Telomerase Architecture Revealed (IMAGE) University of California - Berkeley Caption Shown is the space-filling model of human telomerase holoenzyme structure determined by cryo-electron microscopy (cryo-EM). Telomerase catalyzes the synthesis of telomeric DNA (green) at the ends of chromosomes (blue) to compensate for the loss of telomeres during genome replication. The structure comprises two lobes with distinct functionalities: the catalytic core (purple) responsible for DNA synthesis and an H/ACA ribonucleoprotein lobe (cyan, teal and light green) important for telomerase biogenesis and localization to the Cajal body (red dots and lower left in closeup). Given that telomerase regulation is implicated in cancer and aging, this first architectural visualization of human telomerase represents an important breakthrough in the telomerase field and telomerase-based therapeutic design. Credit Janet Iwasa Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.