Fig. 3.

Promoter activity in the 5′ flanking region of mouse cp27 gene. A, schematic representation of promoter-reporter plasmids. 1993bp DNA and 5′-truncated fragments of the CP27 promoter upstream of the preferred transcription start site were inserted into the luciferase reporter vector pGL3-Basic in sense orientation. The arrow indicates the preferred transcription start site. The name of each reporter construct was assigned according to the 5′-end nucleotide number and the inserted promoter sequence. All constructs contain a partial exon 1. B, Luciferase activity resulting from the expression of the CP27 promoter-reporter gene constructs. The promoter-reporter gene constructs were transfected into NIH 3T3 cells, and specific luciferase activity was measured 48 hours post transfection. The results were normalized by co-transfection with a pRL-TK reporter plasmid. Error bars represent the standard error for three samples in five independent experiments. The activity of the pGL3-Basic vector transfected in the same experiment is indicated.