Eukaryotic translation initiation factor 5A-2

Function

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).

Post-translational modifications

Lys-50 undergoes hypusination, a unique post-translational modification that consists in the addition of a butylamino group from spermidine to lysine side chain and leads to the formation of a hypusine residue. eIF-5As are the only known proteins to undergo this modification, which is essential for their function.

Sequence Similarities

Belongs to the eIF-5A family.

Tissue Specificity

Expressed in ovarian and colorectal cancer cell lines (at protein level). Highly expressed in testis. Overexpressed in some cancer cells.

Cellular localization

• Cytoplasm
• Nucleus
• Endoplasmic reticulum membrane
• Peripheral membrane protein
• Cytoplasmic side
• Hypusine modification promotes the nuclear export and cytoplasmic localization and there was a dynamic shift in the localization from predominantly cytoplasmic to primarily nuclear under apoptotic inducing conditions.

Alternative names

Eukaryotic translation initiation factor 5A-2, eIF-5A-2, eIF-5A2, Eukaryotic initiation factor 5A isoform 2, EIF5A2

Database links

swissprot:Q9GZV4 entrezGene:1984 omim:600187 omim:605782 swissprot:P63241 entrezGene:56648