Glutathione S-transferase C-terminal-like, alpha helical domain of Aminoacyl tRNA synthetase complex-Interacting Multifunctional Protein 2
Glutathione S-transferase (GST) C-terminal domain family, Aminoacyl tRNA synthetase complex-Interacting Multifunctional Protein (AIMP) 2 subfamily; AIMPs are non-enzymatic cofactors that play critical roles in the assembly and formation of a macromolecular multi-tRNA synthetase protein complex that functions as a molecular hub to coordinate protein synthesis. There are three AIMPs, named AIMP1-3, which play diverse regulatory roles. AIMP2, also called p38 or JTV-1, contains a C-terminal domain with similarity to the C-terminal alpha helical domain of GSTs. It plays an important role in the control of cell fate via antiproliferative (by enhancing the TGF-beta signal) and proapoptotic (activation of p53 and TNF-alpha) activities. Its roles in the control of cell proliferation and death suggest that it is a potent tumor suppressor. AIMP2 heterozygous mice with lower than normal expression of AIMP2 show high susceptibility to tumorigenesis. AIMP2 is also a substrate of Parkin, an E3 ubiquitin ligase that is involved in the ubiquitylation and proteasomal degradation of its substrates. Mutations in the Parkin gene is found in 50% of patients with autosomal-recessive early-onset parkinsonism. The accumulation of AIMP2, due to impaired Parkin function, may play a role in the pathogenesis of Parkinson's disease.