Nuclear Localization of Huntingtin mRNA Is Specific to Cells of Neuronal Origin
Marie-Cécile Didiot,
Chantal M. Ferguson,
Socheata Ly,
Andrew H. Coles,
Abigail O. Smith,
Alicia A. Bicknell,
Lauren M. Hall,
Ellen Sapp,
Dimas Echeverria,
Athma A. Pai,
Marian DiFiglia,
Melissa J. Moore,
Lawrence J. Hayward,
Neil Aronin,
Anastasia Khvorova
Affiliations
Marie-Cécile Didiot
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Corresponding author
Chantal M. Ferguson
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Socheata Ly
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Andrew H. Coles
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Abigail O. Smith
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Alicia A. Bicknell
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Lauren M. Hall
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Ellen Sapp
MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA 02129, USA
Dimas Echeverria
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Athma A. Pai
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Marian DiFiglia
MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA 02129, USA
Melissa J. Moore
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
Lawrence J. Hayward
Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605, USA
Neil Aronin
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
Anastasia Khvorova
RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA; Corresponding author
Summary: Huntington’s disease (HD) is a monogenic neurodegenerative disorder representing an ideal candidate for gene silencing with oligonucleotide therapeutics (i.e., antisense oligonucleotides [ASOs] and small interfering RNAs [siRNAs]). Using an ultra-sensitive branched fluorescence in situ hybridization (FISH) method, we show that ∼50% of wild-type HTT mRNA localizes to the nucleus and that its nuclear localization is observed only in neuronal cells. In mouse brain sections, we detect Htt mRNA predominantly in neurons, with a wide range of Htt foci observed per cell. We further show that siRNAs and ASOs efficiently eliminate cytoplasmic HTT mRNA and HTT protein, but only ASOs induce a partial but significant reduction of nuclear HTT mRNA. We speculate that, like other mRNAs, HTT mRNA subcellular localization might play a role in important neuronal regulatory mechanisms. : Huntington’s disease (HD) is a monogenic neurodegenerative disorder representing an ideal candidate for gene silencing with oligonucleotide therapeutics. Didiot et al. examine the subcellular localization of HTT mRNA in non-neuronal and neuronal cells and the efficiency of oligonucleotide therapeutics on HTT mRNA subcellular fractions. Keywords: Huntington’s disease, HTT mRNA, CAG repeat RNA foci, RNA fluorescence in situ hybridization, confocal microscopy, siRNAs, ASOs