Polo-like kinase 1 (PLK1) is a master regulator of mitosis and a well-established driver of cancer progression. Strategies to target PLK1 have largely focused on RNA interference using small interfering RNAs or small-molecule inhibitors. Here, we introduce the direct intracellular targeting of the PLK1 interdomain linking the polo-box domain to the kinase domain using monoclonal antibodies. Three monoclonal antibodies recognizing the interdomain region were delivered into the cytosol of HeLa cells by electroporation. These antibodies were shown to bind PLK1 in living cells and to modulate mechanisms involved in mitotic progression. Our results establish these antibodies as tools to probe PLK1 function through real-time labeling and interference with the mitotic machinery.
Steyer et al. (Thu,) studied this question.