KARS1 is an essential host factor packaged into HIV-1 virions for reverse transcription from co-packaged human tRNALys357 and EPRS1 binds TGEV GAIT-like RNA motif; EPRS1 and SPEAR interaction was pursued since a direct, virus RNA-facing role of EPRS1 in any human virus infection has not been reported. The gene discussed is EPRS1; the disease is viral infectious disease.