Required for assembly and stability of the aminoacyl-tRNA synthase complex (PubMed:19131329). Mediates ubiquitination and degradation of FUBP1, a transcriptional activator of MYC, leading to MYC down-regulation which is required for aveolar type II cell differentiation. Blocks MDM2-mediated ubiquitination and degradation of p53/TP53. Functions as a proapoptotic factor. Part of the multisynthetase complex (MSC), a multisubunit complex that groups tRNA ligases for Arg (RARS1), Asp (DARS1), Gln (QARS1), Ile (IARS1), Leu (LARS1), Lys (KARS1), Met (MARS1) the bifunctional ligase for Glu and Pro (EPRS1) and the auxiliary subunits AIMP1/p43, AIMP2/p38 and EEF1E1/p18 (PubMed:24312579, PubMed:19131329, PubMed:19289464). Interacts (via N-terminus) with KARS1 (PubMed:9878398, PubMed:15220430, PubMed:18029264, PubMed:23159739, PubMed:26074468). Interacts with EPRS1 (PubMed:26472928). Forms a linear complex that contains MARS1, EEF1E1, EPRS1 and AIMP2 that is at the core of the multisubunit complex (PubMed:26472928). Binds FUBP1 (via C-terminus). Interacts in both its unphosphorylated and phosphorylated forms with p53/TP53 (via N-terminus) in the nucleus following UV irradiation. Interacts (via N-terminus) with PRKN/parkin (via first RING-type domain) (PubMed:16135753). Interacts with TARS3 (PubMed:24312579). Following DNA damage, dissociates from the aminoacyl-tRNA synthase complex and translocates from the cytoplasm to the nucleus. Phosphorylated on serine residues in response to UV irradiation. Ubiquitinated by PRKN, leading to its degradation by the proteasome. Mutant PRKN fails to ubiquitinate AIMP2 efficiently, allowing its accumulation which may contribute to neurodegeneration associated with Parkinson disease. The disease may be caused by variants affecting the gene represented in this entry. Accumulates in brains affected by autosomal-recessive juvenile parkinsonism, idiopathic Parkinson disease and diffuse Lewy body disease.