Gel mobility shift experiment involving 5′ c-jun probe and comparing nuclear extracts of H7 parental cells grown in IL-3 versus Bcr-Abl.A54 cells. Equal quantities of nuclear extract from the two cell lines were placed in a gel mobility shift reaction as noted above, without or with the addition of antibody against c-jun or c-fos, or against ATF-2 or junB. Another reaction was performed with each extract along with the inclusion of 100-fold excess of nonradioactive 5′ c-junDNA (self) probe to establish specificity of the band-shift. Note absence of complex (b) in H7 parental cell extracts, and the supershifting/depletion of complex (b) in Bcr-Abl.A54 cells extracts by either antibody against c-jun or c-fos.