Fig. 7. The CENP-A N-terminal tail is required for the recruitment of CENP-C to ectopic sites. A DNA construct encoding the C-terminal core domain of CENP-A with an HA-epitope tag (referred to as CENP-A-core) was transiently transfected into HeLa cells and detected by immunofluorescence using anti-HA antibody. Cells were grown and processed on coverslips. CENP-C was co-stained with a specific antibody. (A) Anti-CENP-C staining is centromere-specific in untransfected control cells (cell on right), in which CENP-A-core expression was undetectable. Similarly, CENP-C localization remained centromere-specific in transfected cells (cell on left), which demonstrated the localization of CENP-A-core throughout the nucleus and most predominately at centromeres. DNA was counterstained with DAPI. (B) Cells expressing the CENP-A-core peptide appeared to progress through mitosis normally. As during interphase, CENP-C was found exclusively at centromeres. The core domain of CENP-A appears to be targeted to chromatin less efficiently than the full-length protein and some accumulations were observed in the cytoplasm (Sullivan et al., 1994). Bars, 10 µm.