. The values of the relative CAT expression under the control of this fragment were evaluated after transiently transfected into HeLa, COS7 and Sh-sy5y cell lines. The amounts of transcription activator SP1 in these three cell lines were calculated with band-shift assays.


RESULTS
Analysis of the human PrP gene Exon I and its upstream segment showed a GC rich sequence, with several potential SP1 binding sites, but without any TATA-box. Under the control of this fragment, the CAT expressions were 2-3 folds increased in transient transfection. Quantity band-shift assays revealed that SP1 was enriched in HeLa cells, but undetectable in COS7 and Sh-sy5y cells.


CONCLUSIONS
The sequence of the human PrP gene Exon I and its upstream segment functions as a promoter-like sequence, probably being as a weak TATA-less promoter. Cells derived from different tissues contain different amount of SP1. The activity of this promoter-like sequence seems to be independent of SP1 presence.
Sun
X
X
Institute of Virology, Chinese Academy of Preventive Medicine, Beijing 100052, China.
Dong
X
X
Zhou
W
W
D002460:Cell Line; D005091:Exons / Q000235:genetics*; D006801:Humans; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011328:Prions / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000032:analysis; D024363:Transcription Initiation Site; D014158:Transcription, Genetic; D014162:Transfection
D011328:Prions; D016329:Sp1 Transcription Factor