FEATURES

FAMILY

class-II aminoacyl-tRNA synthetase family

DESCRIPTION

Also known as SYK_HUMAN, KARS1, KARS, KIAA0070. Catalyzes the specific attachment of an amino acid to its cognate tRNA in a 2 step reaction: the amino acid (AA) is first activated by ATP to form AA-AMP and then transferred to the acceptor end of the tRNA (PubMed:9278442, PubMed:18029264, PubMed:18272479). When secreted, acts as a signaling molecule that induces immune response through the activation of monocyte/macrophages (PubMed:15851690). Catalyzes the synthesis of the signaling molecule diadenosine tetraphosphate (Ap4A), and thereby mediates disruption of the complex between HINT1 and MITF and the concomitant activation of MITF transcriptional activity (PubMed:5338216, PubMed:14975237, PubMed:19524539, PubMed:23159739)., (Microbial infection) Interacts with HIV-1 virus GAG protein, facilitating the selective packaging of tRNA(3)(Lys), the primer for reverse transcription initiation. Homodimer and tetradimer (PubMed:18272479, PubMed:23159739, PubMed:26074468, PubMed:28887846). Part of the multisynthetase complex (MSC), a multisubunit complex that groups tRNA ligases for Arg (RARS), Asp (DARS), Gln (QARS), Ile (IARS), Leu (LARS), Lys (KARS), Met (MARS) the bifunctional ligase for Glu and Pro (EPRS) and the auxiliary subunits AIMP1/p43, AIMP2/p38 and EEF1E1/p18 (PubMed:19131329, PubMed:19289464, PubMed:24312579, PubMed:23159739). Interacts with AIMP2 (via N-terminus) and MITF (PubMed:9878398, PubMed:14975237, PubMed:15220430, PubMed:23159739, PubMed:26074468). Interacts with TARSL2 (PubMed:24312579).

EXTERNAL LINKS

KARS1

Lysine--tRNA ligase

KARS1

Molecular Synopsis