Bifunctional glutamate/proline--tRNA ligase, also called bifunctional aminoacyl-tRNA synthetase, is an enzyme that in humans is encoded by the EPRS1 gene (previously EPRS). This enzyme is located in the cytoplasm, where it attaches the amino acids glutamate and proline to their corresponding transfer RNA (tRNAGlu and tRNAPro) as part of RNA-to-protein translation.
Alternative splicing has been observed for this gene, but the full-length nature and biological validity of the variant have not been determined.
Aminoacyl-tRNA synthetases are a class of enzymes that charge tRNAs with their cognate amino acids. The protein encoded by this gene is a multifunctional aminoacyl-tRNA synthetase that catalyzes the aminoacylation of glutamic acid and proline tRNA species.
Phosphorylation of EPRS is reported to be essential for the formation of GAIT (Gamma-interferon Activated Inhibitor of Translation) complex that regulates the translation of multiple genes in monocytes and macrophages.
EPRS1 acts, in human cells, as a proviral factor in mammarenaviruses infection, including LCMV, JUNV, and LASV, and its inhibition using halofuginon compound, a prolyl domain inhibitor, completely abolishes the viral infection by interrupting viral assembly and budding.
EPRS has been shown to interact with POU2F1, Heat shock protein 90kDa alpha (cytosolic), member A1 and IARS.
Pathogenic mutations in EPRS1 are associated with a type of disorder of the neural white matter (Leukodystrophy) which is called hypomyelinating leukodystrophy-15 (HLD15).