Deciphering the mechanisms of developmentally regulated centriole elimination

Descripción del proyecto

Nuevos conocimientos sobre la eliminación del centriolo durante la ovogénesis

Los centriolos son orgánulos celulares que apoyan la formación de cilios y flagelos, que son estructuras de locomoción, así como de los centrosomas. Durante la reproducción sexual, solamente el esperma aporta centriolos al zigoto, mientras que se eliminan los centriolos del oocito. Con todo, todavía se desconoce el mecanismo subyacente a este proceso. El proyecto financiado con fondos europeos CENTEL empleará «Caenorhabditis elegans» para revelar los mecanismos mediante los cuales se eliminan los centriolos durante la ovogénesis. Los investigadores del proyecto aplicarán imagenología «in vivo» y llevarán a cabo un cribado proteómico para identificar los agentes clave de este proceso. Uno de los objetivos principales es revelar la medida en la que se ha conservado evolutivamente la eliminación de los centriolos.

Objetivo

Centrioles are evolutionary conserved organelles that template the formation of cilia, flagella and centrosomes. Centriole number dictates how many such structures form in a cell, so that controlling this number is essential for proper development and health. During sexual reproduction of animals, only the sperm contributes centrioles to the zygote, whereas centrioles are eliminated from the oocyte. The signals initiating and the processes executing centriole elimination remain largely elusive, both during oogenesis and in other developmental contexts where this can occur. Here, I propose to conduct state-of-the art live imaging and use novel quantitative super-resolution approaches in C. elegans to uncover the timing and molecular changes during oogenesis centriole elimination. Moreover, I will decipher the role of the RNA-binding protein CGH-1 in the timing of centriole elimination through a sequencing-based approach. Furthermore, I will conduct a proteomic screen to identify and characterize novel components required for oogenesis centriole elimination in worms. In a complementary approach, I will address the potential evolutionary conservation of centriole elimination mechanisms using the protist N. gruberi, which diverged from C. elegans over a billion years ago. I propose to also analyze in detail the dynamics of the elimination process in this system using deployed molecular markers. Moreover, I will conduct a proteomic screen to identify candidate centriolar proteins directing centriole elimination in N. gruberi. Furthermore, I will develop RNAi-mediated and CRISPR/Cas9 inactivation methods to test the function of candidate proteins in centriole elimination, thus also adding an important item to the toolbox at the disposal of scientists using N. gruberi. Overall, my work is expected to reveal whether centriole elimination is an ancestral mechanisms that has been conserved across eukaryotes and uncover the underlying molecular tenets of this process.