CTCF is a highly conserved, ubiquitously expressed DNA-binding protein that has 
widespread capabilities in gene regulation. CTCF plays important roles in cell 
growth regulatory processes and epigenetic functions. Ectopic expression of CTCF 
results in severe cell growth inhibition at multiple points within the cell 
cycle, indicating that CTCF levels must be stringently monitored. We have 
investigated the subcellular localization of CTCF in detail. Interestingly, we 
observe that CTCF shows a dynamic cell cycle-dependent distribution. 
Immunofluorescent staining reveals that in interphase CTCF is a nuclear protein, 
which is mainly excluded from the nucleolus. Strikingly, CTCF is associated with 
the centrosome during mitosis, especially from metaphase to anaphase. At 
telophase, CTCF dissociates from the centrosome and localizes to the midbody and 
the reformed nuclei. The association of CTCF with centrosomes and the midbody is 
further confirmed by biochemical fractionation. Moreover, subcellular fractions 
of CTCF show cell cycle and organelle-specific posttranslational modifications, 
suggesting different roles for CTCF at different stages of the cell cycle.