Abstract
14-3-3 proteins are ubiquitous proteins highly conserved among eukaryotes. They are involved in the regulation of several cellular processes by modifying the function and the localization of many targeted proteins. FTT-1 and FTT-2 are the two 14-3-3 orthologs identified in C. elegans. We showed that FTT proteins are involved in the main longevity pathway of C. elegans : the AF-2/Insulin/IGF-1-like pathway which also regulates stress resistance and metabolism through the activity of its final effector DAF-16, the ortholog of the Forkhead transcription factor in mammals. This PhD work allowed us to determine the specific functions of each FTT protein in the different phenotypes conferred by this pathway and to highlight the prominent role of FTT-2. Moreover, our data revealed the additional implication of FTT-2 in the regulation of lifespan and lipid metabolism, and the contribution of both FTT proteins in stress resistance, by a mechanism distinct from the DAF-2/Insulin/IGF-1-like pathway and independant of DAF-16. Taking together, our results enhance the complexity of FTT functions and demonstrate their involvement in several processes essential for worms survival, not only under stress conditions, but also during normal aging.