Aminoacyl-tRNA synthetases (aARS) are enzymes that play a crucial role in protein translation. They are responsible for attaching an amino acid to a transfer RNA, or tRNA, which carries the amino acid to the ribosome for incorporation into a growing polypeptide chain, or protein.
For almost every amino acid (there are 20), there are unique aARS enzymes. Separate aARS enzymes exist for cytosolic (cellular) translation, and mitochondrial translation. Cytosolic aARS are names ARS1. Mitochondrial aARS are named ARS2. The first letter of the enzyme refers to the amino acid the enzyme is unique to. For example, IARS1 is the name of the cytosolic isoleucine aARS enzyme, which is responsible for attaching the amino acid isoleucine to isoleucine-specific tRNA.
Mutations in multiple aARS genes are associated with various symptoms. Overall, autosomal dominant mutations cause Charcot-Marie-Tooth neuropathies and white matter disease, while autosomal recessive mutations cause a multi-organ phenotype, including dysmaturity and failure to thrive, developmental delay, anemia, pulmonary failure, liver failure, and more. New disease causing mutations in these genes are frequently discovered. We frequently update the list of literature covering all case reports.