FIG. 1.

Multiple CBE-binding complexes exist in mammalian cells. Nuclear extracts were prepared from various cell lines and tissues (as indicated at the top) and subjected to EMSA with a ³²P-labeled CBE probe. A 100-fold excess of unlabeled CBE probe (lane 2) or mutant CBE probe M4 (lane 3) was used to compete (Comp.) for the formation of specific complexes. Multiple binding complexes are categorized as slow-migrating (S) and fast-migrating (F′) groups. Each group is composed of at least two to three complexes. Thy, thymocytes; Spl., splenocytes.