Within the isolated lid sub-complex of the proteasome, a finely tuned network of interactions maintains the deubiquitinase in an inhibited conformation; dramatic rearrangements of the lid subunits upon incorporation into the holoenzyme lead to the deubiquitinase’s activation.
Obligate intracellular Chlamydia secrete a deubiquitinating enzyme (Cdu1) into the membrane of the Chlamydia-containing vacuole to deubiquitinate selected host proteins and support the survival of the bacteria during genital infection.
A deubiquitinase antagonizes the activity of an associated E3 ligase to prevent uncontrolled ubiquitination of a degradation machinery protein and thus maintain its functionality in protein quality control at the endoplasmic reticulum.
A signaling pathway—comprising a linear sequence of the ubiquitin-selective chaperone Cdc48/p97 and the deubiquitylases Ubp12 and Ubp2—synergistically regulates mitochondrial fusion, thereby fine-tuning ubiquitylation of the mitofusin Fzo1.
Expression of plant immune genes is controlled by the opposing actions of ubiquitin ligases and deubiquitinases that modify the master coactivator NPR1, thereby regulating its intrinsic transcriptional activity.