The compound targeted the protein kinase C-alpha, one of a family of 13 known proteins that relay information from one to another.

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Peroxynitrites contribute to the hyperphosphorylation of tau proteins by oxidating g-protein coupled receptors and trysoine kinase receptors preventing protein kinase C and AKT from inactivating the enzyme GSK3 which is necessary to prevent the hyperphosphorylation of tau proteins.

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Professor Seth Grant, an expert in the molecular mechanism of learning and memory at Edinburgh University, told BBC News Online that PKM was a particular version of an enzyme called protein kinase C (PKC) that had long been implicated in learning.

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