Ubiquitin-specific protease USP4 regulates several cellular signalling pathways. Here, Clerici et al.show that the DUSP–Ubl domain of USP4 is required for full catalytic activity, by enhancing the release of ubiquitin from the catalytic site after substrate hydrolysis.
- Marcello Clerici
- Mark P. A. Luna-Vargas
- Titia K. Sixma