Frataxin gene (FXN) expression is reduced in Friedreich's ataxia patients due to an increase in the number of GAA trinucleotides in intron 1. The frataxin protein, encoded by that gene, plays an important role in mitochondria's iron metabolism. Platinum TALE (plTALE) proteins targeting the regulatory region of the FXN gene, fused with a transcriptional activator (TA) such as VP64 or P300, were used to increase the expression of that gene. Many effectors, plTALE, plTALE, and plTALE, targeting 14 sequences of the FXN gene promoter or intron 1 were produced. This permitted selection of 3 plTALE and 2 plTALE that increased FXN gene expression by up to 19-fold in different Friedreich ataxia (FRDA) primary fibroblasts. Adeno-associated viruses were used to deliver the best effectors to the YG8R mouse model to validate their efficiencies in vivo. Our results showed that these selected plTALE or plTALE induced transcriptional activity of the endogenous FXN gene as well as expression of the frataxin protein in YG8R mouse heart by 10-fold and in skeletal muscles by up to 35-fold. The aconitase activity was positively modulated by the frataxin level in mitochondria, and it was, thus, increased in vitro and in vivo by the increased frataxin expression.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6019861 | PMC |
| http://dx.doi.org/10.1016/j.omtn.2018.04.009 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Design and validation of cell-based potency assays for frataxin supplementation treatments.
Mol Ther Methods Clin Dev
December 2024
Department of Neurology, O'Donnell Brain Institute, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
Friedreich's ataxia (FRDA) is a multisystem, autosomal recessive disorder caused by mutations in the frataxin () gene. As FRDA is considered an FXN deficiency disorder, numerous therapeutic approaches in development or clinical trials aim to supplement FXN or restore endogenous expression. These include gene therapy, protein supplementation, genome editing or upregulation of transcription.
View Article and Find Full Text PDFFriedreich Ataxia: An (Almost) 30-Year History After Gene Discovery.
Neurol Genet
February 2025
Department of Neurology and Neurosurgery, McGill University, Montreal, Canada.
In the late 1800s, Nikolaus Friedreich first described "degenerative atrophy of the posterior columns of the spinal cord," noting its connection to progressive ataxia, sensory loss, and muscle weakness, now recognized as Friedreich ataxia (FRDA). Renewed interest in the disease in the 1970s and 80s by the Quebec Cooperative Group and by Anita Harding led to the development of clinical diagnostic criteria and insights into associated biochemical abnormalities, although the primary defect remained unknown. In 1988, Susan Chamberlain mapped FRDA's location on chromosome 9.
View Article and Find Full Text PDFFriedreich ataxia: what can we learn from non-GAA repeat mutations?
Neurodegener Dis Manag
January 2025
Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA.
Friedreich ataxia (FRDA) is a slowly progressive neurological disease resulting from decreased levels of the protein frataxin, a small mitochondrial protein that facilitates the synthesis of iron-sulfur clusters in the mitochondrion. It is caused by GAA (guanine-adenine-adenine) repeat expansions in the gene in 96% of patients, with 4% of patients carrying other mutations (missense, nonsense, deletion) in the gene. Compound heterozygote patients with one expanded GAA allele and a non-GAA repeat mutation can have subtle differences in phenotype from typical FRDA, including, in patients with selected missense mutations, both more severe features and less severe features in the same patient.
View Article and Find Full Text PDFSafety and efficacy of omaveloxolone v/s placebo for the treatment of Friedreich's ataxia in patients aged more than 16 years: a systematic review.
Orphanet J Rare Dis
December 2024
Discovery Research Division, Indian Council of Medical Research (ICMR) Headquarters, V. Ramalingaswami Bhawan, Ansari Nagar, P.O. Box 4911, New Delhi, 110029, India.
Background: Friedreich's ataxia (FA) is a rare genetic disorder caused by silencing of the frataxin gene (FXN), which leads to multiorgan damage. Nrf2 is a regulator of FXN, which is a modulator of oxidative stress in animals and humans. Omaveloxolone (Omav) is an Nrf2 activator and has been reported to have antioxidative potential in various disease conditions.
View Article and Find Full Text PDFis essential for zebrafish embryogenesis and pronephros formation.
Front Cell Dev Biol
December 2024
Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.
Background And Objectives: Friedreich's Ataxia (FRDA) is a genetic disease that affects a variety of different tissues. The disease is caused by a mutation in the gene ( which is important for the synthesis of iron-sulfur clusters. The primary pathologies of FRDA are loss of motor control and cardiomyopathy.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!