Short Communication Expression of Akt and MAPK in the Normal and Regenerating Peripheral Nerves and Their Dorsal Root Ganglia

PI3K-Akt and Ras-MAPK pathways were both implicated in cell survival and neurite-outgrowth, respectively. Akt has been suggested to be involved in neuronal survival and MAPK in neurite outgrowth during development. This study investigated if Akt, a component of PI3K-Akt pathway, and MAPK/ERK, a component of Ras-MAPK pathway, were expressed in the normal and regenerating dorsal root ganglia and their respective peripheral nerves. Western blot investigations carried out on rodent nerve tissues showed that both phospho-Akt and phospho-MAPK were expressed after axotomy. Therefore, both the phosphoproteins appeared to be important not only during nerve development but also during nerve regeneration.

[1]  P. Lazarovici,et al.  Signaling Pathways for PC12 Cell Differentiation: Making the Right Connections , 2002, Science.

[2]  S. Bartlett,et al.  Anterograde and retrograde transport of active extracellular signal-related kinase 1 (ERK1) in the ligated rat sciatic nerve , 2001, Neuroscience.

[3]  D. Kaplan,et al.  The TrkB-Shc Site Signals Neuronal Survival and Local Axon Growth via MEK and PI3-Kinase , 2000, Neuron.

[4]  H. Kiyama,et al.  Akt/Protein Kinase B Prevents Injury-Induced Motoneuron Death and Accelerates Axonal Regeneration , 2000, The Journal of Neuroscience.

[5]  M. Bähr,et al.  Insulin-Like Growth Factor-I Protects Axotomized Rat Retinal Ganglion Cells from Secondary Death via PI3-K-Dependent Akt Phosphorylation and Inhibition of Caspase-3 In Vivo , 2000, The Journal of Neuroscience.

[6]  F. Miller,et al.  Ras Regulates Sympathetic Neuron Survival by Suppressing the p53-Mediated Cell Death Pathway , 1999, The Journal of Neuroscience.

[7]  L. Rubin,et al.  Activated Phosphatidylinositol 3-Kinase and Akt Kinase Promote Survival of Superior Cervical Neurons , 1997, The Journal of cell biology.

[8]  D. Kaplan,et al.  Signal transduction by the neutrophin receptors , 1997 .

[9]  David R. Kaplan,et al.  Regulation of Neuronal Survival by the Serine-Threonine Protein Kinase Akt , 1997, Science.

[10]  H. Sakagami,et al.  Enhanced gene expression for phosphatidylinositol 3-kinase in the hypoglossal motoneurons following axonal crush. , 1996, Brain research. Molecular brain research.

[11]  M. Crouch,et al.  Retrograde axonal transport of signal transduction proteins in rat sciatic nerve , 1995, Brain Research.