학술논문

Gain of Toxicity from ALS/FTD-Linked Repeat Expansions in C9ORF72 Is Alleviated by Antisense Oligonucleotides Targeting GGGGCC-Containing RNAs
Document Type
article
Source
Neuron. 90(3)
Subject
Biological Psychology
Biomedical and Clinical Sciences
Neurosciences
Psychology
Brain Disorders
Genetics
Dementia
Neurodegenerative
Acquired Cognitive Impairment
Behavioral and Social Science
ALS
Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD)
Frontotemporal Dementia (FTD)
Rare Diseases
Aetiology
2.1 Biological and endogenous factors
Neurological
Amyotrophic Lateral Sclerosis
Animals
C9orf72 Protein
DNA Repeat Expansion
Frontotemporal Dementia
Guanine Nucleotide Exchange Factors
Mice
Transgenic
Neurons
Oligonucleotides
Antisense
RNA
Cognitive Sciences
Neurology & Neurosurgery
Biological psychology
Language
Abstract
Hexanucleotide expansions in C9ORF72 are the most frequent genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Disease mechanisms were evaluated in mice expressing C9ORF72 RNAs with up to 450 GGGGCC repeats or with one or both C9orf72 alleles inactivated. Chronic 50% reduction of C9ORF72 did not provoke disease, while its absence produced splenomegaly, enlarged lymph nodes, and mild social interaction deficits, but not motor dysfunction. Hexanucleotide expansions caused age-, repeat-length-, and expression-level-dependent accumulation of RNA foci and dipeptide-repeat proteins synthesized by AUG-independent translation, accompanied by loss of hippocampal neurons, increased anxiety, and impaired cognitive function. Single-dose injection of antisense oligonucleotides (ASOs) that target repeat-containing RNAs but preserve levels of mRNAs encoding C9ORF72 produced sustained reductions in RNA foci and dipeptide-repeat proteins, and ameliorated behavioral deficits. These efforts identify gain of toxicity as a central disease mechanism caused by repeat-expanded C9ORF72 and establish the feasibility of ASO-mediated therapy.