Jak3promoter/reporter constructs and sequence requirements for the activity of theJak3promoter in M1 cells. (A) The coding region of Jak3 was replaced with the coding region of the firefly luciferase gene when a 5.7-kb genomic clone and several 5′ deletion constructs were subcloned into the pGL3-Basic luciferase reporter vector. The 5′ deletion constructs used in the luciferase reporter assays are depicted. Constructs were numbered according to the approximate start of transcription, which is at the 5′-most extent of the Jak3 cDNA described by Gurniak and Berg.³¹  (B) The pGL3-Basic Jak3pr -3805 construct and several 5′ deletion constructs were transiently transfected into M1 cells that were either unstimulated or stimulated with IL-6. Following a 20-hour incubation period, cells were lysed and analyzed for luciferase activity. Relative expression refers to the fold increase in luciferase activity over vector alone. Values expressed are the average of 3 independent experiments plus or minus one standard deviation.