Recurrent De Novo and Biallelic Variation of ATAD3A, Encoding a Mitochondrial Membrane Protein, Results in Distinct Neurological Syndromes.
Am J Hum Genet
; 99(4): 831-845, 2016 Oct 06.
Article
en En
| MEDLINE
| ID: mdl-27640307
ABSTRACT
ATPase family AAA-domain containing protein 3A (ATAD3A) is a nuclear-encoded mitochondrial membrane protein implicated in mitochondrial dynamics, nucleoid organization, protein translation, cell growth, and cholesterol metabolism. We identified a recurrent de novo ATAD3A c.1582C>T (p.Arg528Trp) variant by whole-exome sequencing (WES) in five unrelated individuals with a core phenotype of global developmental delay, hypotonia, optic atrophy, axonal neuropathy, and hypertrophic cardiomyopathy. We also describe two families with biallelic variants in ATAD3A, including a homozygous variant in two siblings, and biallelic ATAD3A deletions mediated by nonallelic homologous recombination (NAHR) between ATAD3A and gene family members ATAD3B and ATAD3C. Tissue-specific overexpression of borR534W, the Drosophila mutation homologous to the human c.1582C>T (p.Arg528Trp) variant, resulted in a dramatic decrease in mitochondrial content, aberrant mitochondrial morphology, and increased autophagy. Homozygous null bor larvae showed a significant decrease of mitochondria, while overexpression of borWT resulted in larger, elongated mitochondria. Finally, fibroblasts of an affected individual exhibited increased mitophagy. We conclude that the p.Arg528Trp variant functions through a dominant-negative mechanism that results in small mitochondria that trigger mitophagy, resulting in a reduction in mitochondrial content. ATAD3A variation represents an additional link between mitochondrial dynamics and recognizable neurological syndromes, as seen with MFN2, OPA1, DNM1L, and STAT2 mutations.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Adenosina Trifosfatasas
/
Proteínas Mitocondriales
/
Alelos
/
Proteínas de la Membrana
/
Mitocondrias
/
Mutación
/
Enfermedades del Sistema Nervioso
Límite:
Adult
/
Animals
/
Child
/
Child, preschool
/
Female
/
Humans
/
Infant
/
Male
/
Newborn
Idioma:
En
Revista:
Am J Hum Genet
Año:
2016
Tipo del documento:
Article