Cytosolic seryl-tRNA synthetase; class II aminoacyl-tRNA synthetase that aminoacylates tRNA(Ser), displays tRNA-dependent amino acid recognition which enhances discrimination of the serine substrate; copurifies with Abp140p in an RNA-dependent manner and stimulates 3-methylcytidine (m3C) modification of residue 32 of the tRNA anticodon loop of tRNA-Ser; interacts with peroxin Pex21p