Structural insights into Cullin4-RING ubiquitin ligase remodelling by Vpr from simian immunodeficiency viruses
Fig 2
Crystal structure of the DDB1/DCAF1-CtD/Vprmus complex.
(A) Overall structure of the DDB1/DCAF1-CtD/Vprmus complex in two views. DCAF1-CtD is shown as grey cartoon and semi-transparent surface. Vprmus is shown as a dark green cartoon with the co-ordinated zinc ion shown as grey sphere. T4L and DDB1 have been omitted for clarity. (B) Superposition of apo-DCAF1-CtD (light blue cartoon) with Vprmus-bound DCAF1-CtD (grey/green cartoon). Only DCAF1-CtD regions with significant structural differences between apo- and Vprmus-bound forms are shown. Disordered loops are indicated as dashed lines. (C) Comparison of the binary Vprmus/DCAF1-CtD and ternary Vpxsm/DCAF1-CtD/SAMHD1-CtD complexes. For DCAF1-CtD, only the N-terminal “acidic loop” region is shown. Vprmus, DCAF1-CtD and bound zinc are coloured as in A; Vpxsm is represented as orange cartoon and SAMHD1-CtD as pink cartoon. Selected Vpr/Vpx/DCAF1-CtD side chains are shown as sticks, and electrostatic interactions between these side chains are indicated as dotted lines. (D) GF analysis of in vitro reconstitution of protein complexes containing DDB1/DCAF1-CtD/Vprmus or the Vprmus R15E/R75E mutant, and SAMHD1. SDS-PAGE analyses of corresponding GF fractions are shown below the chromatogram, with boxes colour-coded with respect to the chromatogram. (E-F) In vitro reconstitution of protein complexes containing SAMHD1 and Vprmus R15E/R75E (E) or DDB1/DCAF1-CtD and Vprmus R15E/R75E (F). SDS-PAGE analyses of corresponding GF fractions are shown below the chromatogram, with boxes colour-coded with respect to the chromatogram. The asterisk and double asterisk indicate slight contaminations with remaining GST-3C protease and the GST purification tag, respectively.