Cotranslational quality control factor involved in the No-Go Decay (NGD) pathway (By similarity). In the presence of pix and pelo, is required for 48S complex formation from 80S ribosomes and dissociation of vacant 80S ribosomes (By similarity). Together with pelo and in presence of pix, 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 (By similarity). Together with pelo, required for transposon silencing in the ovary and testis (PubMed:26124316). Together with pelo, promotes meiosis and spermatid individualization during spermatogenesis (PubMed:30824860). Interacts with pelo. Expressed in ovaries (at protein level). In germlines, increases transposable elements transcription at both mRNA and protein levels (PubMed:26124316). Results in male sterility: male testes are morphologically normal but no mature sperm is formed (PubMed:30824860). Results in defective meiosis and spermatid individualization during spermatogenesis (PubMed:30824860). Belongs to the TRAFAC class translation factor GTPase superfamily. Classic translation factor GTPase family.