Sam68 promotes self-renewal and glycolytic metabolism in mouse neural progenitor cells by modulating Aldh1a3 pre-mRNA 3'-end processing

  1. Piergiorgio La Rosa
  2. Pamela Bielli
  3. Claudia Compagnucci
  4. Eleonora Cesari
  5. Elisabetta Volpe
  6. Stefano Farioli Vecchioli
  7. Claudio Sette  Is a corresponding author
  1. University of Rome Tor Vergata, Italy
  2. Fondazione Santa Lucia, Italy
  3. Institute of Cell Biology and Neurobiology CNR, Italy

Abstract

The balance between self-renewal and differentiation of neural progenitor cells (NPCs) dictates neurogenesis and proper brain development. We found that the RNA binding protein Sam68 is strongly expressed in neurogenic areas of the neocortex and supports the self-renewing potential of mouse NPCs. Knockout of Sam68 constricted the pool of proliferating NPCs by accelerating their cell cycle exit and differentiation into post-mitotic neurons. Sam68 function was linked to regulation of Aldh1a3 pre-mRNA 3'-end processing. Binding of Sam68 to an intronic polyadenylation site prevents its recognition and premature transcript termination, favouring expression of a functional enzyme. The lower ALDH1A3 expression and activity in Sam68-/- NPCs results in reduced glycolysis and clonogenicity, thus depleting the embryonic NPC pool and limiting cortical expansion. Our study identifies Sam68 as a key regulator of NPC self-renewal and establishes a novel link between modulation of ALDH1A3 expression and maintenance of high glycolytic metabolism in the developing cortex.

Article and author information

Author details

  1. Piergiorgio La Rosa

    Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  2. Pamela Bielli

    Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  3. Claudia Compagnucci

    Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  4. Eleonora Cesari

    Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  5. Elisabetta Volpe

    Neuroimmunology, Fondazione Santa Lucia, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  6. Stefano Farioli Vecchioli

    Institute of Cell Biology and Neurobiology CNR, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  7. Claudio Sette

    Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
    For correspondence
    claudio.sette@uniroma2.it
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2864-8266

Funding

Telethon (GGP14095)

  • Claudio Sette

Associazione Italiana Ricerca sul Cancro (IG14581)

  • Claudio Sette

Muscular Dystrophy Association

  • Claudio Sette

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Marianne Bronner, California Institute of Technology, United States

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the Italian Ministry of Health. All of the animals were handled according to approved institutional animal care and use committee of the University ofRome Tor Vergata. The protocol was approved by the Committee on the Ethics of Animal Experiments of the University of Rome Tor Vergata. Every effort was made to minimize suffering of mice.

Version history

  1. Received: August 17, 2016
  2. Accepted: November 14, 2016
  3. Accepted Manuscript published: November 15, 2016 (version 1)
  4. Version of Record published: November 24, 2016 (version 2)

Copyright

© 2016, La Rosa et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 1,963
    views
  • 404
    downloads
  • 51
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Piergiorgio La Rosa
  2. Pamela Bielli
  3. Claudia Compagnucci
  4. Eleonora Cesari
  5. Elisabetta Volpe
  6. Stefano Farioli Vecchioli
  7. Claudio Sette
(2016)
Sam68 promotes self-renewal and glycolytic metabolism in mouse neural progenitor cells by modulating Aldh1a3 pre-mRNA 3'-end processing
eLife 5:e20750.
https://doi.org/10.7554/eLife.20750

Share this article

https://doi.org/10.7554/eLife.20750

Further reading

    1. Cancer Biology
    2. Cell Biology
    Ian Lorimer
    Insight

    Establishing a zebrafish model of a deadly type of brain tumor highlights the role of the immune system in the early stages of the disease.

    1. Cell Biology
    2. Neuroscience
    Jaebin Kim, Edwin Bustamante ... Scott H Soderling
    Research Article

    One of the most extensively studied members of the Ras superfamily of small GTPases, Rac1 is an intracellular signal transducer that remodels actin and phosphorylation signaling networks. Previous studies have shown that Rac1-mediated signaling is associated with hippocampal-dependent working memory and longer-term forms of learning and memory and that Rac1 can modulate forms of both pre- and postsynaptic plasticity. How these different cognitive functions and forms of plasticity mediated by Rac1 are linked, however, is unclear. Here, we show that spatial working memory in mice is selectively impaired following the expression of a genetically encoded Rac1 inhibitor at presynaptic terminals, while longer-term cognitive processes are affected by Rac1 inhibition at postsynaptic sites. To investigate the regulatory mechanisms of this presynaptic process, we leveraged new advances in mass spectrometry to identify the proteomic and post-translational landscape of presynaptic Rac1 signaling. We identified serine/threonine kinases and phosphorylated cytoskeletal signaling and synaptic vesicle proteins enriched with active Rac1. The phosphorylated sites in these proteins are at positions likely to have regulatory effects on synaptic vesicles. Consistent with this, we also report changes in the distribution and morphology of synaptic vesicles and in postsynaptic ultrastructure following presynaptic Rac1 inhibition. Overall, this study reveals a previously unrecognized presynaptic role of Rac1 signaling in cognitive processes and provides insights into its potential regulatory mechanisms.