Immunofluorescence staining of PLK1 in HeLa cells. Cells were fixed with 4% PFA, blocked with 10% serum, and then incubated with PLK1 Polyclonal Antibody (Product # PA5-81241, 1:1,000)(Figure A) or PLK1 Polyclonal Antibody and antigen (Figure B) at 4°C overnight. Then cells were stained with the Alexa Fluor®488-conjugated Goat Anti-rabbit IgG secondary antibody (green) and counterstained with DAPI (blue). Positive staining was localized to nucleus.