[
Bioessays,
2007]
Centriole duplication has been an area of interest since the late 1800s when Boveri suggested that these structures were central organizers for mitosis and cell division. Two groups12 have delineated a linear pathway for centriole assembly. In C. elegans, Pelletier and coworkers1 have identified intermediates in the pathway using cryo-electron tomography. Surprising, the first intermediate is a hollow tube of 60 nm that increases in diameter and then elongates before acquiring microtubules. Similar structures have not been observed to date in other centrioles.