New roles of the Nek9, Nek6, and Nek7 kinases in the centrosome cycle and ciliogenesis

Nek9, Nek6, and Nek7, are NIMA-related protein kinases (Neks) with different functions during the cell cycle. The centrosome cycle is a process associated with the cell cycle, which is crucial for correct chromosome segregation, and in which some of the Nek kinases play a role. At the same time, ciliogenesis is both interconnected with the cell and the centrosome cycle, and it has been proven that some Nek kinases are also involved in it. The aim of this project is to analyse the possibility that the NIMA-related kinases Nek9, Nek6, and Nek7 may have new roles in the control of centrosome cycle and ciliogenesis. This hypothesis is based on previous results from the Cell Cycle and Signaling Group, showing that the knockout of Nek9 in mouse embryo fibroblasts could cause a decrease in the amount and length of the cilia that cells form in G0, and on results publicised by other groups. The experimental approach proposed in this project is based on causing the transient silencing of Nek9, Nek6, and Nek7 expression by siRNA transfection in a human cell line (hTERT RPE-1), and on studying the effects of this in the cilia and centrosomes by immunofluorescence. We concluded that Nek9 and Nek7 silencing may alter the percentage of ciliated cells, while Nek6 depletion results in a significative increase in the average cilia length. In addition, Nek7 downregulation is linked to an increase in the percentage of cells that showed a curvy morphology. Finally, the silencing of any of the three kinases doesn¿t seem to induce centrosome amplification.Peer reviewe