Translation initiation factor (eIF (for eukaryotic initiation factor), IF (for prokaryotic initiation factor))

Translation initiation factors are a broad class of proteins essential for the initiation phase of mRNA translation, a central step in protein biosynthesis in both prokaryotes and eukaryotes[5][1]. They facilitate ribosome assembly on mRNA, position initiator tRNA, and regulate the efficiency and accuracy of start codon recognition[4][8]. In eukaryotes, these include multiple complexes such as eIF2 (brings the initiator tRNA), eIF3 (scaffold/regulator), and eIF4 (cap recognition and mRNA recruitment), while bacteria have IF1, IF2, and IF3[5][1]. The activities of these factors are regulated by signaling pathways such as PI3K/AKT/mTOR, especially in cancer cells, where dysregulation of eIFs is linked to increased protein synthesis and tumor progression[9][2]. Therapeutic strategies increasingly seek to inhibit overactive translation initiation as a means to suppress oncogenic protein expression, but because these factors are fundamentally required for all cellular protein synthesis, therapeutic targeting faces risks of toxicity[9].

Other names

eukaryotic initiation factorIF (bacterial initiation factor)eIF (eukaryotic initiation factor)translation initiation protein

Inhibition of translation initiation, Disruption of mRNA recruitment or ribosome assembly, Modulation of cap-dependent translation