Fragile X mental retardation protein (FMRP) controls diacylglycerol kinase activity in neurons

Ricardos Tabet, Enora Moutin, Jérôme A J Becker, Dimitri Heintz, Laetitia Fouillen, Eric Flatter, Wojciech Krȩzel, Violaine Alunni, Pascale Koebel, Doulaye Dembélé, Flora Tassone, Barbara Bardoni, Jean Louis Mandel, Nicolas Vitale, Dominique Muller, Julie Le Merrer, Hervé Moine

Research output: Contribution to journalArticle

47 Scopus citations

Abstract

Fragile X syndrome (FXS) is caused by the absence of the Fragile X Mental Retardation Protein (FMRP) in neurons. In the mouse, the lack of FMRP is associated with an excessive translation of hundreds of neuronal proteins, notably including postsynaptic proteins. This local protein synthesis deregulation is proposed to underlie the observed defects of glutamatergic synapse maturation and function and to affect preferentially the hundreds of mRNA species that were reported to bind to FMRP. How FMRP impacts synaptic protein translation and which mRNAs are most important for the pathology remain unclear. Here we show by cross-linking immunoprecipitation in cortical neurons that FMRP is mostly associated with one unique mRNA: diacylglycerol kinase kappa (Dgkκ), a master regulator that controls the switch between diacylglycerol and phosphatidic acid signaling pathways. The absence of FMRP in neurons abolishes group 1 metabotropic glutamate receptor-dependent DGK activity combined with a loss of Dgkκ expression. The reduction of Dgkκ in neurons is sufficient to cause dendritic spine abnormalities, synaptic plasticity alterations, and behavior disorders similar to those observed in the FXS mouse model. Overexpression of Dgkκ in neurons is able to rescue the dendritic spine defects of the Fragile X Mental Retardation 1 gene KO neurons. Together, these data suggest that Dgkκ deregulation contributes to FXS pathology and support a model where FMRP, by controlling the translation of Dgkκ, indirectly controls synaptic proteins translation and membrane properties by impacting lipid signaling in dendritic spine.

Original languageEnglish (US)
Pages (from-to)E3619-E3628
JournalProceedings of the National Academy of Sciences of the United States of America
Volume113
Issue number26
DOIs
StatePublished - Jun 28 2016

Keywords

  • CLIP
  • Diacylglycerol kinase
  • FMRP
  • Fragile X syndrome
  • Translation control

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Fragile X mental retardation protein (FMRP) controls diacylglycerol kinase activity in neurons'. Together they form a unique fingerprint.

  • Cite this

    Tabet, R., Moutin, E., Becker, J. A. J., Heintz, D., Fouillen, L., Flatter, E., Krȩzel, W., Alunni, V., Koebel, P., Dembélé, D., Tassone, F., Bardoni, B., Mandel, J. L., Vitale, N., Muller, D., Merrer, J. L., & Moine, H. (2016). Fragile X mental retardation protein (FMRP) controls diacylglycerol kinase activity in neurons. Proceedings of the National Academy of Sciences of the United States of America, 113(26), E3619-E3628. https://doi.org/10.1073/pnas.1522631113