DUB-2A is a functional deubiquitinating enzyme.

The upper panel shows the deubiquitination of the ubiquitin-β-galactosidase (Ub-Met-β-gal) fusion protein by various GST-DUB proteins coexpressed in bacteria. A Western blot using anti–β-gal antiserum is shown. Coexpressed plasmids were pBlueScript–DUB-2A(DUB-2A is not expressed) (lane 1); pGEX–DUB-2A(lane 2); pGEX–DUB-2A (C60S) (lane 3); pGEX–DUB-2 (lane 4); pGEX–DUB-2 (C60S) (lane 5); pGEX–DUB-1 (lane 6); and pGEX–DUB-1 (C60S) (lane 7). In the lower panel, GST-DUB fusion proteins were analyzed by an immunoblot with an anti-GST monoclonal antibody (Santa Cruz Biotechnology). E coli extracts were prepared from bacteria transformed with cDNAs encoding no GST fusion protein (empty vector) (lane 1); GST–DUB-2A (lane 2); GST–DUB-2A (C60S) (lane 3); GST–DUB-2 (lane 4); GST–DUB-2 (C60S) (lane 5); GST–DUB-1 (lane 6); and GST–DUB-1 (C60S) (lane 7). The lower band of the doublet in lane 5 is a degradation product of GST–DUB-2(C60S).