ATF3 enhances c-Jun-mediated neurite sprouting.

Andree G Pearson; Carol W Gray; John F Pearson; Jeffrey M Greenwood; Matthew J During; Michael Dragunow

doi:10.1016/j.molbrainres.2003.09.014

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ATF3 enhances c-Jun-mediated neurite sprouting.

Andree G Pearson·Carol W Gray·John F Pearson·Jeffrey M Greenwood·Matthew J During·Michael Dragunow

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Abstract

The AP-1 transcription factor c-Jun is induced in axotomized neurons of the peripheral and central nervous systems, and in both cases upregulation of c-Jun expression has been correlated with axonal regeneration. More recently there has been interest in the c-Jun-related bZIP transcription factor, ATF3, and its function in neurons. ATF3 is also induced in nerve cells in response to axotomy and there is a correlation between increased ATF3 expression and upregulation of c-Jun in surviving neurons. Moreover, c-Jun is able to induce expression of ATF3. We investigated the effect of co-expressing c-Jun and ATF3 in two neuronal-like cell lines to model transcriptional events occurring in axotomized neurons undergoing regeneration. We show that expression of ATF3 with c-Jun significantly enhances c-Jun-mediated neurite sprouting, and that this phenotype is most likely mediated by a physical association of these two transcription factors. Our results suggest that a program of axonal regeneration is initiated when both c-Jun and ATF3 are upregulated in neurons in response to axotomy.

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Activating Transcription Factor 3 Animals Blotting, Western Cell Count Cell Line, Tumor Immunohistochemistry Mice Neurites Neurons Precipitin Tests Proto-Oncogene Proteins c-jun Rats Transcription Factors Transfection Tubulin Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Andree G Pearson, Carol W Gray, John F Pearson, Jeffrey M Greenwood, Matthew J During, Michael Dragunow. 2003-12-12. ATF3 enhances c-Jun-mediated neurite sprouting.. https://doi.org/10.1016/j.molbrainres.2003.09.014

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