EIF5 Antibody (YA4096)(PBS only)

eIF5 (eukaryotic translation initiation factor 5) is a central regulator of eukaryotic translation initiation that functions as a GTPase-activating protein (GAP) for eIF2 and promotes GTP hydrolysis during start-codon recognition^[1][2]. Mechanistically, eIF5 participates in assembly and progression of the translation pre-initiation complex, interacts with multiple initiation factors, and contributes to accurate AUG selection during ribosomal scanning^[2][3]. Beyond its canonical GAP activity, eIF5 also exhibits GDP dissociation inhibitor (GDI) activity toward eIF2, linking GTP hydrolysis to recycling and control of translation initiation complexes^[4]. Therefore, eIF5 occupies a critical position in the molecular pathway that couples start-codon recognition with productive protein synthesis^[2][4]. Experimental studies in yeast and reconstituted eukaryotic translation systems established that eIF5 is required for efficient eIF2 GTPase activation and proper initiation complex function^[1][4]. Structural and biochemical analyses further showed that eIF5 can replace eIF1 on the 40S initiation complex and thereby contribute to stringent start-site selection^[3]. Compared with the related factor eIF5A, which primarily functions during translation elongation and termination rather than initiation, eIF5 acts directly within the translation initiation pathway and regulates eIF2-dependent start-codon selection^[3][4]. Consequently, eIF5 serves as an important experimental target for mechanistic studies of translational control, initiation fidelity, and ribosome-associated regulatory processes^[1][3][4].