Letter abstract
Nature Cell Biology 6, 634 - 641 (2004)
Published online: 20 June 2004 | doi:10.1038/ncb1143
Proteolysis-independent regulation of the transcription factor Met4 by a single Lys 48-linked ubiquitin chain
Karin Flick1, Ikram Ouni1, James A. Wohlschlegel2, Chrissy Capati1, W. Hayes McDonald2,3, John R. Yates, 3rd2 & Peter Kaiser1
The ubiquitin ligase SCFMet30 is required for cell cycle progression in budding yeast. The critical function of SCFMet30 is inactivation of the transcriptional activator Met4. Here we show that a single ubiquitin chain is attached to Met4 through lysine at position 163. Inhibition of Met4 ubiquitination by mutating lysine to arginine at this position constitutively activates, but does not stabilize, Met4. This supports a proteolysis-independent role of Cdc34–SCFMet30-catalysed Met4 ubiquitination. Surprisingly, the ubiquitin chain attached to Met4 is linked through Lys 48 in ubiquitin, a ubiquitin chain structure that is usually required for substrate targeting to the 26S proteasome. These results suggest that Lys 48-linked ubiquitin chains can have a regulatory role independent of proteolysis.
- Department of Biological Chemistry, University of California Irvine, Irvine, CA 92697, USA.
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
- Current address: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Correspondence to: Peter Kaiser1 e-mail: pkaiser@uci.edu
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
NEWS AND VIEWS
Ubiquitin signalling: what's in a chain?Nature Cell Biology News and Views (01 Jul 2004)
Cdc34: cycling on and off the SCFNature Cell Biology News and Views (01 Oct 2003)
See all 3 matches for News And ViewsRESEARCH
A ubiquitin-interacting motif protects polyubiquitinated Met4 from degradation by the 26S proteasomeNature Cell Biology Letter (01 May 2006)
Quantitative analysis of in vitro ubiquitinated cyclin B1 reveals complex chain topologyNature Cell Biology Article (01 Jul 2006)
See all 34 matches for Research
