Deciphering the dual role of Sirtuin

[eng] OBJECTIVES: Class IV sirtuins are dual sirtuins that possess deacetylation and ADP-ribosylation activities. The main objective of this PhD was to study of sirtuin duality. Specifically, we focused our attention on the ADPRT actovoty, and its interplay with the deacetylation activity, and the contribution of OAADPr in the process. In order to address this purpose, the following objectives have been developed: 1. Characterization of O-Acetyl ADP-ribosylation as a new Post-Translational modification. 2. Study the functional implications that SIRT7 ADPRT and OAADPRT activities. 3. Determine the in vivo contribution of SIRT7 ADPRT/OAADPRT activity in a ADPRT/OAADPRT-defective SIRT7N189Q knock-in mouse model.