PUBLICATION
Clinical, neuroradiological and molecular characterization of mitochondrial threonyl-tRNA-synthetase (TARS2)-related disorder
- Authors
- Accogli, A., Lin, S.J., Severino, M., Kim, S.H., Huang, K., Rocca, C., Landsverk, M., Zaki, M., Al-Maawali, A., Srinivasan, V.M., Al-Thihli, K., Schaefer, G.B., Davis, M., Tonduti, D., Doneda, C., Marten, L.M., Mühlhausen, C., Gomez, M., Lamantea, E., Mena, R., Nizon, M., Procaccio, V., Begtrup, A., Telegrafi, A., Cui, H., Schulz, H.L., Mohr, J., Biskup, S., Loos, M.A., Aráoz, H.V., Salpietro, V., Keppen, L.D., Chitre, M., Petree, C., Raymond, L., Vogt, J., Swayer, L.B., Basinger, A.A., Pedersen, S.V., Pearson, T.S., Grange, D.K., Lingapp, L., McDunnah, P., Horvath, R., Cogne, B., Isidor, B., Hahn, A., Gripp, K., Jafarnejad, S.M., Ostergaard, E., Prada, C.E., Ghezzi, D., Gowda, V.K., Taylor, R.W., Sonenberg, N., Houlden, H., Sissler, M., Varshney, G.K., Maroofian, R.
- ID
- ZDB-PUB-230716-47
- Date
- 2023
- Source
- Genetics in medicine : official journal of the American College of Medical Genetics 25(11): 100938 (Journal)
- Registered Authors
- Horvath, Rita, Lin, Sheng-Jia, Varshney, Gaurav
- Keywords
- TARS2, cerebellar atrophy, mTORC1 signaling, mitochondrial dysfunction, mitochondrial threonyl-tRNA-synthetase, white matter
- MeSH Terms
-
- RNA, Transfer*
- Mutation
- Humans
- Phenotype
- Animals
- PubMed
- 37454282 Full text @ Genet. Med.
Abstract
Purpose Biallelic variants in TARS2, encoding the mitochondrial threonyl-tRNA-synthetase, have been reported in a small group of individuals displaying a neurodevelopmental phenotype, but with limited neuroradiological data and insufficient evidence for causality of the variants.
Methods Exome or genome sequencing was carried out in 15 families. Clinical and neuroradiological evaluation was performed for all affected individuals, including review of 10 previously reported individuals. The pathogenicity of TARS2 variants was evaluated using in vitro assays, and a zebrafish model.
Results We report 18 new individuals harboring biallelic TARS2 variants. Phenotypically, these individuals show developmental delay/intellectual disability, regression, cerebellar and cerebral atrophy, basal ganglia signal alterations, hypotonia, cerebellar signs and increased blood lactate. In vitro studies showed that variants within the TARS2301-381 region had decreased binding to Rag GTPases, likely impairing mTORC1 activity. The zebrafish model recapitulated key features of the human phenotype and unraveled dysregulation of downstream targets of mTORC1 signaling. Functional testing of the variants confirmed the pathogenicity in a zebrafish model.
Conclusion We define the clinico-radiological spectrum of TARS2-related mitochondrial disease, unveil the likely involvement of the mTORC1 signaling pathway as a distinct molecular mechanism, and establish a TARS2 zebrafish model as an important tool to study variant pathogenicity.
Genes / Markers
Figure Gallery (5 images)
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping