Involvement of a eukaryotic-like ubiquitin-related modifier in the proteasome pathway of the archaeon Sulfolobus acidocaldarius.
Anjum, R.S., Bray, S.M., Blackwood, J.K., Kilkenny, M.L., Coelho, M.A., Foster, B.M., Li, S., Howard, J.A., Pellegrini, L., Albers, S.V., Deery, M.J., Robinson, N.P.(2015) Nat Commun 6: 8163-8163
- PubMed: 26348592
- DOI: https://doi.org/10.1038/ncomms9163
- Primary Citation of Related Structures:
4WWM - PubMed Abstract:
In eukaryotes, the covalent attachment of ubiquitin chains directs substrates to the proteasome for degradation. Recently, ubiquitin-like modifications have also been described in the archaeal domain of life. It has subsequently been hypothesized that ubiquitin-like proteasomal degradation might also operate in these microbes, since all archaeal species utilize homologues of the eukaryotic proteasome. Here we perform a structural and biochemical analysis of a ubiquitin-like modification pathway in the archaeon Sulfolobus acidocaldarius. We reveal that this modifier is homologous to the eukaryotic ubiquitin-related modifier Urm1, considered to be a close evolutionary relative of the progenitor of all ubiquitin-like proteins. Furthermore we demonstrate that urmylated substrates are recognized and processed by the archaeal proteasome, by virtue of a direct interaction with the modifier. Thus, the regulation of protein stability by Urm1 and the proteasome in archaea is likely representative of an ancient pathway from which eukaryotic ubiquitin-mediated proteolysis has evolved.
Organizational Affiliation:
Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1GA, UK.