Fig. 3. Nucleolar localization of human TRF2 in interphase. The colocalization of TRF2 in human MCF-7 cells with Ki-67 protein (A-C), BrdU (D-F), and cyclin B1 (G-I) are shown at different stages of interphase. Arrows in A-C indicate a G0 phase cell that lacks a positive staining of Ki-67. Arrows in D-F indicate S-phase cells displayed by BrdU incorporation. Arrows in G-I indicate G2 phase cells with a high expression of cyclin B1.