Figure 5.

Luciferase activity of different constructs of the genomic 5′ region of murine SOCS-3. Different constructs were obtained as described in Materials and Methods. After transient transfection, luciferase activity of each construct was measured in untreated (filled bars) and LIF-stimulated (empty bars) AtT-20 cells. Relative luciferase activity was normalized to the activity of pGL3Basic alone in untreated AtT-20 cells, which was defined as 1.0. Crossed lines indicate deletions of STAT binding elements in clones 6D1 and 6D2, in between the named nucleotides. Dotted line indicates a mutation of the wt STAT binding sequence (5′-TTCCAGGAA-3′) with mutant (5′-ATCGACGAT-3′) in clone 6M1.