Genetic approaches to ciliate pattern formation: from self-assembly to morphogenesis.

In the cortex of ciliates, thousands of basal bodies, with their associated cytoskeletal appendages and networks, are arranged in an elaborate pattern whose reproduction at division involves complex morphogenetic movements. Genetic analysis demonstrates that pattern formation relies both on local constraints imposed by the pre-existing organization, and on the differential interpretation of inductive signals by different cell territories whose individual developmental properties are reset at each division.