[Neuronal Plasticity-related Mechanisms Triggered by the Transcriptional Coactivator MRTFB, a Regulator for Neuronal...

Synaptic plasticity is a key mechanism underlying long-term memory and learning, with proposed associations with altered actin cytoskeleton and gene expression in neurons. Myocardin-related transcription factor (MRTF) family members, abundantly expressed in the brain, have actin-binding motifs at the N-terminus and act as cofactors of serum response factor (SRF). Rho signaling may promote MRTF's release from G-actin and subsequent translocation into the nucleus, and increases SRF-dependent gene expression. MRTF is therefore thought to act as a link between morphological change and gene expression in neurons. In this review, we focus on the neurotrophin, brain-derived neurotrophic factor (BDNF). BDNF plays crucial roles in neuronal survival, gene expression, and dendritic growth, which are essential for neuronal plasticity. As previous studies suggest that BDNF triggers the activation of MRTF/SRF-mediated signal transduction, we have studied how this supposed regulatory ligand is involved in the functional MRTF changes in neurons. We review the BDNF-mediated roles of MRTF in neuronal morphology and gene expression and briefly discuss the possible involvement of MRTF in neurodevelopmental disorders, such as autism spectrum disorder and intellectual disability.