Work

GGGGCC microsatellite RNA is neuritically localized, induces branching defects, and perturbs transport granule function

Year: 2015

Type: article

Abstract: Microsatellite expansions are the leading cause of numerous neurodegenerative disorders. Here we demonstrate that GGGGCC and CAG microsatellite repeat RNAs associated with C9orf72 in amyotrophic lateral sclerosis/frontotemporal dementia and with polyglutamine diseases, respectively, localize to neuritic granules that undergo active transport into distal neuritic segments. In cultured mammalian spinal cord neurons, the presence of neuritic GGGGCC repeat RNA correlates with neuronal branching defects, and the repeat RNA localizes to granules that label with fragile X mental retardation protein (FMRP), a transport granule component. Using a Drosophila GGGGCC expansion disease model, we characterize dendritic branching defects that are modulated by FMRP and Orb2. The human orthologs of these modifiers are misregulated in induced pluripotent stem cell-differentiated neurons (iPSNs) from GGGGCC expansion carriers. These data suggest that expanded repeat RNAs interact with the messenger RNA transport and translation machinery, causing transport granule dysfunction. This could be a novel mechanism contributing to the neuronal defects associated with C9orf72 and other microsatellite expansion diseases.

Source: eLife

DOI: 10.7554/elife.08881

Authors: Alondra Schweizer Burguete, Sandra Almeida, Fen-Biao Gao, Robert Kalb, Michael R Akins, Nancy M Bonini

Institutions: University of Pennsylvania, University of Massachusetts Chan Medical School, Children's Hospital of Philadelphia, Drexel University

Language: English

Topic: Amyotrophic Lateral Sclerosis Research

Subfield: Neurology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,500