Structure of mammalian initiation factor 3 (eIF3)
Structure of mammalian initiation factor 3 (eIF3) seen by electronic cryo-microscopy (left) and interpreted by an atomic model (right). Proteins are translated from the messenger RNA by ribosome. The process is started by a crucial stage called initiation. In mammals, this stage puts more than a dozen initiation factors (eIFs) into play. Initiation factor 3 (eIF3) is comprised of 13 sub-units, 5 of which are peripheral and 8 of which are within a preserved central core, shown here. Researchers have succeeded in establishing, to a resolution of 0.6 nanometres, the three-dimensional structure of the initiation complex of mammalian protein translation. Understanding the sophisticated architecture of this complex and its interaction with key initiation factor eIF3 opens new perspectives in the search for therapeutic antiviral and anti-parasite agents.