Sensitivity to antitubulin chemotherapeutics is regulated by MCL1 and FBW7.

Microtubules have pivotal roles in fundamental cellular processes and are targets of antitubulin chemotherapeutics. Microtubule-targeted agents such as Taxol and vincristine are prescribed widely for various malignancies, including ovarian and breast adenocarcinomas, non-small-cell lung cancer, leukaemias and lymphomas. These agents arrest cells in mitosis and subsequently induce cell death through poorly defined mechanisms.

Ubiquitin hydrolase Dub3 promotes oncogenic transformation by stabilizing Cdc25A.

The dual specificity (Tyr/Thr) phosphatase Cdc25A activates cyclin-dependent kinases (Cdks) to promote cell-cycle progression and has significant oncogenic potential. Cdc25A protein levels are regulated tightly in normal tissues, but many human cancers overexpress Cdc25A. The underlying mechanism for overexpression has been enigmatic.

DUBA: a deubiquitinase that regulates type I interferon production.

Production of type I interferon (IFN-I) is a critical host defense triggered by pattern-recognition receptors (PRRs) of the innate immune system. Deubiquitinating enzyme A (DUBA), an ovarian tumor domain-containing deubiquitinating enzyme, was discovered in a small interfering RNA-based screen as a regulator of IFN-I production. Reduction of DUBA augmented the PRR-induced IFN-I response, whereas ectopic expression of DUBA had the converse effect.

De-ubiquitination and ubiquitin ligase domains of A20 downregulate NF-kappaB signalling.

NF-kappaB transcription factors mediate the effects of pro-inflammatory cytokines such as tumour necrosis factor-alpha and interleukin-1beta. Failure to downregulate NF-kappaB transcriptional activity results in chronic inflammation and cell death, as observed in A20-deficient mice. A20 is a potent inhibitor of NF-kappaB signalling, but its mechanism of action is unknown.

Human De-etiolated-1 regulates c-Jun by assembling a CUL4A ubiquitin ligase.

Arabidopsis thaliana De-etiolated-1 (AtDET1) is a highly conserved protein, with orthologs in vertebrate and invertebrate organisms. AtDET1 negatively regulates photomorphogenesis, but its biochemical mechanism and function in other species are unknown. We report that human DET1 (hDET1) promotes ubiquitination and degradation of the proto-oncogenic transcription factor c-Jun by assembling a multisubunit ubiquitin ligase containing DNA Damage Binding Protein-1 (DDB1), cullin 4A (CUL4A), Regulator of Cullins-1 (ROC1), and constitutively photomorphogenic-1.