Translational regulator that ensures constant high levels of translation under amino acid starvation. Plays a role as a negative regulator of the gcn2 kinase activity; impairs gcn1-mediated gcn2 activation, and hence gcn2-mediated eIF-2-alpha phosphorylation in amino acid-starved cells and subsequent down-regulation of protein synthesis. In normal conditions, it resides in a actin complex and has no activity. Interacts (via N-terminus) with gcn1 (via C-terminus); this interaction reduces the gcn1-gcn20 complex formation and prevents the interaction of gcn1 with gcn2 protein kinase and gcn2 activation in amino acid-starved cells. Interacts (via C-terminus) with act1; this interaction occurs in a gcn1-independent manner. Interacts with rpl39; this interaction occurs in a gcn1-independent manner. Associates (via middle region) with ribosomes; this association occurs in a gcn1-independent manner and persists under amino acid starvation conditions. Belongs to the IMPACT family.