EURON and THEME joint PhD meeting
EURON and THEME joint PhD meeting
EURON and THEME joint PhD meeting
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71<br />
<strong>EURON</strong> <strong>and</strong> <strong>THEME</strong> <strong>joint</strong> <strong>meeting</strong> 2011<br />
Identification of microRNAs regulating neuronal<br />
differentiation of human neural stem cells<br />
Laura Mürtz 1 , Lodovica Borghese 1 , Beate Roese-Koerner 1 , S<strong>and</strong>ra Weinhold 2 ,<br />
Philipp Koch 1 , Peter Wernet 2 , Markus Uhrberg 2 <strong>and</strong> Oliver Brüstle 1<br />
1 Institute of Reconstructive Neurobiology, Life <strong>and</strong> Brain Center, University of Bonn; 2 Institute for Transplantation<br />
Diagnostics <strong>and</strong> Cell Therapeutics, Heinrich-Heine University Düsseldorf.<br />
MicroRNAs are a class of small non-coding RNAs that act as post-transcriptional<br />
regulators of gene expression. Studies in model organisms have demonstrated<br />
critical roles for a number of microRNAs in neuronal development, but their<br />
specific functions have not been fully examined. Likewise, data on microRNA<br />
function in the context of human neural development <strong>and</strong> neural stem cell<br />
biology is particularly scarce. Our human embryonic stem cell (hESC) based<br />
neural differentiation paradigm provides a useful model for the analysis of<br />
microRNA profiles in human pluripotent <strong>and</strong> multipotent stem cells <strong>and</strong> for the<br />
identification <strong>and</strong> functional characterization of novel microRNAs associated<br />
with neuronal differentiation. We assessed microRNA of human ES cells (hES,<br />
I3 line), of long-term self-renewing neuroepithelial-like stem cells (lt-NES® cells)<br />
(Koch et al. 2009) <strong>and</strong> of 15- <strong>and</strong> 30-days old differentiated neuronal cultures<br />
(ND15, ND30) using a quantitative real-time PCR multiplex assay. We validated<br />
the identified expression patterns for several microRNAs by Northern blot<br />
analysis in two independent hES cell lines (I3 <strong>and</strong> H9.2) indicating the reliability<br />
of our approach. Furthermore we were able to confirm previous assignments of<br />
ES cell-specific <strong>and</strong> brain-specific microRNAs. In addition, we identified several<br />
novel microRNAs, besides the known neuronal microRNAs, i.e. miR-124 <strong>and</strong><br />
miR-125, as up-regulated during human neural stem cell differentiation. Stable<br />
overexpression of the newly identified microRNAs, just like the overexpression of<br />
miR-124 <strong>and</strong> miR-125, resulted in an increased rate of neuronal differentiation. Our<br />
data demonstrate that these microRNAs are not only markers of differentiation<br />
but may also function as regulators of human neuronal differentiation.