Re: what are centrioles made of?

Centrioles are quite complex organelles (for a detailed description see: http://cellbio.utmb.edu/cellbio/cilia.htm ).

They are composed primarily of the microtubule subunit proteins tubulin, together with a significant number of other, accessory proteins. In a different incarnation, they function as "basal bodies" to nucleate the assembly of eukaryotic cilia and flagella. As centrioles, their function is less clear, but apparently involved in the organization of the "pericentriolar material" that form the microtubule organizing center (MTOC), which acts to nucleate the assembly of microtubules within the cell.