The RNA exosome is a multisubunit 3′ to 5′ exoribonuclease complex that participates in degradation and processing of cellular RNA. To determine the activities and structure of the eukaryotic exosome, we report the reconstitution of 9-subunit exosomes from yeast and human and reconstitution of 10- and 11-subunit exosomes from yeast. Comparative biochemical analysis between purified subunits and reconstituted exosomes using AU-rich, polyadenylated (poly[A]), generic, and structured RNA substrates reveals processive phosphorolytic activities for human Rrp41/Rrp45 and the 9-subunit human exosome, processive hydrolytic activities for yeast Rrp44 and the yeast 10-subunit exosome, distributive hydrolytic activities for Rrp6, and processive and distributive hydrolytic activities for the yeast 11-subunit exosome. To elucidate the architecture of a eukaryotic exosome, its conserved surfaces, and the structural basis for RNA decay, we report the X-ray structure determination for the 286 kDa nine-subunit human exosome at 3.35 Å. © 2006 Elsevier Inc. All rights reserved.
Liu, Q., Greimann, J. C., & Lima, C. D. (2006). Reconstitution, Activities, and Structure of the Eukaryotic RNA Exosome. Cell, 127(6), 1223–1237. https://doi.org/10.1016/j.cell.2006.10.037