Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2003 Jan;42(4):199-208.
doi: 10.1007/s00294-002-0350-7. Epub 2002 Dec 13.

Investigating the Importance of Proteasome-Interaction for Rad23 Function


Investigating the Importance of Proteasome-Interaction for Rad23 Function

David Lambertson et al. Curr Genet. .


Rad23 contributes to diverse cellular functions that include DNA repair, stress response and growth control. An amino-terminal ubiquitin-like (UbL) domain in Rad23 interacts with catalytically active proteasomes and internal sequences bind multi-ubiquitinated proteins. Rad23 regulates the assembly of substrate-linked multi-ubiquitin chains, promotes efficient degradation of model substrates, and plays an overlapping role with the proteasome subunit, Rpn10. These and other results led to the hypothesis that Rad23 translocates proteolytic substrates to the proteasome to promote degradation. It was previously shown that the UbL domain in Rad23 could be functionally replaced by ubiquitin. However, monomeric ubiquitin does not bind the proteasome efficiently, and we therefore investigated whether proteasome interaction was required for all Rad23 functions. We report here that the ubiquitin moiety in Ub-rad23 is ubiquitinated in vivo and could provide an alternate mechanism for binding the proteasome. These results suggest that the localization of Rad23 to the proteasome, either by its UbL domain, or following ubiquitination of an amino-terminal ubiquitin moiety (Ub-rad23), is necessary for full activity.

Similar articles

See all similar articles

Cited by 10 articles

See all "Cited by" articles


    1. Nat Struct Biol. 1998 Dec;5(12):1042-7 - PubMed
    1. Biochemistry. 2000 Nov 21;39(46):14103-12 - PubMed
    1. Mutat Res. 2000 Jun 30;451(1-2):13-24 - PubMed
    1. Mol Cell Biol. 2002 Jul;22(13):4902-13 - PubMed
    1. Nucleic Acids Res. 2002 Jan 15;30(2):581-91 - PubMed

Publication types

MeSH terms

LinkOut - more resources