Figure 1.

Schematic illustration of the domain organization of human USP15. Catalytic core (shown in cyan) is located in the carboxyl-terminal portion of USP15. The catalytic core of USP15 contains an inserted UBL domain. The USP15 with its active triad C269, H862, and D879 are denoted by thick red lines, and the Zn-coordinating Cys residues in positions 419, 422, 780, and 783 are highlighted by thick black lines. Four residues (Met-122, Phe-123, Val-124, and His-126) interacting with SART3 located between the amino-terminal DUSP domain and UBL domain are indicated. DUSP, domain present in ubiquitin-specific proteases; UBL, ubiquitin-like fold.