Fugu promoter analysis in a fish (top minnow) hepatoma cell line (PLHC-1). (A) Schematic representation of the luciferase (Luc) reporter gene constructs. Fugu Epo locus is shown at the top. The transcription start site is shown by an arrow. (B) The luciferase activity of pGL-basic (PGL3-basic) and pGL3-control (PGL3-SV40) vectors transfected into the PLHC-1 cell line. SV40-promoter/enhancer driven pGL3-control vector, which was used as a positive control, showed up to 115-fold increase in the luciferase activity. (C) The luciferase activity of various promoter-luciferase constructs transfected into the PLHC-1 cell line. The level of luciferase activity obtained with various fEpo promoter-luciferase constructs was significantly higher (P < .05) than that of the pGL3-basic vector. (D) The luciferase activity of the various promoter-luciferase constructs under normal conditions (control), in the presence of cobalt chloride (CoCl2), under hypoxic conditions, and under anaerobic conditions. *Significantly different from the corresponding control at P < .05. RLU indicates relative light unit. The data shown are the mean (n = 3) ± standard error of the mean.
