Transactivation capacity of Pea3 transcription factor on promoter of NeuroD1

Pea3, a member of the ETS (E26 transcription-specific) family of transcription factor is a nuclear phosphoprotein and has been shown to be involved in developmental processes with its expression during embryonic stages, in cancer metastatis by regulating the transcription of matrix metalloproteases or in branching morphogenesis of several organs like lung or mammary glands. In addition to this organ branching, Pea3 is involved in the axonal arborization. It has been shown that Pea3 expression is important for connection of the motor axons to the target muscles. Pea3 presence in branching and axonal projection processes led us to study the genes which can be regulated by Pea3. Among many of its potential target genes we are particularly interested in the novel target NeuroD for its role in differentiation of newborn neurons where they might be involved in the differentiation and allowing axon growth. In this study we identify the regions on promoter of NeuroD where Pea3 binds and regulates its expression in addition to this we also show how Pea3 phosphorylation on specific Serine /Proline residues by MAP kinase pathways affects its transactivating capacity for the expression of NeuroD. The data from this study may give us insight about how and with which target genes Pea3 is involved in the development of a neuron.