Product of an upstream open reading frame (ORF) of PRKCH which regulates translation of the downstream protein kinase C eta (PKC-eta) ORF (PubMed:19797084, PubMed:34593629). Functions as a repressive element that maintains low basal levels of PKC-eta in growing cells but enhances its expression during stress conditions induced by amino acid starvation in a EIF2AK4/GCN2-dependent manner (PubMed:19797084, PubMed:34593629). In addition to its role in regulating PKC-eta translation, also inhibits the kinase activity of PKC-eta as well as other protein kinases including PRKCD, PRKCQ and PRKCE but not PRKCA, PRKCG or PRKCZ (PubMed:34593629).
