Cotranslational quality control factor involved in the No-Go Decay (NGD) pathway. In the presence of ABCE1 and PELO, is required for 48S complex formation from 80S ribosomes and dissociation of vacant 80S ribosomes. Together with PELO and in presence of ABCE1, recognizes stalled ribosomes and promotes dissociation of elongation complexes assembled on non-stop mRNAs; this triggers endonucleolytic cleavage of the mRNA, a mechanism to release non-functional ribosomes and to degrade damaged mRNAs as part of the No-Go Decay (NGD) pathway. Interacts with the SKI complex. Belongs to the TRAFAC class translation factor GTPase superfamily. Classic translation factor GTPase family.