Samia L Pratt, Mariana Zarate-Mendez, Lidiia Koludarova, Sonja Jansson, Mikko Airavaara, Irena Hlushchuk, David Coleman, Caleb Heffner, Rita Horvath, Brendan J Battersby, Robert W Burgess
{"title":"Evaluating the feasibility of gene replacement strategies to treat MTRFR deficiency.","authors":"Samia L Pratt, Mariana Zarate-Mendez, Lidiia Koludarova, Sonja Jansson, Mikko Airavaara, Irena Hlushchuk, David Coleman, Caleb Heffner, Rita Horvath, Brendan J Battersby, Robert W Burgess","doi":"10.1242/dmm.052120","DOIUrl":null,"url":null,"abstract":"<p><p>Mitochondrial translation release factor in rescue (MTRFR) catalyzes a termination step in protein synthesis, facilitating release of the nascent chain from mitoribosomes. Pathogenic variants in MTRFR cause MTRFR deficiency and are loss-of-function variants. Here, we tested gene replacement as a possible therapeutic strategy. A truncating mutation (K155*) was generated in mice; however, homozygotes die embryonically whereas mice heterozygous for this K155* allele are normal. We also generated transgenic strains expressing either wild-type human MTRFR or a partially functional MTRFR. Despite dose-dependent phenotypes from overexpression in vitro, neither transgene caused adverse effects in vivo. In K155* homozygous mice, the wild-type MTRFR transgene completely rescued the phenotype with only one copy present, whereas the mutant transgene rescued less efficiently. Detailed evaluation of mice rescued with the wild-type MTRFR transgene revealed no abnormalities. In human induced pluripotent stem cell (hiPSC)-derived knockdown neurons, mitochondrial phenotypes were corrected by AAV9-mediated delivery of MTRFR. Thus, we find no toxicity from truncated gene products or overexpression of MTRFR in vivo, and expression of MTRFR corrects phenotypes in both mouse and hiPSC models.</p>","PeriodicalId":11144,"journal":{"name":"Disease Models & Mechanisms","volume":"18 5","pages":""},"PeriodicalIF":3.3000,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12171093/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Disease Models & Mechanisms","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1242/dmm.052120","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/6/2 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Mitochondrial translation release factor in rescue (MTRFR) catalyzes a termination step in protein synthesis, facilitating release of the nascent chain from mitoribosomes. Pathogenic variants in MTRFR cause MTRFR deficiency and are loss-of-function variants. Here, we tested gene replacement as a possible therapeutic strategy. A truncating mutation (K155*) was generated in mice; however, homozygotes die embryonically whereas mice heterozygous for this K155* allele are normal. We also generated transgenic strains expressing either wild-type human MTRFR or a partially functional MTRFR. Despite dose-dependent phenotypes from overexpression in vitro, neither transgene caused adverse effects in vivo. In K155* homozygous mice, the wild-type MTRFR transgene completely rescued the phenotype with only one copy present, whereas the mutant transgene rescued less efficiently. Detailed evaluation of mice rescued with the wild-type MTRFR transgene revealed no abnormalities. In human induced pluripotent stem cell (hiPSC)-derived knockdown neurons, mitochondrial phenotypes were corrected by AAV9-mediated delivery of MTRFR. Thus, we find no toxicity from truncated gene products or overexpression of MTRFR in vivo, and expression of MTRFR corrects phenotypes in both mouse and hiPSC models.
期刊介绍:
Disease Models & Mechanisms (DMM) is an online Open Access journal focusing on the use of model systems to better understand, diagnose and treat human disease.