Translation factor that promotes translation elongation and termination, particularly upon ribosome stalling at specific amino acid sequence contexts (PubMed:14622290). Binds between the exit (E) and peptidyl (P) site of the ribosome and promotes rescue of stalled ribosome: specifically required for efficient translation of polyproline-containing peptides as well as other motifs that stall the ribosome. Acts as a ribosome quality control (RQC) cofactor by joining the RQC complex to facilitate peptidyl transfer during CAT tailing step (By similarity). Also involved in actin dynamics and cell cycle progression, mRNA decay and probably in a pathway involved in stress response and maintenance of cell wall integrity (By similarity). {ECO:0000250|UniProtKB:P23301, ECO:0000250|UniProtKB:P63241, ECO:0000269|PubMed:14622290}. This is the function of EIF5A2 (eukaryotic translation initiation factor 5A2, ENSG00000163577).