Identification of new tyrosine phosphorylated proteins in rat brain mitochondria.

Reversible protein-phosphorylation is emerging as a key player in the regulation of mitochondrial functions. In particular tyrosine phosphorylation represents a promising field to highlight new mechanisms of bioenergetic regulation. Utilizing immunoaffinity enrichment of phosphotyrosine-containing peptides coupled to mass spectrometric analysis we detected new tyrosine phosphorylated proteins in rat brain mitochondria after peroxovanadate treatment. By bioinformatic predictions we provide suggestions about the potential role of tyrosine phosphorylation in mitochondrial physiology. Our results indicate a primary role of tyrosine phosphorylation in regulating energy production at the mitochondrial level. Moreover, tyrosine phosphorylation might regulate the mitochondrial membrane permeability targeting protein complexes containing ADP/ATP translocase, VDAC, creatine kinase and hexokinase.