Centrioles are cellular organelles made of microtubules that are essential for centrosome, cilia and flagella assembly and as such are involved in a variety of cellular and developmental processes, including cell motility, division and polarity. Centriole biogenesis is first seen during S phase by the appearance of procentrioles that elongate as the cell cycle progresses to reach nearly full length in mitosis. Most mature centrioles in an organism have similar length, yet very little is known on how centriole length control is exerted. The purpose of the current project is to investigate centriole biogenesis, in particular centriole elongation, its kinetics and regulation. We will search for novel molecular players in this process via two complementary approaches. We will perform an RNAi screening of microtubule regulators in mammalian cells and check for their role in centriole elongation. In addition, we will perform pull-down assays using already known molecular players in centriole length control and search for new binding partners by mass spectrometry. These combined approaches will identify novel players in centriole biogenesis that we will further study using in vitro and in vivo (Drosophila) approaches, to better understand their mechanism of action and their relevance to the organism.