A Requirement for Mena, an Actin Regulator, in Local mRNA Translation in Developing Neurons

Neuron. 2017 Aug 2;95(3):608-622.e5. doi: 10.1016/j.neuron.2017.06.048. Epub 2017 Jul 20.

Abstract

During neuronal development, local mRNA translation is required for axon guidance and synaptogenesis, and dysregulation of this process contributes to multiple neurodevelopmental and cognitive disorders. However, regulation of local protein synthesis in developing axons remains poorly understood. Here, we uncover a novel role for the actin-regulatory protein Mena in the formation of a ribonucleoprotein complex that involves the RNA-binding proteins HnrnpK and PCBP1 and regulates local translation of specific mRNAs in developing axons. We find that translation of dyrk1a, a Down syndrome- and autism spectrum disorders-related gene, is dependent on Mena, both in steady-state conditions and upon BDNF stimulation. We identify hundreds of additional mRNAs that associate with the Mena complex, suggesting that it plays broader role(s) in post-transcriptional gene regulation. Our work establishes a dual role for Mena in neurons, providing a potential link between regulation of actin dynamics and local translation.

Keywords: Dyrk1a; ENAH; Ena/VASP; Mena; axon guidance; developing axon; growth cone; local translation; ribonucleoprotein.

MeSH terms

  • Actins / metabolism*
  • Animals
  • Axons / physiology*
  • Cell Movement / physiology
  • Cytoskeletal Proteins / metabolism
  • Gene Expression Regulation / physiology
  • Neurogenesis / physiology*
  • Neurons / metabolism*
  • Protein Biosynthesis
  • RNA, Messenger / metabolism*

Substances

  • Actins
  • Cytoskeletal Proteins
  • RNA, Messenger