Eukaryotic initiation factor 5 (eIF-5) is an important factor in translation initiation. It acts as a GTPase activating factor to mediate the hydrolysis of GTP binding to eIF-2 which is essential for the composition of functional 80S complex. Besides,eIF-5 binds eIF-2 and eIF-3 at the same time, so induces the construction of translation initiation factors complex.