Article

Phosphorylation of the Brn-3a transcription factor is modulated during differentiation and regulates its functional activity.

MMBU, Institute of Child Health, 30 Guilford Street, WC1N 1EH London, UK.
Molecular Brain Research (Impact Factor: 2). 12/2005; 141(1):10-8. DOI: 10.1016/j.molbrainres.2005.07.013
Source: PubMed

ABSTRACT Brn-3a is a transcription factor expressed in a subset of neurons of the peripheral nervous system. Its role encompasses the activation of genes involved in neuronal differentiation and survival. While a lot of data have been produced on Brn-3a target promoters, very little is known about the upstream regulatory signals that mediate its activation in response to differentiation. In this work, we describe for the first time that Brn-3a is phosphorylated in IMR-32 neuroblastoma cells in response to differentiation induced by retinoic acid treatment and that its post-translational modification is potentially mediated by the activation of the MAPK/ERK pathway. Furthermore, we show that the mutation of a putative phosphorylated amino acid strongly reduces the ability of Brn-3a to mediate the differentiation of IMR-32 cells.

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