OTU domain-containing protein 7B
K48-linked deubiquitinase activity
DJ-1 enhances cell survival through the binding of Cezanne, a negative regulator of NF-kappaB.
Heightened DJ-1 (Park7) expression is associated with a reduction in chemotherapeutic-induced cell death and poor prognosis in several cancers, whereas the loss of DJ-1 function is found in a subgroup of Parkinson disease associated with neuronal death. This study describes a novel pathway by which DJ-1 modulates cell survival. Mass spectrometry shows that DJ-1 interacts with BBS1, CLCF1, MTREF, and Cezanne/OTUD7B/Za20d1. Among these, Cezanne is a known deubiquitination enzyme that inhibits NF-κB activity. DJ-1/Cezanne interaction is confirmed by co-immunoprecipitation of overexpressed and endogenous proteins, maps to the amino-terminal 70 residues of DJ-1, and leads to the inhibition of the deubiquitinating activity of Cezanne. Microarray profiling of shRNA-transduced cells shows that DJ-1 and Cezanne regulate IL-8 and ICAM-1 expression in opposing directions. Similarly, DJ-1 enhances NF-κB nuclear translocation and cell survival, whereas Cezanne reduces these outcomes. Analysis of mouse Park7(-/-) primary cells confirms the regulation of ICAM-1 by DJ-1 and Cezanne. As NF-κB is important in cellular survival and transformation, IL-8 functions as an angiogenic factor and pro-survival signal, and ICAM-1 has been implicated in tumor progression, invasion, and metastasis; these data provide an additional modality by which DJ-1 controls cell survival and possibly tumor progression via interaction with Cezanne.