Mitochondrion 2014-07-01

ERK-mediated phosphorylation of TFAM downregulates mitochondrial transcription: implications for Parkinson's disease.

Kent Z Q Wang, Jianhui Zhu, Ruben K Dagda, Guy Uechi, Salvatore J Cherra, Aaron M Gusdon, Manimalha Balasubramani, Charleen T Chu

Index: Mitochondrion 17 , 132-40, (2014)

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Abstract

Mitochondrial transcription factor A (TFAM) regulates mitochondrial biogenesis, which is downregulated by extracellular signal-regulated protein kinases (ERK1/2) in cells treated chronically with the complex I inhibitor 1-methyl-4-phenylpyridinium (MPP+). We utilized mass spectrometry to identify ERK1/2-dependent TFAM phosphorylation sites. Mutation of TFAM at serine 177 to mimic phosphorylation recapitulated the effects of MPP+ in decreasing the binding of TFAM to the light strand promoter, suppressing mitochondrial transcription. Mutant TFAM was unable to affect respiratory function or rescue the effects of MPP+ on respiratory complexes. These data disclose a novel mechanism by which ERK1/2 regulates mitochondrial function through direct phosphorylation of TFAM. Copyright © 2014 Elsevier B.V. and Mitochondria Research Society. All rights reserved.