| AJ18 and Krox26 represent novel zinc finger transcription factors involved in osteogenesis. To identify downstream targets of these genes, cell lines were created from the osteogenic MC3T3-E1 line where target gene expression could be regulated by Doxycycline (Dox). While no inducible lines were obtained for Krox26, two clonal cell lines with inducible AJ18 expression were isolated. Since these lines proved to be unstable, RNA for the Affymetrix array studies was prepared from parental MC3T3-E1 cells that had been transiently co-transfected and incubated with or without Dox for 3 and 8 hours. Analyses of the resulting hybridization profiles revealed that 25 genes (16 increased, 9 decreased) and 99 genes (26 increased, 73 decreased) had a 2-fold or greater change at the 3 hour and 8 hour time points, respectively. Further studies into the expression profiles of these genes will aid in illuminating the role of AJ18 in the osteogenic pathway. |
