Nuclear localization of the HCF-1N subunit through association with the HCF-1C subunit, visualized by Immunofluorescence of transfected 293 cells using the αHA (A, D, and E) or αT7 (B and C) primary antibody. Cells were transfected with plasmids pCGNHCF-1N (A), pCGTHCF-1C (B), pCGTHCF-1CΔNLS (C), pCGNHCF-1N1011 and pCGTHCF-1C (D), and pCGNHCF-1N1011 and pCGTHCF-1CΔNLS (E). For comparison, mock-transfected cells were probed with αHCF-M2 (αendog. HCFC [F]), a monoclonal antibody against HCF-1 (28).