Glutamine--tRNA ligase. Plays a critical role in brain development. ATP + L-glutamine + tRNA(Gln) = AMP + diphosphate + L-glutaminyl-tRNA(Gln) Monomer. Part of 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. Interacts with RARS1. Part of a complex composed of RARS1, QARS1 and AIMP1. Detected in dorsal root ganglia (at protein level). Detected in dorsal root ganglia. Down-regulated after peripheral nerve injury. Belongs to the class-I aminoacyl-tRNA synthetase family.