<i>In vitro</i> self-ubiquitination assay of GpDSR7.

<p>The C-terminal TM domain truncated form of GpDSR7 was defined as GpDSR7^Δ. (A) GST-tagged GpDSR7^Δ fusion protein was assayed for E3 ubiquitin ligase activity in the presence of E1, E2, and Ubi-Myc. Ubiquitinated proteins were detected by western blot analysis using an anti-GST antibody (left panel) and anti-Myc antibody (right panel). Triangles indicate non-ubiquitinated GST-GpDSR7^Δ. (B) Purified WT GST-GpDSR7^Δ and mutant proteins were used in the E3 Ub ligase enzyme assay.