Centriole elimination duringC. elegansoogenesis initiates with loss of the central tube protein SAS-1

Abstract

SUMMARYCentrioles are lost during oogenesis in most metazoans, ensuring that the zygote is endowed with the correct number of two centrioles, which are paternally contributed. How centriole architecture is dismantled during oogenesis is not understood. Here, we analyze with unprecedent detail the ultrastructural and molecular changes during oogenesis centriole elimination inC. elegans. Centriole elimination begins with loss of the so-called central tube and organelle widening, followed by microtubule disassembly. The resulting cluster of centriolar proteins then disappears gradually, usually moving in a microtubule- and dynein-dependent manner to the plasma membrane. Moreover, we find that neither Polo-like kinases nor the PCM, which modulate oogenesis centriole elimination inDrosophila, do so inC. elegans. Furthermore, we demonstrate that the central tube protein SAS-1 normally departs first from the organelle, which loses integrity earlier insas-1mutants. Overall, our work provides novel mechanistic insights regarding the fundamental process of oogenesis centriole elimination.