Key regulators of translation. The main effectors of the translational machinery are the ribosome (in grey) and the canonical trans-regulators (in brown) regulating the initiation, elongation and termination of translation. Additional trans-regulators of translation (in green), including RNA binding proteins (RBPs), internal ribosome entry site (IRES)-trans acting factors (ITAFs), miRNAs and lncRNAs, act in concert with the canonical trans-regulators to modulate the translational efficiency of subsets of mRNAs. These trans-regulators interact with cis-elements of the targeted mRNA, called cis-regulators (in blue), including binding sites for RBP such as cytoplasmic polyadenylation elements (CPEs) and AU-rich elements (AREs), IRES, stem-loops and G-quadruplex. In addition, several cis-regulators, including upstream open reading frames (uORFs), 5′-terminal oligopyrimidine tract (5′TOP), translation inhibitory element (TIE), pyrimidine-rich translational element (PRTE), and cytosine-enriched regulator of translation (CERT) modulate the translational efficiency of subsets of mRNAs during the initiation step. (adapted from Marcel, Oncogene, 2015, [6]).