One of the main post-translational modifications which tau protein undergoes during neurodegeneration is its endogenous proteolysis, with two truncations described at carboxyl terminal domain (Asp421 and Glu391 truncations). Using in vitro cell models, it has been found that the expression of these truncated tau species produces morphological and functional alterations on different intracellular organelles. Recently a third truncation at carboxyl terminal of tau was described in the neuropathology by Caspase-2 proteolysis at Asp314 residue; however, its possible cytotoxic effects are still unknown. In the present project, the plasmids for Tau 1-314 were generated and expressed in the SH-SY5Y neuronal cell line to evaluate their endogenous protein expression by mass spectrometry. Tau 1-314 induced overexpression of proteins, and altering membrane proteins and related to degradation systems, nucleotide synthesis and DNA repair pathways.