Dekoter, R.P., Schweitzer, B.L., Kamath, M.B., Jones, D., Tagoh, H., Bonifer, C., Hildeman, D.A., and Huang, K.J.
Notes: The interleukin-7 receptor is composed of γ and α subunits, encoded by the genes il7rg and il7r, respectively. The α subunit is expressed in developing B cells and is downregulated upon maturation. These authors investigated the mechanisms of transcriptional regulation of the il7r gene using 5´ RACE, EMSA, RNA interference and chromatin immunoprecipitation analyses. Potential promoter regions identified by 5´ RACE analysis were cloned into the pGL3-Basic luciferase reporter vector for further study. The promoter constructs were transiently transfected into the 38B9 pro-B cell line along with the control pRL-TK Vector, which expresses Renilla luciferase, and the Dual-Luciferase® Reporter Assay System was used to assess luciferase activity from the various promoter constructs. The promoter construct having the highest activity was chosen, and site directed mutagenesis was used to identify specific regions within the promoter fragment that may be important for activity. Sequence analysis was then used to identify a conserved Ets transcription factor binding site within the putative il7r promoter region. To determine whether the ETS transcription factor GABP binds to this Ets region, the authors performed chromatin immunoprecipitation analysis with an anti-GABP antibody. Immunoprecipitated DNA was then PCR-amplified with primers specific for the Ets region or control primers. The Wizard® SV Gel and PCR Clean-Up System was used to purify the amplified fragments prior to semiquantitative PCR analysis. (3626)