To ubiquitinate or to deubiquitinate: it all depends on the partners.
Ub (ubiquitin) and Ubls (Ub-like molecules) are peptide modifiers that change the fate and function of their substrates. A plethora of enzyme activities and protein cofactors are required for either the conjugation (mainly E3 ligases) or deconjugation of Ub and Ubls. Most of the data have been gathered on describing individual enzymes and their partners, but an increasing number of reports point to the formation of multisubunit complexes regulated by cross-talk between Ub and Ubl systems and which contain opposing conjugation/deconjugation activities. This minireview focuses on these latest reports and proposes that these complexes, which are able to recruit transient partners, shift cofactors and integrate different signalling stimuli, are a common strategy to regulate highly dynamic processes, in a switch-on/switch-off type of mechanism, thus responding promptly to cellular requirements.
Marfany
Gemma
G
Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Avda. Diagonal 645, 08028 Barcelona, Spain. gmarfany@ub.edu
Denuc
Amanda
A
D010450:Endopeptidases / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism; D006801:Humans; D046912:Multiprotein Complexes / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D021122:Protein Subunits / Q000378:metabolism; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D008941:Spindle Apparatus / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism
D046912:Multiprotein Complexes; D028861:Nuclear Pore Complex Proteins; D021122:Protein Subunits; D025841:Small Ubiquitin-Related Modifier Proteins; D025801:Ubiquitin; D044767:Ubiquitin-Protein Ligases; D010450:Endopeptidases