Proteomic Analysis of PP2A Mutants and PP2A-related Tumor Virus Proteins

Protein phosphatase 2A (PP2A) is a tumor suppressor, whose function and activity is influenced by mutations of PP2A subunits and PP2A-related tumor virus proteins. In this work, protein-protein interaction changes in the normal PP2A interaction network caused by mutations of PP2A scaffolding A (PPP2R1A) and catalytic C (PPP2CA) subunits have been characterized by AP-SWATH. The results show that the normal function and activity of PP2A holoenzyme may be significantly altered and influenced by these mutations. This study also characterizes the interactomes of several PP2A-related tumor viral oncoproteins, including E4orf4. It is revealed for the first time that ASPP-PP1 complex subunits are among the major interactors of E4orf4, suggesting the involvement of E4orf4 in the regulation of Hippo signaling pathway. The results gained in my M.Sc. work provide a deeper understanding of the consequences of PP2A subunits mutations and the PP2A-dependent and PP2A-independent functions of the PP2A-related tumor virus proteins.M.Sc.2018-04-14 00:00:0