Pro-inflammatory Function of Secreted Threonyl-tRNA synthetase

Abstract

ARS is an enzyme that pairs tRNA with each amino acid of its own. Among the 20 different amino acids eukaryotes carry, threonyl-tRNA synthetase (TRS) delivers Threonine to tRNA to regulate protein synthesis. However, there is not much of a study done on functions of TRS other than conventional features. It is currently known that TRS is secreted by the external stimulus such as VEGF and TNF. This mechanism causes metastasis and angiogenesis of tumor, but it is not well studied how secreted TRS functions in this circumstances. Inflammatory cytokines are activated by extracellular signaling and then activated cytokines are secreted through the cell membrane. I expected secreted TRS can do a role of inflammatory function. So, I expressed and purified recombinant human TRS in E. coli. Responses of TRS were studied with the purified TRS on various cell lines. Consequently, I found that recombinant TRS can stimulate important cytokines and chemokines such as IL-6 and IL-8, respectively. On this result, for confirming cytokine activities of TRS, TRS plays an important role in inducing the inflammatory immune response. The present study suggested that TRS can be developed as a novel biomarker targeting newly discovered immune responses and inflammatory diseases.