Directs the termination of nascent peptide synthesis (translation) in response to the termination codons UAA, UAG and UGA. Heterodimer of two subunits, one of which binds GTP. Interacts with TPA1. N5-methylated on Gln-182 by MTQ2. Present with 13100 molecules/cell in log phase SD medium. Belongs to the eukaryotic release factor 1 family.