Journal
BIOMOLECULES
Volume 9, Issue 9, Pages -Publisher
MDPI
DOI: 10.3390/biom9090449
Keywords
26S proteasome; proteasome lid; Rpn11; Cdc53; Cullin; SCF (Skp, Cullin, F-box containing complex); NEDD8 (neural precursor cell expressed developmentally down-regulated 8); Rub1 (Related ubiquitin 1); CSN (COP9 signalosome); Saccharomyces cerevisiae; diauxic shift; budding yeast
Categories
Funding
- Israel Ministry of Science and Technology (MOST)-Italian Ministry of Foreign Affairs (MAE) [3-9022]
- Israel Science Foundation [162/17, 755/19]
- BSF-NSF [2017727]
- Israeli Council for higher education (VATAT)
Ask authors/readers for more resources
The class of Cullin-RING E3 ligases (CRLs) selectively ubiquitinate a large portion of proteins targeted for proteolysis by the 26S proteasome. Before degradation, ubiquitin molecules are removed from their conjugated proteins by deubiquitinating enzymes, a handful of which are associated with the proteasome. The CRL activity is triggered by modification of the Cullin subunit with the ubiquitin-like protein, NEDD8 (also known as Rub1 in Saccharomyces cerevisiae). Cullin modification is then reversed by hydrolytic action of the COP9 signalosome (CSN). As the NEDD8-Rub1 catalytic cycle is not essential for the viability of S. cerevisiae, this organism is a useful model system to study the alteration of Rub1-CRL conjugation patterns. In this study, we describe two distinct mutants of Rpn11, a proteasome-associated deubiquitinating enzyme, both of which exhibit a biochemical phenotype characterized by high accumulation of Rub1-modified Cdc53-Cullin1 (yCul1) upon entry into quiescence in S. cerevisiae. Further characterization revealed proteasome 19S-lid-associated deubiquitination activity that authorizes the hydrolysis of Rub1 from yCul1 by the CSN complex. Thus, our results suggest a negative feedback mechanism via proteasome capacity on upstream ubiquitinating enzymes.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available