The asymmetric cell division is a process by which a cell divides in two daughter cells with different fates. Asymmetric cell division is fundamental in animals. In particular for generating various cell types and also for preserving the stem cell pool. During asymmetric cell division, the cell needs to coordinate cell cycle events with cell polarity. Indeed, the polarization of the cell permits the segregation of numerous cell determinants which is essential for the specialization of the cell. The coupling of polarization and cell cycle is finely regulated. However, the mechanisms of the coupling are still not fully understood. The nematode Caenorhabditis elegans is particularly well suited for the study of the links between cell cycle and polarity. The first five cleavages of the zygote are asymmetric and the proteins in action are well conserved across species. Among the actors cross-talking between cell cycle and cell polarity, the mitotic kinase PLK-1 (Polo-Like Kinase 1) plays a role. PLK-1 regulates both cell cycle and cell polarity. The aim of this work is to elaborate tools allowing us to monitor the activity of PLK-1. To achieve this, we focused on using FRET-based biosensors and antibodies. The FRET-based biosensors were developed to follow the PLK-1 spatiotemporal activity in vivo. In addition, an antibody against active form (phosphorylated) of PLK-1 was produced and its specificity was investigated.