eRF3a (F9H3X) Rabbit mAb #70152

Eukaryotic release factor 3 (eRF3, GSPT) is an evolutionarily conserved class II release factor and member of the GTPase superfamily that cooperates with eRF1 in polypeptide translation termination (1). Paralogous genes encode a pair of eRF3 proteins (eRF3a/GSPT1, eRF3b/GSPT2) that share a conserved carboxy-terminal GTPase/eRF1-binding domain and a non-conserved amino-terminal PABP1 binding site (2). The eRF3 carboxy-terminal region is involved in translation termination through binding and activation of the eRF1 release factor (1). The amino-terminal region of eRF3 is not required for eRF1 binding and activation, but is implicated in control of mRNA stability (3,4). Expression of eRF3 proteins vary, with eRF3a ubiquitously expressed and proliferation-dependent, while eRF3b expression is more restricted to brain tissue (2,5,6). Research studies demonstrate that eRF3 undergoes caspase-mediated cleavage and degradation related to reduced protein synthesis during DNA damage-induced apoptosis (7). Additional studies indicate that polyglycine expansion of the eRF3a amino terminus is associated with an increased susceptibility to breast and gastric cancer (8,9). It is likely that the polyglycine expansions of amino-terminal eRF3a may affect the ability of eRF3a to undergo caspase-mediated cleavage (9).